package org.apache.lucene.index;
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.Closeable;
import java.io.IOException;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.FieldInfos.FieldNumberBiMap;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.index.PayloadProcessorProvider.DirPayloadProcessor;
import org.apache.lucene.index.SegmentCodecs.SegmentCodecsBuilder;
import org.apache.lucene.index.codecs.CodecProvider;
import org.apache.lucene.search.Query;
import org.apache.lucene.store.AlreadyClosedException;
import org.apache.lucene.store.BufferedIndexInput;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.Lock;
import org.apache.lucene.store.LockObtainFailedException;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.Constants;
import org.apache.lucene.util.ThreadInterruptedException;
import org.apache.lucene.util.MapBackedSet;
/**
An <code>IndexWriter</code> creates and maintains an index.
<p>The <code>create</code> argument to the {@link
#IndexWriter(Directory, IndexWriterConfig) constructor} determines
whether a new index is created, or whether an existing index is
opened. Note that you can open an index with <code>create=true</code>
even while readers are using the index. The old readers will
continue to search the "point in time" snapshot they had opened,
and won't see the newly created index until they re-open. There are
also {@link #IndexWriter(Directory, IndexWriterConfig) constructors}
with no <code>create</code> argument which will create a new index
if there is not already an index at the provided path and otherwise
open the existing index.</p>
<p>In either case, documents are added with {@link #addDocument(Document)
addDocument} and removed with {@link #deleteDocuments(Term)} or {@link
#deleteDocuments(Query)}. A document can be updated with {@link
#updateDocument(Term, Document) updateDocument} (which just deletes
and then adds the entire document). When finished adding, deleting
and updating documents, {@link #close() close} should be called.</p>
<a name="flush"></a>
<p>These changes are buffered in memory and periodically
flushed to the {@link Directory} (during the above method
calls). A flush is triggered when there are enough
buffered deletes (see {@link IndexWriterConfig#setMaxBufferedDeleteTerms})
or enough added documents since the last flush, whichever
is sooner. For the added documents, flushing is triggered
either by RAM usage of the documents (see {@link
IndexWriterConfig#setRAMBufferSizeMB}) or the number of added documents.
The default is to flush when RAM usage hits 16 MB. For
best indexing speed you should flush by RAM usage with a
large RAM buffer. Note that flushing just moves the
internal buffered state in IndexWriter into the index, but
these changes are not visible to IndexReader until either
{@link #commit()} or {@link #close} is called. A flush may
also trigger one or more segment merges which by default
run with a background thread so as not to block the
addDocument calls (see <a href="#mergePolicy">below</a>
for changing the {@link MergeScheduler}).</p>
<p>If an index will not have more documents added for a while and optimal search
performance is desired, then either the full {@link #optimize() optimize}
method or partial {@link #optimize(int)} method should be
called before the index is closed.</p>
<p>Opening an <code>IndexWriter</code> creates a lock file for the directory in use. Trying to open
another <code>IndexWriter</code> on the same directory will lead to a
{@link LockObtainFailedException}. The {@link LockObtainFailedException}
is also thrown if an IndexReader on the same directory is used to delete documents
from the index.</p>
<a name="deletionPolicy"></a>
<p>Expert: <code>IndexWriter</code> allows an optional
{@link IndexDeletionPolicy} implementation to be
specified. You can use this to control when prior commits
are deleted from the index. The default policy is {@link
KeepOnlyLastCommitDeletionPolicy} which removes all prior
commits as soon as a new commit is done (this matches
behavior before 2.2). Creating your own policy can allow
you to explicitly keep previous "point in time" commits
alive in the index for some time, to allow readers to
refresh to the new commit without having the old commit
deleted out from under them. This is necessary on
filesystems like NFS that do not support "delete on last
close" semantics, which Lucene's "point in time" search
normally relies on. </p>
<a name="mergePolicy"></a> <p>Expert:
<code>IndexWriter</code> allows you to separately change
the {@link MergePolicy} and the {@link MergeScheduler}.
The {@link MergePolicy} is invoked whenever there are
changes to the segments in the index. Its role is to
select which merges to do, if any, and return a {@link
MergePolicy.MergeSpecification} describing the merges. It
also selects merges to do for optimize(). (The default is
{@link LogByteSizeMergePolicy}. Then, the {@link
MergeScheduler} is invoked with the requested merges and
it decides when and how to run the merges. The default is
{@link ConcurrentMergeScheduler}. </p>
<a name="OOME"></a><p><b>NOTE</b>: if you hit an
OutOfMemoryError then IndexWriter will quietly record this
fact and block all future segment commits. This is a
defensive measure in case any internal state (buffered
documents and deletions) were corrupted. Any subsequent
calls to {@link #commit()} will throw an
IllegalStateException. The only course of action is to
call {@link #close()}, which internally will call {@link
#rollback()}, to undo any changes to the index since the
last commit. You can also just call {@link #rollback()}
directly.</p>
<a name="thread-safety"></a><p><b>NOTE</b>: {@link
IndexWriter} instances are completely thread
safe, meaning multiple threads can call any of its
methods, concurrently. If your application requires
external synchronization, you should <b>not</b>
synchronize on the <code>IndexWriter</code> instance as
this may cause deadlock; use your own (non-Lucene) objects
instead. </p>
<p><b>NOTE</b>: If you call
<code>Thread.interrupt()</code> on a thread that's within
IndexWriter, IndexWriter will try to catch this (eg, if
it's in a wait() or Thread.sleep()), and will then throw
the unchecked exception {@link ThreadInterruptedException}
and <b>clear</b> the interrupt status on the thread.</p>
*/
/*
* Clarification: Check Points (and commits)
* IndexWriter writes new index files to the directory without writing a new segments_N
* file which references these new files. It also means that the state of
* the in memory SegmentInfos object is different than the most recent
* segments_N file written to the directory.
*
* Each time the SegmentInfos is changed, and matches the (possibly
* modified) directory files, we have a new "check point".
* If the modified/new SegmentInfos is written to disk - as a new
* (generation of) segments_N file - this check point is also an
* IndexCommit.
*
* A new checkpoint always replaces the previous checkpoint and
* becomes the new "front" of the index. This allows the IndexFileDeleter
* to delete files that are referenced only by stale checkpoints.
* (files that were created since the last commit, but are no longer
* referenced by the "front" of the index). For this, IndexFileDeleter
* keeps track of the last non commit checkpoint.
*/
public class IndexWriter implements Closeable {
/**
* Name of the write lock in the index.
*/
public static final String WRITE_LOCK_NAME = "write.lock";
/**
* Absolute hard maximum length for a term, in bytes once
* encoded as UTF8. If a term arrives from the analyzer
* longer than this length, it is skipped and a message is
* printed to infoStream, if set (see {@link
* #setInfoStream}).
*/
public final static int MAX_TERM_LENGTH = DocumentsWriter.MAX_TERM_LENGTH_UTF8;
// The normal read buffer size defaults to 1024, but
// increasing this during merging seems to yield
// performance gains. However we don't want to increase
// it too much because there are quite a few
// BufferedIndexInputs created during merging. See
// LUCENE-888 for details.
private final static int MERGE_READ_BUFFER_SIZE = 4096;
// Used for printing messages
private static final AtomicInteger MESSAGE_ID = new AtomicInteger();
private int messageID = MESSAGE_ID.getAndIncrement();
volatile private boolean hitOOM;
private final Directory directory; // where this index resides
private final Analyzer analyzer; // how to analyze text
private volatile long changeCount; // increments every time a change is completed
private long lastCommitChangeCount; // last changeCount that was committed
private SegmentInfos rollbackSegmentInfos; // segmentInfos we will fallback to if the commit fails
volatile SegmentInfos pendingCommit; // set when a commit is pending (after prepareCommit() & before commit())
volatile long pendingCommitChangeCount;
final SegmentInfos segmentInfos; // the segments
final FieldNumberBiMap globalFieldNumberMap;
private DocumentsWriter docWriter;
private IndexFileDeleter deleter;
private Set<SegmentInfo> segmentsToOptimize = new HashSet<SegmentInfo>(); // used by optimize to note those needing optimization
private int optimizeMaxNumSegments;
private Lock writeLock;
private boolean closed;
private boolean closing;
// Holds all SegmentInfo instances currently involved in
// merges
private HashSet<SegmentInfo> mergingSegments = new HashSet<SegmentInfo>();
private MergePolicy mergePolicy;
private final MergeScheduler mergeScheduler;
private LinkedList<MergePolicy.OneMerge> pendingMerges = new LinkedList<MergePolicy.OneMerge>();
private Set<MergePolicy.OneMerge> runningMerges = new HashSet<MergePolicy.OneMerge>();
private List<MergePolicy.OneMerge> mergeExceptions = new ArrayList<MergePolicy.OneMerge>();
private long mergeGen;
private boolean stopMerges;
private final AtomicInteger flushCount = new AtomicInteger();
private final AtomicInteger flushDeletesCount = new AtomicInteger();
final ReaderPool readerPool = new ReaderPool();
final BufferedDeletesStream bufferedDeletesStream;
// This is a "write once" variable (like the organic dye
// on a DVD-R that may or may not be heated by a laser and
// then cooled to permanently record the event): it's
// false, until getReader() is called for the first time,
// at which point it's switched to true and never changes
// back to false. Once this is true, we hold open and
// reuse SegmentReader instances internally for applying
// deletes, doing merges, and reopening near real-time
// readers.
private volatile boolean poolReaders;
// The instance that was passed to the constructor. It is saved only in order
// to allow users to query an IndexWriter settings.
private final IndexWriterConfig config;
// The PayloadProcessorProvider to use when segments are merged
private PayloadProcessorProvider payloadProcessorProvider;
// for testing
boolean anyNonBulkMerges;
IndexReader getReader() throws IOException {
return getReader(true);
}
/**
* Expert: returns a readonly reader, covering all
* committed as well as un-committed changes to the index.
* This provides "near real-time" searching, in that
* changes made during an IndexWriter session can be
* quickly made available for searching without closing
* the writer nor calling {@link #commit}.
*
* <p>Note that this is functionally equivalent to calling
* {#flush} and then using {@link IndexReader#open} to
* open a new reader. But the turnaround time of this
* method should be faster since it avoids the potentially
* costly {@link #commit}.</p>
*
* <p>You must close the {@link IndexReader} returned by
* this method once you are done using it.</p>
*
* <p>It's <i>near</i> real-time because there is no hard
* guarantee on how quickly you can get a new reader after
* making changes with IndexWriter. You'll have to
* experiment in your situation to determine if it's
* fast enough. As this is a new and experimental
* feature, please report back on your findings so we can
* learn, improve and iterate.</p>
*
* <p>The resulting reader supports {@link
* IndexReader#reopen}, but that call will simply forward
* back to this method (though this may change in the
* future).</p>
*
* <p>The very first time this method is called, this
* writer instance will make every effort to pool the
* readers that it opens for doing merges, applying
* deletes, etc. This means additional resources (RAM,
* file descriptors, CPU time) will be consumed.</p>
*
* <p>For lower latency on reopening a reader, you should
* call {@link #setMergedSegmentWarmer} to
* pre-warm a newly merged segment before it's committed
* to the index. This is important for minimizing
* index-to-search delay after a large merge. </p>
*
* <p>If an addIndexes* call is running in another thread,
* then this reader will only search those segments from
* the foreign index that have been successfully copied
* over, so far</p>.
*
* <p><b>NOTE</b>: Once the writer is closed, any
* outstanding readers may continue to be used. However,
* if you attempt to reopen any of those readers, you'll
* hit an {@link AlreadyClosedException}.</p>
*
* @lucene.experimental
*
* @return IndexReader that covers entire index plus all
* changes made so far by this IndexWriter instance
*
* @throws IOException
*/
IndexReader getReader(boolean applyAllDeletes) throws IOException {
ensureOpen();
final long tStart = System.currentTimeMillis();
if (infoStream != null) {
message("flush at getReader");
}
// Do this up front before flushing so that the readers
// obtained during this flush are pooled, the first time
// this method is called:
poolReaders = true;
// Prevent segmentInfos from changing while opening the
// reader; in theory we could do similar retry logic,
// just like we do when loading segments_N
IndexReader r;
synchronized(this) {
flush(false, applyAllDeletes);
r = new DirectoryReader(this, segmentInfos, config.getReaderTermsIndexDivisor(), codecs, applyAllDeletes);
if (infoStream != null) {
message("return reader version=" + r.getVersion() + " reader=" + r);
}
}
maybeMerge();
if (infoStream != null) {
message("getReader took " + (System.currentTimeMillis() - tStart) + " msec");
}
return r;
}
// Used for all SegmentReaders we open
private final Collection<IndexReader.ReaderFinishedListener> readerFinishedListeners = new MapBackedSet<IndexReader.ReaderFinishedListener>(new ConcurrentHashMap<IndexReader.ReaderFinishedListener,Boolean>());
Collection<IndexReader.ReaderFinishedListener> getReaderFinishedListeners() throws IOException {
return readerFinishedListeners;
}
/** Holds shared SegmentReader instances. IndexWriter uses
* SegmentReaders for 1) applying deletes, 2) doing
* merges, 3) handing out a real-time reader. This pool
* reuses instances of the SegmentReaders in all these
* places if it is in "near real-time mode" (getReader()
* has been called on this instance). */
class ReaderPool {
private final Map<SegmentInfo,SegmentReader> readerMap = new HashMap<SegmentInfo,SegmentReader>();
/** Forcefully clear changes for the specified segments. This is called on successful merge. */
synchronized void clear(SegmentInfos infos) throws IOException {
if (infos == null) {
for (Map.Entry<SegmentInfo,SegmentReader> ent: readerMap.entrySet()) {
ent.getValue().hasChanges = false;
}
} else {
for (final SegmentInfo info: infos) {
final SegmentReader r = readerMap.get(info);
if (r != null) {
r.hasChanges = false;
}
}
}
}
// used only by asserts
public synchronized boolean infoIsLive(SegmentInfo info) {
int idx = segmentInfos.indexOf(info);
assert idx != -1: "info=" + info + " isn't in pool";
assert segmentInfos.get(idx) == info: "info=" + info + " doesn't match live info in segmentInfos";
return true;
}
public synchronized SegmentInfo mapToLive(SegmentInfo info) {
int idx = segmentInfos.indexOf(info);
if (idx != -1) {
info = segmentInfos.get(idx);
}
return info;
}
/**
* Release the segment reader (i.e. decRef it and close if there
* are no more references.
* @return true if this release altered the index (eg
* the SegmentReader had pending changes to del docs and
* was closed). Caller must call checkpoint() if so.
* @param sr
* @throws IOException
*/
public synchronized boolean release(SegmentReader sr) throws IOException {
return release(sr, false);
}
/**
* Release the segment reader (i.e. decRef it and close if there
* are no more references.
* @return true if this release altered the index (eg
* the SegmentReader had pending changes to del docs and
* was closed). Caller must call checkpoint() if so.
* @param sr
* @throws IOException
*/
public synchronized boolean release(SegmentReader sr, boolean drop) throws IOException {
final boolean pooled = readerMap.containsKey(sr.getSegmentInfo());
assert !pooled || readerMap.get(sr.getSegmentInfo()) == sr;
// Drop caller's ref; for an external reader (not
// pooled), this decRef will close it
sr.decRef();
if (pooled && (drop || (!poolReaders && sr.getRefCount() == 1))) {
// We invoke deleter.checkpoint below, so we must be
// sync'd on IW if there are changes:
assert !sr.hasChanges || Thread.holdsLock(IndexWriter.this);
// Discard (don't save) changes when we are dropping
// the reader; this is used only on the sub-readers
// after a successful merge.
sr.hasChanges &= !drop;
final boolean hasChanges = sr.hasChanges;
// Drop our ref -- this will commit any pending
// changes to the dir
sr.close();
// We are the last ref to this reader; since we're
// not pooling readers, we release it:
readerMap.remove(sr.getSegmentInfo());
return hasChanges;
}
return false;
}
public synchronized void drop(SegmentInfos infos) throws IOException {
for(SegmentInfo info : infos) {
drop(info);
}
}
public synchronized void drop(SegmentInfo info) throws IOException {
final SegmentReader sr = readerMap.get(info);
if (sr != null) {
sr.hasChanges = false;
readerMap.remove(info);
sr.close();
}
}
/** Remove all our references to readers, and commits
* any pending changes. */
synchronized void close() throws IOException {
// We invoke deleter.checkpoint below, so we must be
// sync'd on IW:
assert Thread.holdsLock(IndexWriter.this);
Iterator<Map.Entry<SegmentInfo,SegmentReader>> iter = readerMap.entrySet().iterator();
while (iter.hasNext()) {
Map.Entry<SegmentInfo,SegmentReader> ent = iter.next();
SegmentReader sr = ent.getValue();
if (sr.hasChanges) {
assert infoIsLive(sr.getSegmentInfo());
sr.doCommit(null);
// Must checkpoint w/ deleter, because this
// segment reader will have created new _X_N.del
// file.
deleter.checkpoint(segmentInfos, false);
}
iter.remove();
// NOTE: it is allowed that this decRef does not
// actually close the SR; this can happen when a
// near real-time reader is kept open after the
// IndexWriter instance is closed
sr.decRef();
}
}
/**
* Commit all segment reader in the pool.
* @throws IOException
*/
synchronized void commit(SegmentInfos infos) throws IOException {
// We invoke deleter.checkpoint below, so we must be
// sync'd on IW:
assert Thread.holdsLock(IndexWriter.this);
for (SegmentInfo info : infos) {
final SegmentReader sr = readerMap.get(info);
if (sr != null && sr.hasChanges) {
assert infoIsLive(info);
sr.doCommit(null);
// Must checkpoint w/ deleter, because this
// segment reader will have created new _X_N.del
// file.
deleter.checkpoint(segmentInfos, false);
}
}
}
/**
* Returns a ref to a clone. NOTE: this clone is not
* enrolled in the pool, so you should simply close()
* it when you're done (ie, do not call release()).
*/
public synchronized SegmentReader getReadOnlyClone(SegmentInfo info, boolean doOpenStores, int termInfosIndexDivisor) throws IOException {
SegmentReader sr = get(info, doOpenStores, BufferedIndexInput.BUFFER_SIZE, termInfosIndexDivisor);
try {
return (SegmentReader) sr.clone(true);
} finally {
sr.decRef();
}
}
/**
* Obtain a SegmentReader from the readerPool. The reader
* must be returned by calling {@link #release(SegmentReader)}
* @see #release(SegmentReader)
* @param info
* @param doOpenStores
* @throws IOException
*/
public synchronized SegmentReader get(SegmentInfo info, boolean doOpenStores) throws IOException {
return get(info, doOpenStores, BufferedIndexInput.BUFFER_SIZE, config.getReaderTermsIndexDivisor());
}
/**
* Obtain a SegmentReader from the readerPool. The reader
* must be returned by calling {@link #release(SegmentReader)}
*
* @see #release(SegmentReader)
* @param info
* @param doOpenStores
* @param readBufferSize
* @param termsIndexDivisor
* @throws IOException
*/
public synchronized SegmentReader get(SegmentInfo info, boolean doOpenStores, int readBufferSize, int termsIndexDivisor) throws IOException {
if (poolReaders) {
readBufferSize = BufferedIndexInput.BUFFER_SIZE;
}
SegmentReader sr = readerMap.get(info);
if (sr == null) {
// TODO: we may want to avoid doing this while
// synchronized
// Returns a ref, which we xfer to readerMap:
sr = SegmentReader.get(false, info.dir, info, readBufferSize, doOpenStores, termsIndexDivisor);
sr.readerFinishedListeners = readerFinishedListeners;
if (info.dir == directory) {
// Only pool if reader is not external
readerMap.put(info, sr);
}
} else {
if (doOpenStores) {
sr.openDocStores();
}
if (termsIndexDivisor != -1) {
// If this reader was originally opened because we
// needed to merge it, we didn't load the terms
// index. But now, if the caller wants the terms
// index (eg because it's doing deletes, or an NRT
// reader is being opened) we ask the reader to
// load its terms index.
sr.loadTermsIndex(termsIndexDivisor);
}
}
// Return a ref to our caller
if (info.dir == directory) {
// Only incRef if we pooled (reader is not external)
sr.incRef();
}
return sr;
}
// Returns a ref
public synchronized SegmentReader getIfExists(SegmentInfo info) throws IOException {
SegmentReader sr = readerMap.get(info);
if (sr != null) {
sr.incRef();
}
return sr;
}
}
/**
* Obtain the number of deleted docs for a pooled reader.
* If the reader isn't being pooled, the segmentInfo's
* delCount is returned.
*/
public int numDeletedDocs(SegmentInfo info) throws IOException {
SegmentReader reader = readerPool.getIfExists(info);
try {
if (reader != null) {
return reader.numDeletedDocs();
} else {
return info.getDelCount();
}
} finally {
if (reader != null) {
readerPool.release(reader);
}
}
}
/**
* Used internally to throw an {@link
* AlreadyClosedException} if this IndexWriter has been
* closed.
* @throws AlreadyClosedException if this IndexWriter is closed
*/
protected final void ensureOpen(boolean includePendingClose) throws AlreadyClosedException {
if (closed || (includePendingClose && closing)) {
throw new AlreadyClosedException("this IndexWriter is closed");
}
}
protected final void ensureOpen() throws AlreadyClosedException {
ensureOpen(true);
}
/**
* Prints a message to the infoStream (if non-null),
* prefixed with the identifying information for this
* writer and the thread that's calling it.
*/
public void message(String message) {
if (infoStream != null)
infoStream.println("IW " + messageID + " [" + new Date() + "; " + Thread.currentThread().getName() + "]: " + message);
}
CodecProvider codecs;
/**
* Constructs a new IndexWriter per the settings given in <code>conf</code>.
* Note that the passed in {@link IndexWriterConfig} is
* privately cloned; if you need to make subsequent "live"
* changes to the configuration use {@link #getConfig}.
* <p>
*
* @param d
* the index directory. The index is either created or appended
* according <code>conf.getOpenMode()</code>.
* @param conf
* the configuration settings according to which IndexWriter should
* be initialized.
* @throws CorruptIndexException
* if the index is corrupt
* @throws LockObtainFailedException
* if another writer has this index open (<code>write.lock</code>
* could not be obtained)
* @throws IOException
* if the directory cannot be read/written to, or if it does not
* exist and <code>conf.getOpenMode()</code> is
* <code>OpenMode.APPEND</code> or if there is any other low-level
* IO error
*/
public IndexWriter(Directory d, IndexWriterConfig conf)
throws CorruptIndexException, LockObtainFailedException, IOException {
config = (IndexWriterConfig) conf.clone();
directory = d;
analyzer = conf.getAnalyzer();
infoStream = defaultInfoStream;
mergePolicy = conf.getMergePolicy();
mergePolicy.setIndexWriter(this);
mergeScheduler = conf.getMergeScheduler();
codecs = conf.getCodecProvider();
bufferedDeletesStream = new BufferedDeletesStream(messageID);
bufferedDeletesStream.setInfoStream(infoStream);
poolReaders = conf.getReaderPooling();
OpenMode mode = conf.getOpenMode();
boolean create;
if (mode == OpenMode.CREATE) {
create = true;
} else if (mode == OpenMode.APPEND) {
create = false;
} else {
// CREATE_OR_APPEND - create only if an index does not exist
create = !IndexReader.indexExists(directory);
}
writeLock = directory.makeLock(WRITE_LOCK_NAME);
if (!writeLock.obtain(conf.getWriteLockTimeout())) // obtain write lock
throw new LockObtainFailedException("Index locked for write: " + writeLock);
boolean success = false;
// If index is too old, reading the segments will throw
// IndexFormatTooOldException.
segmentInfos = new SegmentInfos(codecs);
try {
if (create) {
// Try to read first. This is to allow create
// against an index that's currently open for
// searching. In this case we write the next
// segments_N file with no segments:
try {
segmentInfos.read(directory, codecs);
segmentInfos.clear();
} catch (IOException e) {
// Likely this means it's a fresh directory
}
// Record that we have a change (zero out all
// segments) pending:
changeCount++;
segmentInfos.changed();
} else {
segmentInfos.read(directory, codecs);
IndexCommit commit = conf.getIndexCommit();
if (commit != null) {
// Swap out all segments, but, keep metadata in
// SegmentInfos, like version & generation, to
// preserve write-once. This is important if
// readers are open against the future commit
// points.
if (commit.getDirectory() != directory)
throw new IllegalArgumentException("IndexCommit's directory doesn't match my directory");
SegmentInfos oldInfos = new SegmentInfos(codecs);
oldInfos.read(directory, commit.getSegmentsFileName(), codecs);
segmentInfos.replace(oldInfos);
changeCount++;
segmentInfos.changed();
if (infoStream != null)
message("init: loaded commit \"" + commit.getSegmentsFileName() + "\"");
}
}
setRollbackSegmentInfos(segmentInfos);
// start with previous field numbers, but new FieldInfos
globalFieldNumberMap = segmentInfos.getOrLoadGlobalFieldNumberMap(directory);
docWriter = new DocumentsWriter(config, directory, this, conf.getIndexingChain(),
globalFieldNumberMap.newFieldInfos(SegmentCodecsBuilder.create(codecs)), bufferedDeletesStream);
docWriter.setInfoStream(infoStream);
// Default deleter (for backwards compatibility) is
// KeepOnlyLastCommitDeleter:
deleter = new IndexFileDeleter(directory,
conf.getIndexDeletionPolicy(),
segmentInfos, infoStream, codecs);
if (deleter.startingCommitDeleted) {
// Deletion policy deleted the "head" commit point.
// We have to mark ourself as changed so that if we
// are closed w/o any further changes we write a new
// segments_N file.
changeCount++;
segmentInfos.changed();
}
if (infoStream != null) {
message("init: create=" + create);
messageState();
}
success = true;
} finally {
if (!success) {
if (infoStream != null) {
message("init: hit exception on init; releasing write lock");
}
try {
writeLock.release();
} catch (Throwable t) {
// don't mask the original exception
}
writeLock = null;
}
}
}
private synchronized void setRollbackSegmentInfos(SegmentInfos infos) {
rollbackSegmentInfos = (SegmentInfos) infos.clone();
}
/**
* Returns the private {@link IndexWriterConfig}, cloned
* from the {@link IndexWriterConfig} passed to
* {@link #IndexWriter(Directory, IndexWriterConfig)}.
* <p>
* <b>NOTE:</b> some settings may be changed on the
* returned {@link IndexWriterConfig}, and will take
* effect in the current IndexWriter instance. See the
* javadocs for the specific setters in {@link
* IndexWriterConfig} for details.
*/
public IndexWriterConfig getConfig() {
return config;
}
/** If non-null, this will be the default infoStream used
* by a newly instantiated IndexWriter.
* @see #setInfoStream
*/
public static void setDefaultInfoStream(PrintStream infoStream) {
IndexWriter.defaultInfoStream = infoStream;
}
/**
* Returns the current default infoStream for newly
* instantiated IndexWriters.
* @see #setDefaultInfoStream
*/
public static PrintStream getDefaultInfoStream() {
return IndexWriter.defaultInfoStream;
}
/** If non-null, information about merges, deletes and a
* message when maxFieldLength is reached will be printed
* to this.
*/
public void setInfoStream(PrintStream infoStream) {
ensureOpen();
this.infoStream = infoStream;
docWriter.setInfoStream(infoStream);
deleter.setInfoStream(infoStream);
bufferedDeletesStream.setInfoStream(infoStream);
if (infoStream != null)
messageState();
}
private void messageState() {
message("\ndir=" + directory + "\n" +
"index=" + segString() + "\n" +
"version=" + Constants.LUCENE_VERSION + "\n" +
config.toString());
}
/**
* Returns the current infoStream in use by this writer.
* @see #setInfoStream
*/
public PrintStream getInfoStream() {
ensureOpen();
return infoStream;
}
/** Returns true if verbosing is enabled (i.e., infoStream != null). */
public boolean verbose() {
return infoStream != null;
}
/**
* Commits all changes to an index and closes all
* associated files. Note that this may be a costly
* operation, so, try to re-use a single writer instead of
* closing and opening a new one. See {@link #commit()} for
* caveats about write caching done by some IO devices.
*
* <p> If an Exception is hit during close, eg due to disk
* full or some other reason, then both the on-disk index
* and the internal state of the IndexWriter instance will
* be consistent. However, the close will not be complete
* even though part of it (flushing buffered documents)
* may have succeeded, so the write lock will still be
* held.</p>
*
* <p> If you can correct the underlying cause (eg free up
* some disk space) then you can call close() again.
* Failing that, if you want to force the write lock to be
* released (dangerous, because you may then lose buffered
* docs in the IndexWriter instance) then you can do
* something like this:</p>
*
* <pre>
* try {
* writer.close();
* } finally {
* if (IndexWriter.isLocked(directory)) {
* IndexWriter.unlock(directory);
* }
* }
* </pre>
*
* after which, you must be certain not to use the writer
* instance anymore.</p>
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer, again. See <a
* href="#OOME">above</a> for details.</p>
*
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void close() throws CorruptIndexException, IOException {
close(true);
}
/**
* Closes the index with or without waiting for currently
* running merges to finish. This is only meaningful when
* using a MergeScheduler that runs merges in background
* threads.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer, again. See <a
* href="#OOME">above</a> for details.</p>
*
* <p><b>NOTE</b>: it is dangerous to always call
* close(false), especially when IndexWriter is not open
* for very long, because this can result in "merge
* starvation" whereby long merges will never have a
* chance to finish. This will cause too many segments in
* your index over time.</p>
*
* @param waitForMerges if true, this call will block
* until all merges complete; else, it will ask all
* running merges to abort, wait until those merges have
* finished (which should be at most a few seconds), and
* then return.
*/
public void close(boolean waitForMerges) throws CorruptIndexException, IOException {
// Ensure that only one thread actually gets to do the closing:
if (shouldClose()) {
// If any methods have hit OutOfMemoryError, then abort
// on close, in case the internal state of IndexWriter
// or DocumentsWriter is corrupt
if (hitOOM)
rollbackInternal();
else
closeInternal(waitForMerges);
}
}
// Returns true if this thread should attempt to close, or
// false if IndexWriter is now closed; else, waits until
// another thread finishes closing
synchronized private boolean shouldClose() {
while(true) {
if (!closed) {
if (!closing) {
closing = true;
return true;
} else {
// Another thread is presently trying to close;
// wait until it finishes one way (closes
// successfully) or another (fails to close)
doWait();
}
} else
return false;
}
}
private void closeInternal(boolean waitForMerges) throws CorruptIndexException, IOException {
try {
if (infoStream != null) {
message("now flush at close waitForMerges=" + waitForMerges);
}
docWriter.close();
// Only allow a new merge to be triggered if we are
// going to wait for merges:
if (!hitOOM) {
flush(waitForMerges, true);
}
if (waitForMerges)
// Give merge scheduler last chance to run, in case
// any pending merges are waiting:
mergeScheduler.merge(this);
mergePolicy.close();
synchronized(this) {
finishMerges(waitForMerges);
stopMerges = true;
}
mergeScheduler.close();
if (infoStream != null)
message("now call final commit()");
if (!hitOOM) {
commitInternal(null);
}
if (infoStream != null)
message("at close: " + segString());
synchronized(this) {
readerPool.close();
docWriter = null;
deleter.close();
}
if (writeLock != null) {
writeLock.release(); // release write lock
writeLock = null;
}
synchronized(this) {
closed = true;
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "closeInternal");
} finally {
synchronized(this) {
closing = false;
notifyAll();
if (!closed) {
if (infoStream != null)
message("hit exception while closing");
}
}
}
}
/** Returns the Directory used by this index. */
public Directory getDirectory() {
// Pass false because the flush during closing calls getDirectory
ensureOpen(false);
return directory;
}
/** Returns the analyzer used by this index. */
public Analyzer getAnalyzer() {
ensureOpen();
return analyzer;
}
/** Returns total number of docs in this index, including
* docs not yet flushed (still in the RAM buffer),
* not counting deletions.
* @see #numDocs */
public synchronized int maxDoc() {
int count;
if (docWriter != null)
count = docWriter.getNumDocs();
else
count = 0;
for (int i = 0; i < segmentInfos.size(); i++)
count += segmentInfos.info(i).docCount;
return count;
}
/** Returns total number of docs in this index, including
* docs not yet flushed (still in the RAM buffer), and
* including deletions. <b>NOTE:</b> buffered deletions
* are not counted. If you really need these to be
* counted you should call {@link #commit()} first.
* @see #numDocs */
public synchronized int numDocs() throws IOException {
int count;
if (docWriter != null)
count = docWriter.getNumDocs();
else
count = 0;
for (int i = 0; i < segmentInfos.size(); i++) {
final SegmentInfo info = segmentInfos.info(i);
count += info.docCount - numDeletedDocs(info);
}
return count;
}
public synchronized boolean hasDeletions() throws IOException {
ensureOpen();
if (bufferedDeletesStream.any()) {
return true;
}
if (docWriter.anyDeletions()) {
return true;
}
for (int i = 0; i < segmentInfos.size(); i++)
if (segmentInfos.info(i).hasDeletions())
return true;
return false;
}
/**
* Adds a document to this index.
*
* <p> Note that if an Exception is hit (for example disk full)
* then the index will be consistent, but this document
* may not have been added. Furthermore, it's possible
* the index will have one segment in non-compound format
* even when using compound files (when a merge has
* partially succeeded).</p>
*
* <p> This method periodically flushes pending documents
* to the Directory (see <a href="#flush">above</a>), and
* also periodically triggers segment merges in the index
* according to the {@link MergePolicy} in use.</p>
*
* <p>Merges temporarily consume space in the
* directory. The amount of space required is up to 1X the
* size of all segments being merged, when no
* readers/searchers are open against the index, and up to
* 2X the size of all segments being merged when
* readers/searchers are open against the index (see
* {@link #optimize()} for details). The sequence of
* primitive merge operations performed is governed by the
* merge policy.
*
* <p>Note that each term in the document can be no longer
* than 16383 characters, otherwise an
* IllegalArgumentException will be thrown.</p>
*
* <p>Note that it's possible to create an invalid Unicode
* string in java if a UTF16 surrogate pair is malformed.
* In this case, the invalid characters are silently
* replaced with the Unicode replacement character
* U+FFFD.</p>
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void addDocument(Document doc) throws CorruptIndexException, IOException {
addDocument(doc, analyzer);
}
/**
* Adds a document to this index, using the provided analyzer instead of the
* value of {@link #getAnalyzer()}.
*
* <p>See {@link #addDocument(Document)} for details on
* index and IndexWriter state after an Exception, and
* flushing/merging temporary free space requirements.</p>
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void addDocument(Document doc, Analyzer analyzer) throws CorruptIndexException, IOException {
ensureOpen();
boolean doFlush = false;
boolean success = false;
try {
try {
doFlush = docWriter.updateDocument(doc, analyzer, null);
success = true;
} finally {
if (!success && infoStream != null)
message("hit exception adding document");
}
if (doFlush)
flush(true, false);
} catch (OutOfMemoryError oom) {
handleOOM(oom, "addDocument");
}
}
/**
* Deletes the document(s) containing <code>term</code>.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param term the term to identify the documents to be deleted
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void deleteDocuments(Term term) throws CorruptIndexException, IOException {
ensureOpen();
try {
if (docWriter.deleteTerm(term, false)) {
flush(true, false);
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "deleteDocuments(Term)");
}
}
/**
* Deletes the document(s) containing any of the
* terms. All deletes are flushed at the same time.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param terms array of terms to identify the documents
* to be deleted
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void deleteDocuments(Term... terms) throws CorruptIndexException, IOException {
ensureOpen();
try {
if (docWriter.deleteTerms(terms)) {
flush(true, false);
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "deleteDocuments(Term..)");
}
}
/**
* Deletes the document(s) matching the provided query.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param query the query to identify the documents to be deleted
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void deleteDocuments(Query query) throws CorruptIndexException, IOException {
ensureOpen();
try {
if (docWriter.deleteQuery(query)) {
flush(true, false);
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "deleteDocuments(Query)");
}
}
/**
* Deletes the document(s) matching any of the provided queries.
* All deletes are flushed at the same time.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param queries array of queries to identify the documents
* to be deleted
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void deleteDocuments(Query... queries) throws CorruptIndexException, IOException {
ensureOpen();
try {
if (docWriter.deleteQueries(queries)) {
flush(true, false);
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "deleteDocuments(Query..)");
}
}
/**
* Updates a document by first deleting the document(s)
* containing <code>term</code> and then adding the new
* document. The delete and then add are atomic as seen
* by a reader on the same index (flush may happen only after
* the add).
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param term the term to identify the document(s) to be
* deleted
* @param doc the document to be added
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void updateDocument(Term term, Document doc) throws CorruptIndexException, IOException {
ensureOpen();
updateDocument(term, doc, getAnalyzer());
}
/**
* Updates a document by first deleting the document(s)
* containing <code>term</code> and then adding the new
* document. The delete and then add are atomic as seen
* by a reader on the same index (flush may happen only after
* the add).
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param term the term to identify the document(s) to be
* deleted
* @param doc the document to be added
* @param analyzer the analyzer to use when analyzing the document
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void updateDocument(Term term, Document doc, Analyzer analyzer)
throws CorruptIndexException, IOException {
ensureOpen();
try {
boolean doFlush = false;
boolean success = false;
try {
doFlush = docWriter.updateDocument(doc, analyzer, term);
success = true;
} finally {
if (!success && infoStream != null)
message("hit exception updating document");
}
if (doFlush) {
flush(true, false);
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "updateDocument");
}
}
// for test purpose
final synchronized int getSegmentCount(){
return segmentInfos.size();
}
// for test purpose
final synchronized int getNumBufferedDocuments(){
return docWriter.getNumDocs();
}
// for test purpose
final synchronized Collection<String> getIndexFileNames() throws IOException {
return segmentInfos.files(directory, true);
}
// for test purpose
final synchronized int getDocCount(int i) {
if (i >= 0 && i < segmentInfos.size()) {
return segmentInfos.info(i).docCount;
} else {
return -1;
}
}
// for test purpose
final int getFlushCount() {
return flushCount.get();
}
// for test purpose
final int getFlushDeletesCount() {
return flushDeletesCount.get();
}
final String newSegmentName() {
// Cannot synchronize on IndexWriter because that causes
// deadlock
synchronized(segmentInfos) {
// Important to increment changeCount so that the
// segmentInfos is written on close. Otherwise we
// could close, re-open and re-return the same segment
// name that was previously returned which can cause
// problems at least with ConcurrentMergeScheduler.
changeCount++;
segmentInfos.changed();
return "_" + Integer.toString(segmentInfos.counter++, Character.MAX_RADIX);
}
}
/** If non-null, information about merges will be printed to this.
*/
private PrintStream infoStream;
private static PrintStream defaultInfoStream;
/**
* Requests an "optimize" operation on an index, priming the index
* for the fastest available search. Traditionally this has meant
* merging all segments into a single segment as is done in the
* default merge policy, but individual merge policies may implement
* optimize in different ways.
*
* <p> Optimize is a fairly costly operation, so you
* should only do it if your search performance really
* requires it. Many search applications do fine never
* calling optimize. </p>
*
* <p>Note that optimize requires 2X the index size free
* space in your Directory (3X if you're using compound
* file format). For example, if your index size is 10 MB
* then you need 20 MB free for optimize to complete (30
* MB if you're using compound file format). Also,
* it's best to call {@link #commit()} after the optimize
* completes to allow IndexWriter to free up disk space.</p>
*
* <p>If some but not all readers re-open while an
* optimize is underway, this will cause > 2X temporary
* space to be consumed as those new readers will then
* hold open the partially optimized segments at that
* time. It is best not to re-open readers while optimize
* is running.</p>
*
* <p>The actual temporary usage could be much less than
* these figures (it depends on many factors).</p>
*
* <p>In general, once the optimize completes, the total size of the
* index will be less than the size of the starting index.
* It could be quite a bit smaller (if there were many
* pending deletes) or just slightly smaller.</p>
*
* <p>If an Exception is hit during optimize(), for example
* due to disk full, the index will not be corrupt and no
* documents will have been lost. However, it may have
* been partially optimized (some segments were merged but
* not all), and it's possible that one of the segments in
* the index will be in non-compound format even when
* using compound file format. This will occur when the
* Exception is hit during conversion of the segment into
* compound format.</p>
*
* <p>This call will optimize those segments present in
* the index when the call started. If other threads are
* still adding documents and flushing segments, those
* newly created segments will not be optimized unless you
* call optimize again.</p>
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* <p><b>NOTE</b>: if you call {@link #close(boolean)}
* with <tt>false</tt>, which aborts all running merges,
* then any thread still running this method might hit a
* {@link MergePolicy.MergeAbortedException}.
*
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
* @see MergePolicy#findMergesForOptimize
*/
public void optimize() throws CorruptIndexException, IOException {
optimize(true);
}
/**
* Optimize the index down to <= maxNumSegments. If
* maxNumSegments==1 then this is the same as {@link
* #optimize()}.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param maxNumSegments maximum number of segments left
* in the index after optimization finishes
*/
public void optimize(int maxNumSegments) throws CorruptIndexException, IOException {
optimize(maxNumSegments, true);
}
/** Just like {@link #optimize()}, except you can specify
* whether the call should block until the optimize
* completes. This is only meaningful with a
* {@link MergeScheduler} that is able to run merges in
* background threads.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*/
public void optimize(boolean doWait) throws CorruptIndexException, IOException {
optimize(1, doWait);
}
/** Just like {@link #optimize(int)}, except you can
* specify whether the call should block until the
* optimize completes. This is only meaningful with a
* {@link MergeScheduler} that is able to run merges in
* background threads.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*/
public void optimize(int maxNumSegments, boolean doWait) throws CorruptIndexException, IOException {
ensureOpen();
if (maxNumSegments < 1)
throw new IllegalArgumentException("maxNumSegments must be >= 1; got " + maxNumSegments);
if (infoStream != null) {
message("optimize: index now " + segString());
message("now flush at optimize");
}
flush(true, true);
synchronized(this) {
resetMergeExceptions();
segmentsToOptimize = new HashSet<SegmentInfo>(segmentInfos);
optimizeMaxNumSegments = maxNumSegments;
// Now mark all pending & running merges as optimize
// merge:
for(final MergePolicy.OneMerge merge : pendingMerges) {
merge.optimize = true;
merge.maxNumSegmentsOptimize = maxNumSegments;
}
for ( final MergePolicy.OneMerge merge: runningMerges ) {
merge.optimize = true;
merge.maxNumSegmentsOptimize = maxNumSegments;
}
}
maybeMerge(maxNumSegments, true);
if (doWait) {
synchronized(this) {
while(true) {
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot complete optimize");
}
if (mergeExceptions.size() > 0) {
// Forward any exceptions in background merge
// threads to the current thread:
final int size = mergeExceptions.size();
for(int i=0;i<size;i++) {
final MergePolicy.OneMerge merge = mergeExceptions.get(i);
if (merge.optimize) {
IOException err = new IOException("background merge hit exception: " + merge.segString(directory));
final Throwable t = merge.getException();
if (t != null)
err.initCause(t);
throw err;
}
}
}
if (optimizeMergesPending())
doWait();
else
break;
}
}
// If close is called while we are still
// running, throw an exception so the calling
// thread will know the optimize did not
// complete
ensureOpen();
}
// NOTE: in the ConcurrentMergeScheduler case, when
// doWait is false, we can return immediately while
// background threads accomplish the optimization
}
/** Returns true if any merges in pendingMerges or
* runningMerges are optimization merges. */
private synchronized boolean optimizeMergesPending() {
for (final MergePolicy.OneMerge merge : pendingMerges) {
if (merge.optimize)
return true;
}
for (final MergePolicy.OneMerge merge : runningMerges) {
if (merge.optimize)
return true;
}
return false;
}
/** Just like {@link #expungeDeletes()}, except you can
* specify whether the call should block until the
* operation completes. This is only meaningful with a
* {@link MergeScheduler} that is able to run merges in
* background threads.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* <p><b>NOTE</b>: if you call {@link #close(boolean)}
* with <tt>false</tt>, which aborts all running merges,
* then any thread still running this method might hit a
* {@link MergePolicy.MergeAbortedException}.
*/
public void expungeDeletes(boolean doWait)
throws CorruptIndexException, IOException {
ensureOpen();
if (infoStream != null)
message("expungeDeletes: index now " + segString());
MergePolicy.MergeSpecification spec;
synchronized(this) {
spec = mergePolicy.findMergesToExpungeDeletes(segmentInfos);
if (spec != null) {
final int numMerges = spec.merges.size();
for(int i=0;i<numMerges;i++)
registerMerge(spec.merges.get(i));
}
}
mergeScheduler.merge(this);
if (spec != null && doWait) {
final int numMerges = spec.merges.size();
synchronized(this) {
boolean running = true;
while(running) {
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot complete expungeDeletes");
}
// Check each merge that MergePolicy asked us to
// do, to see if any of them are still running and
// if any of them have hit an exception.
running = false;
for(int i=0;i<numMerges;i++) {
final MergePolicy.OneMerge merge = spec.merges.get(i);
if (pendingMerges.contains(merge) || runningMerges.contains(merge))
running = true;
Throwable t = merge.getException();
if (t != null) {
IOException ioe = new IOException("background merge hit exception: " + merge.segString(directory));
ioe.initCause(t);
throw ioe;
}
}
// If any of our merges are still running, wait:
if (running)
doWait();
}
}
}
// NOTE: in the ConcurrentMergeScheduler case, when
// doWait is false, we can return immediately while
// background threads accomplish the optimization
}
/** Expunges all deletes from the index. When an index
* has many document deletions (or updates to existing
* documents), it's best to either call optimize or
* expungeDeletes to remove all unused data in the index
* associated with the deleted documents. To see how
* many deletions you have pending in your index, call
* {@link IndexReader#numDeletedDocs}
* This saves disk space and memory usage while
* searching. expungeDeletes should be somewhat faster
* than optimize since it does not insist on reducing the
* index to a single segment (though, this depends on the
* {@link MergePolicy}; see {@link
* MergePolicy#findMergesToExpungeDeletes}.). Note that
* this call does not first commit any buffered
* documents, so you must do so yourself if necessary.
* See also {@link #expungeDeletes(boolean)}
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*/
public void expungeDeletes() throws CorruptIndexException, IOException {
expungeDeletes(true);
}
/**
* Expert: asks the mergePolicy whether any merges are
* necessary now and if so, runs the requested merges and
* then iterate (test again if merges are needed) until no
* more merges are returned by the mergePolicy.
*
* Explicit calls to maybeMerge() are usually not
* necessary. The most common case is when merge policy
* parameters have changed.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*/
public final void maybeMerge() throws CorruptIndexException, IOException {
maybeMerge(false);
}
private final void maybeMerge(boolean optimize) throws CorruptIndexException, IOException {
maybeMerge(1, optimize);
}
private final void maybeMerge(int maxNumSegmentsOptimize, boolean optimize) throws CorruptIndexException, IOException {
updatePendingMerges(maxNumSegmentsOptimize, optimize);
mergeScheduler.merge(this);
}
private synchronized void updatePendingMerges(int maxNumSegmentsOptimize, boolean optimize)
throws CorruptIndexException, IOException {
assert !optimize || maxNumSegmentsOptimize > 0;
if (stopMerges) {
return;
}
// Do not start new merges if we've hit OOME
if (hitOOM) {
return;
}
final MergePolicy.MergeSpecification spec;
if (optimize) {
spec = mergePolicy.findMergesForOptimize(segmentInfos, maxNumSegmentsOptimize, segmentsToOptimize);
if (spec != null) {
final int numMerges = spec.merges.size();
for(int i=0;i<numMerges;i++) {
final MergePolicy.OneMerge merge = spec.merges.get(i);
merge.optimize = true;
merge.maxNumSegmentsOptimize = maxNumSegmentsOptimize;
}
}
} else {
spec = mergePolicy.findMerges(segmentInfos);
}
if (spec != null) {
final int numMerges = spec.merges.size();
for(int i=0;i<numMerges;i++) {
registerMerge(spec.merges.get(i));
}
}
}
/** Expert: to be used by a {@link MergePolicy} to avoid
* selecting merges for segments already being merged.
* The returned collection is not cloned, and thus is
* only safe to access if you hold IndexWriter's lock
* (which you do when IndexWriter invokes the
* MergePolicy).
*
* <p>Do not alter the returned collection! */
public synchronized Collection<SegmentInfo> getMergingSegments() {
return mergingSegments;
}
/** Expert: the {@link MergeScheduler} calls this method
* to retrieve the next merge requested by the
* MergePolicy */
synchronized MergePolicy.OneMerge getNextMerge() {
if (pendingMerges.size() == 0)
return null;
else {
// Advance the merge from pending to running
MergePolicy.OneMerge merge = pendingMerges.removeFirst();
runningMerges.add(merge);
return merge;
}
}
/**
* Close the <code>IndexWriter</code> without committing
* any changes that have occurred since the last commit
* (or since it was opened, if commit hasn't been called).
* This removes any temporary files that had been created,
* after which the state of the index will be the same as
* it was when commit() was last called or when this
* writer was first opened. This also clears a previous
* call to {@link #prepareCommit}.
* @throws IOException if there is a low-level IO error
*/
public void rollback() throws IOException {
ensureOpen();
// Ensure that only one thread actually gets to do the closing:
if (shouldClose())
rollbackInternal();
}
private void rollbackInternal() throws IOException {
boolean success = false;
if (infoStream != null ) {
message("rollback");
}
try {
synchronized(this) {
finishMerges(false);
stopMerges = true;
}
if (infoStream != null ) {
message("rollback: done finish merges");
}
// Must pre-close these two, in case they increment
// changeCount so that we can then set it to false
// before calling closeInternal
mergePolicy.close();
mergeScheduler.close();
bufferedDeletesStream.clear();
synchronized(this) {
if (pendingCommit != null) {
pendingCommit.rollbackCommit(directory);
deleter.decRef(pendingCommit);
pendingCommit = null;
notifyAll();
}
// Keep the same segmentInfos instance but replace all
// of its SegmentInfo instances. This is so the next
// attempt to commit using this instance of IndexWriter
// will always write to a new generation ("write
// once").
segmentInfos.clear();
segmentInfos.addAll(rollbackSegmentInfos);
docWriter.abort();
assert testPoint("rollback before checkpoint");
// Ask deleter to locate unreferenced files & remove
// them:
deleter.checkpoint(segmentInfos, false);
deleter.refresh();
}
// Don't bother saving any changes in our segmentInfos
readerPool.clear(null);
lastCommitChangeCount = changeCount;
success = true;
} catch (OutOfMemoryError oom) {
handleOOM(oom, "rollbackInternal");
} finally {
synchronized(this) {
if (!success) {
closing = false;
notifyAll();
if (infoStream != null)
message("hit exception during rollback");
}
}
}
closeInternal(false);
}
/**
* Delete all documents in the index.
*
* <p>This method will drop all buffered documents and will
* remove all segments from the index. This change will not be
* visible until a {@link #commit()} has been called. This method
* can be rolled back using {@link #rollback()}.</p>
*
* <p>NOTE: this method is much faster than using deleteDocuments( new MatchAllDocsQuery() ).</p>
*
* <p>NOTE: this method will forcefully abort all merges
* in progress. If other threads are running {@link
* #optimize()}, {@link #addIndexes(IndexReader[])} or
* {@link #expungeDeletes} methods, they may receive
* {@link MergePolicy.MergeAbortedException}s.
*/
public synchronized void deleteAll() throws IOException {
try {
// Abort any running merges
finishMerges(false);
// Remove any buffered docs
docWriter.abort();
// Remove all segments
segmentInfos.clear();
// Ask deleter to locate unreferenced files & remove them:
deleter.checkpoint(segmentInfos, false);
deleter.refresh();
// Don't bother saving any changes in our segmentInfos
readerPool.clear(null);
// Mark that the index has changed
++changeCount;
segmentInfos.changed();
} catch (OutOfMemoryError oom) {
handleOOM(oom, "deleteAll");
} finally {
if (infoStream != null) {
message("hit exception during deleteAll");
}
}
}
private synchronized void finishMerges(boolean waitForMerges) throws IOException {
if (!waitForMerges) {
stopMerges = true;
// Abort all pending & running merges:
for (final MergePolicy.OneMerge merge : pendingMerges) {
if (infoStream != null)
message("now abort pending merge " + merge.segString(directory));
merge.abort();
mergeFinish(merge);
}
pendingMerges.clear();
for (final MergePolicy.OneMerge merge : runningMerges) {
if (infoStream != null)
message("now abort running merge " + merge.segString(directory));
merge.abort();
}
// These merges periodically check whether they have
// been aborted, and stop if so. We wait here to make
// sure they all stop. It should not take very long
// because the merge threads periodically check if
// they are aborted.
while(runningMerges.size() > 0) {
if (infoStream != null)
message("now wait for " + runningMerges.size() + " running merge to abort");
doWait();
}
stopMerges = false;
notifyAll();
assert 0 == mergingSegments.size();
if (infoStream != null)
message("all running merges have aborted");
} else {
// waitForMerges() will ensure any running addIndexes finishes.
// It's fine if a new one attempts to start because from our
// caller above the call will see that we are in the
// process of closing, and will throw an
// AlreadyClosedException.
waitForMerges();
}
}
/**
* Wait for any currently outstanding merges to finish.
*
* <p>It is guaranteed that any merges started prior to calling this method
* will have completed once this method completes.</p>
*/
public synchronized void waitForMerges() {
if (infoStream != null) {
message("waitForMerges");
}
while(pendingMerges.size() > 0 || runningMerges.size() > 0) {
doWait();
}
// sanity check
assert 0 == mergingSegments.size();
if (infoStream != null) {
message("waitForMerges done");
}
}
/**
* Called whenever the SegmentInfos has been updated and
* the index files referenced exist (correctly) in the
* index directory.
*/
synchronized void checkpoint() throws IOException {
changeCount++;
segmentInfos.changed();
deleter.checkpoint(segmentInfos, false);
}
private synchronized void resetMergeExceptions() {
mergeExceptions = new ArrayList<MergePolicy.OneMerge>();
mergeGen++;
}
private void noDupDirs(Directory... dirs) {
HashSet<Directory> dups = new HashSet<Directory>();
for(int i=0;i<dirs.length;i++) {
if (dups.contains(dirs[i]))
throw new IllegalArgumentException("Directory " + dirs[i] + " appears more than once");
if (dirs[i] == directory)
throw new IllegalArgumentException("Cannot add directory to itself");
dups.add(dirs[i]);
}
}
/**
* Adds all segments from an array of indexes into this index.
*
* <p>This may be used to parallelize batch indexing. A large document
* collection can be broken into sub-collections. Each sub-collection can be
* indexed in parallel, on a different thread, process or machine. The
* complete index can then be created by merging sub-collection indexes
* with this method.
*
* <p>
* <b>NOTE:</b> the index in each {@link Directory} must not be
* changed (opened by a writer) while this method is
* running. This method does not acquire a write lock in
* each input Directory, so it is up to the caller to
* enforce this.
*
* <p>This method is transactional in how Exceptions are
* handled: it does not commit a new segments_N file until
* all indexes are added. This means if an Exception
* occurs (for example disk full), then either no indexes
* will have been added or they all will have been.
*
* <p>Note that this requires temporary free space in the
* {@link Directory} up to 2X the sum of all input indexes
* (including the starting index). If readers/searchers
* are open against the starting index, then temporary
* free space required will be higher by the size of the
* starting index (see {@link #optimize()} for details).
*
* <p>
* <b>NOTE:</b> this method only copies the segments of the incoming indexes
* and does not merge them. Therefore deleted documents are not removed and
* the new segments are not merged with the existing ones. Also, the segments
* are copied as-is, meaning they are not converted to CFS if they aren't,
* and vice-versa. If you wish to do that, you can call {@link #maybeMerge}
* or {@link #optimize} afterwards.
*
* <p>This requires this index not be among those to be added.
*
* <p>
* <b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.
*
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void addIndexes(Directory... dirs) throws CorruptIndexException, IOException {
ensureOpen();
noDupDirs(dirs);
try {
if (infoStream != null)
message("flush at addIndexes(Directory...)");
flush(false, true);
int docCount = 0;
List<SegmentInfo> infos = new ArrayList<SegmentInfo>();
for (Directory dir : dirs) {
if (infoStream != null) {
message("addIndexes: process directory " + dir);
}
SegmentInfos sis = new SegmentInfos(codecs); // read infos from dir
sis.read(dir, codecs);
final Set<String> dsFilesCopied = new HashSet<String>();
final Map<String, String> dsNames = new HashMap<String, String>();
for (SegmentInfo info : sis) {
assert !infos.contains(info): "dup info dir=" + info.dir + " name=" + info.name;
docCount += info.docCount;
String newSegName = newSegmentName();
String dsName = info.getDocStoreSegment();
if (infoStream != null) {
message("addIndexes: process segment origName=" + info.name + " newName=" + newSegName + " dsName=" + dsName + " info=" + info);
}
// Determine if the doc store of this segment needs to be copied. It's
// only relevant for segments who share doc store with others, because
// the DS might have been copied already, in which case we just want
// to update the DS name of this SegmentInfo.
// NOTE: pre-3x segments include a null DSName if they don't share doc
// store. So the following code ensures we don't accidentally insert
// 'null' to the map.
final String newDsName;
if (dsName != null) {
if (dsNames.containsKey(dsName)) {
newDsName = dsNames.get(dsName);
} else {
dsNames.put(dsName, newSegName);
newDsName = newSegName;
}
} else {
newDsName = newSegName;
}
// Copy the segment files
for (String file: info.files()) {
final String newFileName;
if (IndexFileNames.isDocStoreFile(file)) {
newFileName = newDsName + IndexFileNames.stripSegmentName(file);
if (dsFilesCopied.contains(newFileName)) {
continue;
}
dsFilesCopied.add(newFileName);
} else {
newFileName = newSegName + IndexFileNames.stripSegmentName(file);
}
assert !directory.fileExists(newFileName): "file \"" + newFileName + "\" already exists";
dir.copy(directory, file, newFileName);
}
// Update SI appropriately
info.setDocStore(info.getDocStoreOffset(), newDsName, info.getDocStoreIsCompoundFile());
info.dir = directory;
info.name = newSegName;
infos.add(info);
}
}
synchronized (this) {
ensureOpen();
segmentInfos.addAll(infos);
checkpoint();
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "addIndexes(Directory...)");
}
}
/** Merges the provided indexes into this index.
* <p>After this completes, the index is optimized. </p>
* <p>The provided IndexReaders are not closed.</p>
*
* <p><b>NOTE:</b> while this is running, any attempts to
* add or delete documents (with another thread) will be
* paused until this method completes.
*
* <p>See {@link #addIndexes} for details on transactional
* semantics, temporary free space required in the Directory,
* and non-CFS segments on an Exception.</p>
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* <p><b>NOTE</b>: if you call {@link #close(boolean)}
* with <tt>false</tt>, which aborts all running merges,
* then any thread still running this method might hit a
* {@link MergePolicy.MergeAbortedException}.
*
* @throws CorruptIndexException if the index is corrupt
* @throws IOException if there is a low-level IO error
*/
public void addIndexes(IndexReader... readers) throws CorruptIndexException, IOException {
ensureOpen();
try {
if (infoStream != null)
message("flush at addIndexes(IndexReader...)");
flush(false, true);
String mergedName = newSegmentName();
SegmentMerger merger = new SegmentMerger(directory, config.getTermIndexInterval(),
mergedName, null, codecs, payloadProcessorProvider,
globalFieldNumberMap.newFieldInfos(SegmentCodecsBuilder.create(codecs)));
for (IndexReader reader : readers) // add new indexes
merger.add(reader);
int docCount = merger.merge(); // merge 'em
final FieldInfos fieldInfos = merger.fieldInfos();
SegmentInfo info = new SegmentInfo(mergedName, docCount, directory,
false, fieldInfos.hasProx(), merger.getSegmentCodecs(),
fieldInfos.hasVectors(),
fieldInfos);
setDiagnostics(info, "addIndexes(IndexReader...)");
boolean useCompoundFile;
synchronized(this) { // Guard segmentInfos
useCompoundFile = mergePolicy.useCompoundFile(segmentInfos, info);
}
// Now create the compound file if needed
if (useCompoundFile) {
merger.createCompoundFile(mergedName + ".cfs", info);
// delete new non cfs files directly: they were never
// registered with IFD
deleter.deleteNewFiles(info.files());
info.setUseCompoundFile(true);
}
// Register the new segment
synchronized(this) {
segmentInfos.add(info);
checkpoint();
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "addIndexes(IndexReader...)");
}
}
/**
* A hook for extending classes to execute operations after pending added and
* deleted documents have been flushed to the Directory but before the change
* is committed (new segments_N file written).
*/
protected void doAfterFlush() throws IOException {}
/**
* A hook for extending classes to execute operations before pending added and
* deleted documents are flushed to the Directory.
*/
protected void doBeforeFlush() throws IOException {}
/** Expert: prepare for commit.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @see #prepareCommit(Map) */
public final void prepareCommit() throws CorruptIndexException, IOException {
ensureOpen();
prepareCommit(null);
}
/** <p>Expert: prepare for commit, specifying
* commitUserData Map (String -> String). This does the
* first phase of 2-phase commit. This method does all
* steps necessary to commit changes since this writer
* was opened: flushes pending added and deleted docs,
* syncs the index files, writes most of next segments_N
* file. After calling this you must call either {@link
* #commit()} to finish the commit, or {@link
* #rollback()} to revert the commit and undo all changes
* done since the writer was opened.</p>
*
* You can also just call {@link #commit(Map)} directly
* without prepareCommit first in which case that method
* will internally call prepareCommit.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @param commitUserData Opaque Map (String->String)
* that's recorded into the segments file in the index,
* and retrievable by {@link
* IndexReader#getCommitUserData}. Note that when
* IndexWriter commits itself during {@link #close}, the
* commitUserData is unchanged (just carried over from
* the prior commit). If this is null then the previous
* commitUserData is kept. Also, the commitUserData will
* only "stick" if there are actually changes in the
* index to commit.
*/
public final void prepareCommit(Map<String,String> commitUserData) throws CorruptIndexException, IOException {
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot commit");
}
if (pendingCommit != null)
throw new IllegalStateException("prepareCommit was already called with no corresponding call to commit");
if (infoStream != null)
message("prepareCommit: flush");
flush(true, true);
startCommit(commitUserData);
}
// Used only by commit, below; lock order is commitLock -> IW
private final Object commitLock = new Object();
/**
* <p>Commits all pending changes (added & deleted
* documents, optimizations, segment merges, added
* indexes, etc.) to the index, and syncs all referenced
* index files, such that a reader will see the changes
* and the index updates will survive an OS or machine
* crash or power loss. Note that this does not wait for
* any running background merges to finish. This may be a
* costly operation, so you should test the cost in your
* application and do it only when really necessary.</p>
*
* <p> Note that this operation calls Directory.sync on
* the index files. That call should not return until the
* file contents & metadata are on stable storage. For
* FSDirectory, this calls the OS's fsync. But, beware:
* some hardware devices may in fact cache writes even
* during fsync, and return before the bits are actually
* on stable storage, to give the appearance of faster
* performance. If you have such a device, and it does
* not have a battery backup (for example) then on power
* loss it may still lose data. Lucene cannot guarantee
* consistency on such devices. </p>
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*
* @see #prepareCommit
* @see #commit(Map)
*/
public final void commit() throws CorruptIndexException, IOException {
commit(null);
}
/** Commits all changes to the index, specifying a
* commitUserData Map (String -> String). This just
* calls {@link #prepareCommit(Map)} (if you didn't
* already call it) and then {@link #finishCommit}.
*
* <p><b>NOTE</b>: if this method hits an OutOfMemoryError
* you should immediately close the writer. See <a
* href="#OOME">above</a> for details.</p>
*/
public final void commit(Map<String,String> commitUserData) throws CorruptIndexException, IOException {
ensureOpen();
commitInternal(commitUserData);
}
private final void commitInternal(Map<String,String> commitUserData) throws CorruptIndexException, IOException {
if (infoStream != null) {
message("commit: start");
}
synchronized(commitLock) {
if (infoStream != null) {
message("commit: enter lock");
}
if (pendingCommit == null) {
if (infoStream != null) {
message("commit: now prepare");
}
prepareCommit(commitUserData);
} else if (infoStream != null) {
message("commit: already prepared");
}
finishCommit();
}
}
private synchronized final void finishCommit() throws CorruptIndexException, IOException {
if (pendingCommit != null) {
try {
if (infoStream != null)
message("commit: pendingCommit != null");
pendingCommit.finishCommit(directory);
if (infoStream != null)
message("commit: wrote segments file \"" + pendingCommit.getCurrentSegmentFileName() + "\"");
lastCommitChangeCount = pendingCommitChangeCount;
segmentInfos.updateGeneration(pendingCommit);
segmentInfos.setUserData(pendingCommit.getUserData());
setRollbackSegmentInfos(pendingCommit);
deleter.checkpoint(pendingCommit, true);
} finally {
// Matches the incRef done in startCommit:
deleter.decRef(pendingCommit);
pendingCommit = null;
notifyAll();
}
} else if (infoStream != null) {
message("commit: pendingCommit == null; skip");
}
if (infoStream != null) {
message("commit: done");
}
}
/**
* Flush all in-memory buffered updates (adds and deletes)
* to the Directory.
* @param triggerMerge if true, we may merge segments (if
* deletes or docs were flushed) if necessary
* @param applyAllDeletes whether pending deletes should also
*/
protected final void flush(boolean triggerMerge, boolean applyAllDeletes) throws CorruptIndexException, IOException {
// NOTE: this method cannot be sync'd because
// maybeMerge() in turn calls mergeScheduler.merge which
// in turn can take a long time to run and we don't want
// to hold the lock for that. In the case of
// ConcurrentMergeScheduler this can lead to deadlock
// when it stalls due to too many running merges.
// We can be called during close, when closing==true, so we must pass false to ensureOpen:
ensureOpen(false);
if (doFlush(applyAllDeletes) && triggerMerge) {
maybeMerge();
}
}
// TODO: this method should not have to be entirely
// synchronized, ie, merges should be allowed to commit
// even while a flush is happening
private synchronized boolean doFlush(boolean applyAllDeletes) throws CorruptIndexException, IOException {
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot flush");
}
doBeforeFlush();
assert testPoint("startDoFlush");
// We may be flushing because it was triggered by doc
// count, del count, ram usage (in which case flush
// pending is already set), or we may be flushing
// due to external event eg getReader or commit is
// called (in which case we now set it, and this will
// pause all threads):
flushControl.setFlushPendingNoWait("explicit flush");
boolean success = false;
try {
if (infoStream != null) {
message(" start flush: applyAllDeletes=" + applyAllDeletes);
message(" index before flush " + segString());
}
final SegmentInfo newSegment = docWriter.flush(this, deleter, mergePolicy, segmentInfos);
if (newSegment != null) {
setDiagnostics(newSegment, "flush");
segmentInfos.add(newSegment);
checkpoint();
}
if (!applyAllDeletes) {
// If deletes alone are consuming > 1/2 our RAM
// buffer, force them all to apply now. This is to
// prevent too-frequent flushing of a long tail of
// tiny segments:
if (flushControl.getFlushDeletes() ||
(config.getRAMBufferSizeMB() != IndexWriterConfig.DISABLE_AUTO_FLUSH &&
bufferedDeletesStream.bytesUsed() > (1024*1024*config.getRAMBufferSizeMB()/2))) {
applyAllDeletes = true;
if (infoStream != null) {
message("force apply deletes bytesUsed=" + bufferedDeletesStream.bytesUsed() + " vs ramBuffer=" + (1024*1024*config.getRAMBufferSizeMB()));
}
}
}
if (applyAllDeletes) {
if (infoStream != null) {
message("apply all deletes during flush");
}
flushDeletesCount.incrementAndGet();
final BufferedDeletesStream.ApplyDeletesResult result = bufferedDeletesStream.applyDeletes(readerPool, segmentInfos);
if (result.anyDeletes) {
checkpoint();
}
if (!keepFullyDeletedSegments && result.allDeleted != null) {
if (infoStream != null) {
message("drop 100% deleted segments: " + result.allDeleted);
}
for(SegmentInfo info : result.allDeleted) {
// If a merge has already registered for this
// segment, we leave it in the readerPool; the
// merge will skip merging it and will then drop
// it once it's done:
if (!mergingSegments.contains(info)) {
segmentInfos.remove(info);
if (readerPool != null) {
readerPool.drop(info);
}
}
}
checkpoint();
}
bufferedDeletesStream.prune(segmentInfos);
assert !bufferedDeletesStream.any();
flushControl.clearDeletes();
} else if (infoStream != null) {
message("don't apply deletes now delTermCount=" + bufferedDeletesStream.numTerms() + " bytesUsed=" + bufferedDeletesStream.bytesUsed());
}
doAfterFlush();
flushCount.incrementAndGet();
success = true;
return newSegment != null;
} catch (OutOfMemoryError oom) {
handleOOM(oom, "doFlush");
// never hit
return false;
} finally {
flushControl.clearFlushPending();
if (!success && infoStream != null)
message("hit exception during flush");
}
}
/** Expert: Return the total size of all index files currently cached in memory.
* Useful for size management with flushRamDocs()
*/
public final long ramSizeInBytes() {
ensureOpen();
return docWriter.bytesUsed() + bufferedDeletesStream.bytesUsed();
}
/** Expert: Return the number of documents currently
* buffered in RAM. */
public final synchronized int numRamDocs() {
ensureOpen();
return docWriter.getNumDocs();
}
private void ensureValidMerge(MergePolicy.OneMerge merge) {
for(SegmentInfo info : merge.segments) {
if (segmentInfos.indexOf(info) == -1) {
throw new MergePolicy.MergeException("MergePolicy selected a segment (" + info.name + ") that is not in the current index " + segString(), directory);
}
}
}
/** Carefully merges deletes for the segments we just
* merged. This is tricky because, although merging will
* clear all deletes (compacts the documents), new
* deletes may have been flushed to the segments since
* the merge was started. This method "carries over"
* such new deletes onto the newly merged segment, and
* saves the resulting deletes file (incrementing the
* delete generation for merge.info). If no deletes were
* flushed, no new deletes file is saved. */
synchronized private void commitMergedDeletes(MergePolicy.OneMerge merge, SegmentReader mergedReader) throws IOException {
assert testPoint("startCommitMergeDeletes");
final SegmentInfos sourceSegments = merge.segments;
if (infoStream != null)
message("commitMergeDeletes " + merge.segString(directory));
// Carefully merge deletes that occurred after we
// started merging:
int docUpto = 0;
int delCount = 0;
long minGen = Long.MAX_VALUE;
for(int i=0; i < sourceSegments.size(); i++) {
SegmentInfo info = sourceSegments.info(i);
minGen = Math.min(info.getBufferedDeletesGen(), minGen);
int docCount = info.docCount;
final SegmentReader previousReader = merge.readerClones.get(i);
if (previousReader == null) {
// Reader was skipped because it was 100% deletions
continue;
}
final Bits prevDelDocs = previousReader.getDeletedDocs();
final SegmentReader currentReader = merge.readers.get(i);
final Bits currentDelDocs = currentReader.getDeletedDocs();
if (previousReader.hasDeletions()) {
// There were deletes on this segment when the merge
// started. The merge has collapsed away those
// deletes, but, if new deletes were flushed since
// the merge started, we must now carefully keep any
// newly flushed deletes but mapping them to the new
// docIDs.
if (currentReader.numDeletedDocs() > previousReader.numDeletedDocs()) {
// This means this segment has had new deletes
// committed since we started the merge, so we
// must merge them:
for(int j=0;j<docCount;j++) {
if (prevDelDocs.get(j))
assert currentDelDocs.get(j);
else {
if (currentDelDocs.get(j)) {
mergedReader.doDelete(docUpto);
delCount++;
}
docUpto++;
}
}
} else {
docUpto += docCount - previousReader.numDeletedDocs();
}
} else if (currentReader.hasDeletions()) {
// This segment had no deletes before but now it
// does:
for(int j=0; j<docCount; j++) {
if (currentDelDocs.get(j)) {
mergedReader.doDelete(docUpto);
delCount++;
}
docUpto++;
}
} else
// No deletes before or after
docUpto += info.docCount;
}
assert mergedReader.numDeletedDocs() == delCount;
mergedReader.hasChanges = delCount > 0;
// If new deletes were applied while we were merging
// (which happens if eg commit() or getReader() is
// called during our merge), then it better be the case
// that the delGen has increased for all our merged
// segments:
assert !mergedReader.hasChanges || minGen > mergedReader.getSegmentInfo().getBufferedDeletesGen();
mergedReader.getSegmentInfo().setBufferedDeletesGen(minGen);
}
synchronized private boolean commitMerge(MergePolicy.OneMerge merge, SegmentReader mergedReader) throws IOException {
assert testPoint("startCommitMerge");
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot complete merge");
}
if (infoStream != null)
message("commitMerge: " + merge.segString(directory) + " index=" + segString());
assert merge.registerDone;
// If merge was explicitly aborted, or, if rollback() or
// rollbackTransaction() had been called since our merge
// started (which results in an unqualified
// deleter.refresh() call that will remove any index
// file that current segments does not reference), we
// abort this merge
if (merge.isAborted()) {
if (infoStream != null)
message("commitMerge: skipping merge " + merge.segString(directory) + ": it was aborted");
return false;
}
commitMergedDeletes(merge, mergedReader);
// If the doc store we are using has been closed and
// is in now compound format (but wasn't when we
// started), then we will switch to the compound
// format as well:
assert !segmentInfos.contains(merge.info);
final boolean allDeleted = mergedReader.numDocs() == 0;
if (infoStream != null && allDeleted) {
message("merged segment " + merge.info + " is 100% deleted" + (keepFullyDeletedSegments ? "" : "; skipping insert"));
}
final Set mergedAway = new HashSet<SegmentInfo>(merge.segments);
int segIdx = 0;
int newSegIdx = 0;
boolean inserted = false;
final int curSegCount = segmentInfos.size();
while(segIdx < curSegCount) {
final SegmentInfo info = segmentInfos.info(segIdx++);
if (mergedAway.contains(info)) {
if (!inserted && (!allDeleted || keepFullyDeletedSegments)) {
segmentInfos.set(segIdx-1, merge.info);
inserted = true;
newSegIdx++;
}
} else {
segmentInfos.set(newSegIdx++, info);
}
}
// Either we found place to insert segment, or, we did
// not, but only because all segments we merged became
// deleted while we are merging, in which case it should
// be the case that the new segment is also all deleted:
if (!inserted) {
assert allDeleted;
if (keepFullyDeletedSegments) {
segmentInfos.add(0, merge.info);
} else {
readerPool.drop(merge.info);
}
}
segmentInfos.subList(newSegIdx, segmentInfos.size()).clear();
if (infoStream != null) {
message("after commit: " + segString());
}
closeMergeReaders(merge, false);
// Must note the change to segmentInfos so any commits
// in-flight don't lose it:
checkpoint();
// If the merged segments had pending changes, clear
// them so that they don't bother writing them to
// disk, updating SegmentInfo, etc.:
readerPool.clear(merge.segments);
if (merge.optimize) {
// cascade the optimize:
segmentsToOptimize.add(merge.info);
}
return true;
}
final private void handleMergeException(Throwable t, MergePolicy.OneMerge merge) throws IOException {
if (infoStream != null) {
message("handleMergeException: merge=" + merge.segString(directory) + " exc=" + t);
}
// Set the exception on the merge, so if
// optimize() is waiting on us it sees the root
// cause exception:
merge.setException(t);
addMergeException(merge);
if (t instanceof MergePolicy.MergeAbortedException) {
// We can ignore this exception (it happens when
// close(false) or rollback is called), unless the
// merge involves segments from external directories,
// in which case we must throw it so, for example, the
// rollbackTransaction code in addIndexes* is
// executed.
if (merge.isExternal)
throw (MergePolicy.MergeAbortedException) t;
} else if (t instanceof IOException)
throw (IOException) t;
else if (t instanceof RuntimeException)
throw (RuntimeException) t;
else if (t instanceof Error)
throw (Error) t;
else
// Should not get here
throw new RuntimeException(t);
}
/**
* Merges the indicated segments, replacing them in the stack with a
* single segment.
*/
final void merge(MergePolicy.OneMerge merge)
throws CorruptIndexException, IOException {
boolean success = false;
final long t0 = System.currentTimeMillis();
try {
try {
try {
mergeInit(merge);
if (infoStream != null)
message("now merge\n merge=" + merge.segString(directory) + "\n index=" + segString());
mergeMiddle(merge);
mergeSuccess(merge);
success = true;
} catch (Throwable t) {
handleMergeException(t, merge);
}
} finally {
synchronized(this) {
mergeFinish(merge);
if (!success) {
if (infoStream != null)
message("hit exception during merge");
if (merge.info != null && !segmentInfos.contains(merge.info))
deleter.refresh(merge.info.name);
}
// This merge (and, generally, any change to the
// segments) may now enable new merges, so we call
// merge policy & update pending merges.
if (success && !merge.isAborted() && (merge.optimize || (!closed && !closing))) {
updatePendingMerges(merge.maxNumSegmentsOptimize, merge.optimize);
}
}
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "merge");
}
if (infoStream != null && merge.info != null) {
message("merge time " + (System.currentTimeMillis()-t0) + " msec for " + merge.info.docCount + " docs");
}
}
/** Hook that's called when the specified merge is complete. */
void mergeSuccess(MergePolicy.OneMerge merge) {
}
/** Checks whether this merge involves any segments
* already participating in a merge. If not, this merge
* is "registered", meaning we record that its segments
* are now participating in a merge, and true is
* returned. Else (the merge conflicts) false is
* returned. */
final synchronized boolean registerMerge(MergePolicy.OneMerge merge) throws MergePolicy.MergeAbortedException {
if (merge.registerDone)
return true;
if (stopMerges) {
merge.abort();
throw new MergePolicy.MergeAbortedException("merge is aborted: " + merge.segString(directory));
}
final int count = merge.segments.size();
boolean isExternal = false;
for(int i=0;i<count;i++) {
final SegmentInfo info = merge.segments.info(i);
if (mergingSegments.contains(info)) {
return false;
}
if (segmentInfos.indexOf(info) == -1) {
return false;
}
if (info.dir != directory) {
isExternal = true;
}
if (segmentsToOptimize.contains(info)) {
merge.optimize = true;
merge.maxNumSegmentsOptimize = optimizeMaxNumSegments;
}
}
ensureValidMerge(merge);
pendingMerges.add(merge);
if (infoStream != null)
message("add merge to pendingMerges: " + merge.segString(directory) + " [total " + pendingMerges.size() + " pending]");
merge.mergeGen = mergeGen;
merge.isExternal = isExternal;
// OK it does not conflict; now record that this merge
// is running (while synchronized) to avoid race
// condition where two conflicting merges from different
// threads, start
for(int i=0;i<count;i++) {
mergingSegments.add(merge.segments.info(i));
}
// Merge is now registered
merge.registerDone = true;
return true;
}
/** Does initial setup for a merge, which is fast but holds
* the synchronized lock on IndexWriter instance. */
final synchronized void mergeInit(MergePolicy.OneMerge merge) throws IOException {
boolean success = false;
try {
_mergeInit(merge);
success = true;
} finally {
if (!success) {
if (infoStream != null) {
message("hit exception in mergeInit");
}
mergeFinish(merge);
}
}
}
synchronized private void _mergeInit(MergePolicy.OneMerge merge) throws IOException {
assert testPoint("startMergeInit");
assert merge.registerDone;
assert !merge.optimize || merge.maxNumSegmentsOptimize > 0;
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot merge");
}
// TODO: is there any perf benefit to sorting
// merged segments? eg biggest to smallest?
if (merge.info != null)
// mergeInit already done
return;
if (merge.isAborted())
return;
// Bind a new segment name here so even with
// ConcurrentMergePolicy we keep deterministic segment
// names.
merge.info = new SegmentInfo(newSegmentName(), 0, directory, false, false, null, false, globalFieldNumberMap.newFieldInfos(SegmentCodecsBuilder.create(codecs)));
// Lock order: IW -> BD
final BufferedDeletesStream.ApplyDeletesResult result = bufferedDeletesStream.applyDeletes(readerPool, merge.segments);
if (result.anyDeletes) {
checkpoint();
}
if (!keepFullyDeletedSegments && result.allDeleted != null) {
if (infoStream != null) {
message("drop 100% deleted segments: " + result.allDeleted);
}
for(SegmentInfo info : result.allDeleted) {
segmentInfos.remove(info);
if (merge.segments.contains(info)) {
mergingSegments.remove(info);
merge.segments.remove(info);
}
}
if (readerPool != null) {
readerPool.drop(result.allDeleted);
}
checkpoint();
}
merge.info.setBufferedDeletesGen(result.gen);
// Lock order: IW -> BD
bufferedDeletesStream.prune(segmentInfos);
Map<String,String> details = new HashMap<String,String>();
details.put("optimize", Boolean.toString(merge.optimize));
details.put("mergeFactor", Integer.toString(merge.segments.size()));
setDiagnostics(merge.info, "merge", details);
if (infoStream != null) {
message("merge seg=" + merge.info.name);
}
// Also enroll the merged segment into mergingSegments;
// this prevents it from getting selected for a merge
// after our merge is done but while we are building the
// CFS:
mergingSegments.add(merge.info);
}
private void setDiagnostics(SegmentInfo info, String source) {
setDiagnostics(info, source, null);
}
private void setDiagnostics(SegmentInfo info, String source, Map<String,String> details) {
Map<String,String> diagnostics = new HashMap<String,String>();
diagnostics.put("source", source);
diagnostics.put("lucene.version", Constants.LUCENE_VERSION);
diagnostics.put("os", Constants.OS_NAME);
diagnostics.put("os.arch", Constants.OS_ARCH);
diagnostics.put("os.version", Constants.OS_VERSION);
diagnostics.put("java.version", Constants.JAVA_VERSION);
diagnostics.put("java.vendor", Constants.JAVA_VENDOR);
if (details != null) {
diagnostics.putAll(details);
}
info.setDiagnostics(diagnostics);
}
/** Does fininishing for a merge, which is fast but holds
* the synchronized lock on IndexWriter instance. */
final synchronized void mergeFinish(MergePolicy.OneMerge merge) throws IOException {
// Optimize, addIndexes or finishMerges may be waiting
// on merges to finish.
notifyAll();
// It's possible we are called twice, eg if there was an
// exception inside mergeInit
if (merge.registerDone) {
final SegmentInfos sourceSegments = merge.segments;
final int end = sourceSegments.size();
for(int i=0;i<end;i++) {
mergingSegments.remove(sourceSegments.info(i));
}
mergingSegments.remove(merge.info);
merge.registerDone = false;
}
runningMerges.remove(merge);
}
private synchronized void closeMergeReaders(MergePolicy.OneMerge merge, boolean suppressExceptions) throws IOException {
final int numSegments = merge.readers.size();
if (suppressExceptions) {
// Suppress any new exceptions so we throw the
// original cause
boolean anyChanges = false;
for (int i=0;i<numSegments;i++) {
if (merge.readers.get(i) != null) {
try {
anyChanges |= readerPool.release(merge.readers.get(i), false);
} catch (Throwable t) {
}
merge.readers.set(i, null);
}
if (i < merge.readerClones.size() && merge.readerClones.get(i) != null) {
try {
merge.readerClones.get(i).close();
} catch (Throwable t) {
}
// This was a private clone and we had the
// only reference
assert merge.readerClones.get(i).getRefCount() == 0: "refCount should be 0 but is " + merge.readerClones.get(i).getRefCount();
merge.readerClones.set(i, null);
}
}
if (anyChanges) {
checkpoint();
}
} else {
for (int i=0;i<numSegments;i++) {
if (merge.readers.get(i) != null) {
readerPool.release(merge.readers.get(i), true);
merge.readers.set(i, null);
}
if (i < merge.readerClones.size() && merge.readerClones.get(i) != null) {
merge.readerClones.get(i).close();
// This was a private clone and we had the only reference
assert merge.readerClones.get(i).getRefCount() == 0;
merge.readerClones.set(i, null);
}
}
}
}
/** Does the actual (time-consuming) work of the merge,
* but without holding synchronized lock on IndexWriter
* instance */
private int mergeMiddle(MergePolicy.OneMerge merge)
throws CorruptIndexException, IOException {
merge.checkAborted(directory);
final String mergedName = merge.info.name;
int mergedDocCount = 0;
SegmentInfos sourceSegments = merge.segments;
SegmentMerger merger = new SegmentMerger(directory, config.getTermIndexInterval(), mergedName, merge,
codecs, payloadProcessorProvider,
merge.info.getFieldInfos());
if (infoStream != null) {
message("merging " + merge.segString(directory) + " mergeVectors=" + merger.fieldInfos().hasVectors());
}
merge.readers = new ArrayList<SegmentReader>();
merge.readerClones = new ArrayList<SegmentReader>();
// This is try/finally to make sure merger's readers are
// closed:
boolean success = false;
try {
int totDocCount = 0;
int segUpto = 0;
while(segUpto < sourceSegments.size()) {
final SegmentInfo info = sourceSegments.info(segUpto);
// Hold onto the "live" reader; we will use this to
// commit merged deletes
final SegmentReader reader = readerPool.get(info, true,
MERGE_READ_BUFFER_SIZE,
-config.getReaderTermsIndexDivisor());
merge.readers.add(reader);
// We clone the segment readers because other
// deletes may come in while we're merging so we
// need readers that will not change
final SegmentReader clone = (SegmentReader) reader.clone(true);
merge.readerClones.add(clone);
if (clone.numDocs() > 0) {
merger.add(clone);
totDocCount += clone.numDocs();
}
segUpto++;
}
if (infoStream != null) {
message("merge: total " + totDocCount + " docs");
}
merge.checkAborted(directory);
// This is where all the work happens:
mergedDocCount = merge.info.docCount = merger.merge();
// Record which codec was used to write the segment
merge.info.setSegmentCodecs(merger.getSegmentCodecs());
// Record if we have merged vectors
merge.info.setHasVectors(merger.fieldInfos().hasVectors());
if (infoStream != null) {
message("merge segmentCodecs=" + merger.getSegmentCodecs());
message("merge store matchedCount=" + merger.getMatchedSubReaderCount() + " vs " + merge.readers.size());
}
anyNonBulkMerges |= merger.getAnyNonBulkMerges();
assert mergedDocCount == totDocCount: "mergedDocCount=" + mergedDocCount + " vs " + totDocCount;
// Very important to do this before opening the reader
// because codec must know if prox was written for
// this segment:
//System.out.println("merger set hasProx=" + merger.hasProx() + " seg=" + merge.info.name);
merge.info.setHasProx(merger.fieldInfos().hasProx());
boolean useCompoundFile;
synchronized (this) { // Guard segmentInfos
useCompoundFile = mergePolicy.useCompoundFile(segmentInfos, merge.info);
}
if (useCompoundFile) {
success = false;
final String compoundFileName = IndexFileNames.segmentFileName(mergedName, "", IndexFileNames.COMPOUND_FILE_EXTENSION);
try {
if (infoStream != null) {
message("create compound file " + compoundFileName);
}
merger.createCompoundFile(compoundFileName, merge.info);
success = true;
} catch (IOException ioe) {
synchronized(this) {
if (merge.isAborted()) {
// This can happen if rollback or close(false)
// is called -- fall through to logic below to
// remove the partially created CFS:
} else {
handleMergeException(ioe, merge);
}
}
} catch (Throwable t) {
handleMergeException(t, merge);
} finally {
if (!success) {
if (infoStream != null) {
message("hit exception creating compound file during merge");
}
synchronized(this) {
deleter.deleteFile(compoundFileName);
deleter.deleteNewFiles(merge.info.files());
}
}
}
success = false;
synchronized(this) {
// delete new non cfs files directly: they were never
// registered with IFD
deleter.deleteNewFiles(merge.info.files());
if (merge.isAborted()) {
if (infoStream != null) {
message("abort merge after building CFS");
}
deleter.deleteFile(compoundFileName);
return 0;
}
}
merge.info.setUseCompoundFile(true);
}
final IndexReaderWarmer mergedSegmentWarmer = config.getMergedSegmentWarmer();
final int termsIndexDivisor;
final boolean loadDocStores;
if (mergedSegmentWarmer != null) {
// Load terms index & doc stores so the segment
// warmer can run searches, load documents/term
// vectors
termsIndexDivisor = config.getReaderTermsIndexDivisor();
loadDocStores = true;
} else {
termsIndexDivisor = -1;
loadDocStores = false;
}
// TODO: in the non-realtime case, we may want to only
// keep deletes (it's costly to open entire reader
// when we just need deletes)
final SegmentReader mergedReader = readerPool.get(merge.info, loadDocStores, BufferedIndexInput.BUFFER_SIZE, termsIndexDivisor);
try {
if (poolReaders && mergedSegmentWarmer != null) {
mergedSegmentWarmer.warm(mergedReader);
}
if (!commitMerge(merge, mergedReader)) {
// commitMerge will return false if this merge was aborted
return 0;
}
} finally {
synchronized(this) {
if (readerPool.release(mergedReader)) {
// Must checkpoint after releasing the
// mergedReader since it may have written a new
// deletes file:
checkpoint();
}
}
}
success = true;
} finally {
// Readers are already closed in commitMerge if we didn't hit
// an exc:
if (!success) {
closeMergeReaders(merge, true);
}
}
return mergedDocCount;
}
synchronized void addMergeException(MergePolicy.OneMerge merge) {
assert merge.getException() != null;
if (!mergeExceptions.contains(merge) && mergeGen == merge.mergeGen)
mergeExceptions.add(merge);
}
// For test purposes.
final int getBufferedDeleteTermsSize() {
return docWriter.getPendingDeletes().terms.size();
}
// For test purposes.
final int getNumBufferedDeleteTerms() {
return docWriter.getPendingDeletes().numTermDeletes.get();
}
// utility routines for tests
SegmentInfo newestSegment() {
return segmentInfos.size() > 0 ? segmentInfos.info(segmentInfos.size()-1) : null;
}
public synchronized String segString() {
return segString(segmentInfos);
}
private synchronized String segString(SegmentInfos infos) {
StringBuilder buffer = new StringBuilder();
final int count = infos.size();
for(int i = 0; i < count; i++) {
if (i > 0) {
buffer.append(' ');
}
final SegmentInfo info = infos.info(i);
buffer.append(info.toString(directory, 0));
if (info.dir != directory)
buffer.append("**");
}
return buffer.toString();
}
private synchronized void doWait() {
// NOTE: the callers of this method should in theory
// be able to do simply wait(), but, as a defense
// against thread timing hazards where notifyAll()
// fails to be called, we wait for at most 1 second
// and then return so caller can check if wait
// conditions are satisfied:
try {
wait(1000);
} catch (InterruptedException ie) {
throw new ThreadInterruptedException(ie);
}
}
private boolean keepFullyDeletedSegments;
/** Only for testing.
*
* @lucene.internal */
void keepFullyDeletedSegments() {
keepFullyDeletedSegments = true;
}
boolean getKeepFullyDeletedSegments() {
return keepFullyDeletedSegments;
}
// called only from assert
private boolean filesExist(SegmentInfos toSync) throws IOException {
Collection<String> files = toSync.files(directory, false);
for(final String fileName: files) {
assert directory.fileExists(fileName): "file " + fileName + " does not exist";
// If this trips it means we are missing a call to
// .checkpoint somewhere, because by the time we
// are called, deleter should know about every
// file referenced by the current head
// segmentInfos:
assert deleter.exists(fileName): "IndexFileDeleter doesn't know about file " + fileName;
}
return true;
}
/** Walk through all files referenced by the current
* segmentInfos and ask the Directory to sync each file,
* if it wasn't already. If that succeeds, then we
* prepare a new segments_N file but do not fully commit
* it. */
private void startCommit(Map<String,String> commitUserData) throws IOException {
assert testPoint("startStartCommit");
assert pendingCommit == null;
if (hitOOM) {
throw new IllegalStateException("this writer hit an OutOfMemoryError; cannot commit");
}
try {
if (infoStream != null)
message("startCommit(): start");
final SegmentInfos toSync;
final long myChangeCount;
synchronized(this) {
assert lastCommitChangeCount <= changeCount;
myChangeCount = changeCount;
if (changeCount == lastCommitChangeCount) {
if (infoStream != null)
message(" skip startCommit(): no changes pending");
return;
}
// First, we clone & incref the segmentInfos we intend
// to sync, then, without locking, we sync() all files
// referenced by toSync, in the background.
if (infoStream != null)
message("startCommit index=" + segString(segmentInfos) + " changeCount=" + changeCount);
readerPool.commit(segmentInfos);
toSync = (SegmentInfos) segmentInfos.clone();
assert filesExist(toSync);
if (commitUserData != null)
toSync.setUserData(commitUserData);
// This protects the segmentInfos we are now going
// to commit. This is important in case, eg, while
// we are trying to sync all referenced files, a
// merge completes which would otherwise have
// removed the files we are now syncing.
deleter.incRef(toSync, false);
}
assert testPoint("midStartCommit");
try {
// This call can take a long time -- 10s of seconds
// or more. We do it without sync:
directory.sync(toSync.files(directory, false));
assert testPoint("midStartCommit2");
synchronized(this) {
assert pendingCommit == null;
assert segmentInfos.getGeneration() == toSync.getGeneration();
// Exception here means nothing is prepared
// (this method unwinds everything it did on
// an exception)
toSync.prepareCommit(directory);
pendingCommit = toSync;
pendingCommitChangeCount = myChangeCount;
}
if (infoStream != null)
message("done all syncs");
assert testPoint("midStartCommitSuccess");
} finally {
synchronized(this) {
// Have our master segmentInfos record the
// generations we just prepared. We do this
// on error or success so we don't
// double-write a segments_N file.
segmentInfos.updateGeneration(toSync);
if (pendingCommit == null) {
if (infoStream != null) {
message("hit exception committing segments file");
}
deleter.decRef(toSync);
}
}
}
} catch (OutOfMemoryError oom) {
handleOOM(oom, "startCommit");
}
assert testPoint("finishStartCommit");
}
/**
* Returns <code>true</code> iff the index in the named directory is
* currently locked.
* @param directory the directory to check for a lock
* @throws IOException if there is a low-level IO error
*/
public static boolean isLocked(Directory directory) throws IOException {
return directory.makeLock(WRITE_LOCK_NAME).isLocked();
}
/**
* Forcibly unlocks the index in the named directory.
* <P>
* Caution: this should only be used by failure recovery code,
* when it is known that no other process nor thread is in fact
* currently accessing this index.
*/
public static void unlock(Directory directory) throws IOException {
directory.makeLock(IndexWriter.WRITE_LOCK_NAME).release();
}
/** If {@link #getReader} has been called (ie, this writer
* is in near real-time mode), then after a merge
* completes, this class can be invoked to warm the
* reader on the newly merged segment, before the merge
* commits. This is not required for near real-time
* search, but will reduce search latency on opening a
* new near real-time reader after a merge completes.
*
* @lucene.experimental
*
* <p><b>NOTE</b>: warm is called before any deletes have
* been carried over to the merged segment. */
public static abstract class IndexReaderWarmer {
public abstract void warm(IndexReader reader) throws IOException;
}
private void handleOOM(OutOfMemoryError oom, String location) {
if (infoStream != null) {
message("hit OutOfMemoryError inside " + location);
}
hitOOM = true;
throw oom;
}
// Used only by assert for testing. Current points:
// startDoFlush
// startCommitMerge
// startStartCommit
// midStartCommit
// midStartCommit2
// midStartCommitSuccess
// finishStartCommit
// startCommitMergeDeletes
// startMergeInit
// DocumentsWriter.ThreadState.init start
boolean testPoint(String name) {
return true;
}
synchronized boolean nrtIsCurrent(SegmentInfos infos) {
return infos.version == segmentInfos.version && !docWriter.anyChanges() && !bufferedDeletesStream.any();
}
synchronized boolean isClosed() {
return closed;
}
/** Expert: remove any index files that are no longer
* used.
*
* <p> IndexWriter normally deletes unused files itself,
* during indexing. However, on Windows, which disallows
* deletion of open files, if there is a reader open on
* the index then those files cannot be deleted. This is
* fine, because IndexWriter will periodically retry
* the deletion.</p>
*
* <p> However, IndexWriter doesn't try that often: only
* on open, close, flushing a new segment, and finishing
* a merge. If you don't do any of these actions with your
* IndexWriter, you'll see the unused files linger. If
* that's a problem, call this method to delete them
* (once you've closed the open readers that were
* preventing their deletion).
*
* <p> In addition, you can call this method to delete
* unreferenced index commits. This might be useful if you
* are using an {@link IndexDeletionPolicy} which holds
* onto index commits until some criteria are met, but those
* commits are no longer needed. Otherwise, those commits will
* be deleted the next time commit() is called.
*/
public synchronized void deleteUnusedFiles() throws IOException {
deleter.deletePendingFiles();
deleter.revisitPolicy();
}
/**
* Sets the {@link PayloadProcessorProvider} to use when merging payloads.
* Note that the given <code>pcp</code> will be invoked for every segment that
* is merged, not only external ones that are given through
* {@link #addIndexes}. If you want only the payloads of the external segments
* to be processed, you can return <code>null</code> whenever a
* {@link DirPayloadProcessor} is requested for the {@link Directory} of the
* {@link IndexWriter}.
* <p>
* The default is <code>null</code> which means payloads are processed
* normally (copied) during segment merges. You can also unset it by passing
* <code>null</code>.
* <p>
* <b>NOTE:</b> the set {@link PayloadProcessorProvider} will be in effect
* immediately, potentially for already running merges too. If you want to be
* sure it is used for further operations only, such as {@link #addIndexes} or
* {@link #optimize}, you can call {@link #waitForMerges()} before.
*/
public void setPayloadProcessorProvider(PayloadProcessorProvider pcp) {
payloadProcessorProvider = pcp;
}
/**
* Returns the {@link PayloadProcessorProvider} that is used during segment
* merges to process payloads.
*/
public PayloadProcessorProvider getPayloadProcessorProvider() {
return payloadProcessorProvider;
}
// decides when flushes happen
final class FlushControl {
private boolean flushPending;
private boolean flushDeletes;
private int delCount;
private int docCount;
private boolean flushing;
private synchronized boolean setFlushPending(String reason, boolean doWait) {
if (flushPending || flushing) {
if (doWait) {
while(flushPending || flushing) {
try {
wait();
} catch (InterruptedException ie) {
throw new ThreadInterruptedException(ie);
}
}
}
return false;
} else {
if (infoStream != null) {
message("now trigger flush reason=" + reason);
}
flushPending = true;
return flushPending;
}
}
public synchronized void setFlushPendingNoWait(String reason) {
setFlushPending(reason, false);
}
public synchronized boolean getFlushPending() {
return flushPending;
}
public synchronized boolean getFlushDeletes() {
return flushDeletes;
}
public synchronized void clearFlushPending() {
if (infoStream != null) {
message("clearFlushPending");
}
flushPending = false;
flushDeletes = false;
docCount = 0;
notifyAll();
}
public synchronized void clearDeletes() {
delCount = 0;
}
public synchronized boolean waitUpdate(int docInc, int delInc) {
return waitUpdate(docInc, delInc, false);
}
public synchronized boolean waitUpdate(int docInc, int delInc, boolean skipWait) {
while(flushPending) {
try {
wait();
} catch (InterruptedException ie) {
throw new ThreadInterruptedException(ie);
}
}
// skipWait is only used when a thread is BOTH adding
// a doc and buffering a del term, and, the adding of
// the doc already triggered a flush
if (skipWait) {
docCount += docInc;
delCount += delInc;
return false;
}
final int maxBufferedDocs = config.getMaxBufferedDocs();
if (maxBufferedDocs != IndexWriterConfig.DISABLE_AUTO_FLUSH &&
(docCount+docInc) >= maxBufferedDocs) {
return setFlushPending("maxBufferedDocs", true);
}
docCount += docInc;
final int maxBufferedDeleteTerms = config.getMaxBufferedDeleteTerms();
if (maxBufferedDeleteTerms != IndexWriterConfig.DISABLE_AUTO_FLUSH &&
(delCount+delInc) >= maxBufferedDeleteTerms) {
flushDeletes = true;
return setFlushPending("maxBufferedDeleteTerms", true);
}
delCount += delInc;
return flushByRAMUsage("add delete/doc");
}
public synchronized boolean flushByRAMUsage(String reason) {
final double ramBufferSizeMB = config.getRAMBufferSizeMB();
if (ramBufferSizeMB != IndexWriterConfig.DISABLE_AUTO_FLUSH) {
final long limit = (long) (ramBufferSizeMB*1024*1024);
long used = bufferedDeletesStream.bytesUsed() + docWriter.bytesUsed();
if (used >= limit) {
// DocumentsWriter may be able to free up some
// RAM:
// Lock order: FC -> DW
docWriter.balanceRAM();
used = bufferedDeletesStream.bytesUsed() + docWriter.bytesUsed();
if (used >= limit) {
return setFlushPending("ram full: " + reason, false);
}
}
}
return false;
}
}
final FlushControl flushControl = new FlushControl();
}