/*
* 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.
*/
package org.apache.solr.uninverting;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.TimeUnit;
import org.apache.lucene.codecs.PostingsFormat; // javadocs
import org.apache.lucene.index.DocValues;
import org.apache.lucene.index.DocValuesType;
import org.apache.lucene.index.FieldInfo;
import org.apache.lucene.index.LeafReader;
import org.apache.lucene.index.LegacySortedSetDocValues;
import org.apache.lucene.index.LegacySortedSetDocValuesWrapper;
import org.apache.lucene.index.PostingsEnum;
import org.apache.lucene.index.SortedSetDocValues;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.util.Accountable;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.PagedBytes;
import org.apache.lucene.util.StringHelper;
/**
* This class enables fast access to multiple term ords for
* a specified field across all docIDs.
*
* Like FieldCache, it uninverts the index and holds a
* packed data structure in RAM to enable fast access.
* Unlike FieldCache, it can handle multi-valued fields,
* and, it does not hold the term bytes in RAM. Rather, you
* must obtain a TermsEnum from the {@link #getOrdTermsEnum}
* method, and then seek-by-ord to get the term's bytes.
*
* While normally term ords are type long, in this API they are
* int as the internal representation here cannot address
* more than MAX_INT unique terms. Also, typically this
* class is used on fields with relatively few unique terms
* vs the number of documents. In addition, there is an
* internal limit (16 MB) on how many bytes each chunk of
* documents may consume. If you trip this limit you'll hit
* an IllegalStateException.
*
* Deleted documents are skipped during uninversion, and if
* you look them up you'll get 0 ords.
*
* The returned per-document ords do not retain their
* original order in the document. Instead they are returned
* in sorted (by ord, ie term's BytesRef comparator) order. They
* are also de-dup'd (ie if doc has same term more than once
* in this field, you'll only get that ord back once).
*
* This class
* will create its own term index internally, allowing to
* create a wrapped TermsEnum that can handle ord. The
* {@link #getOrdTermsEnum} method then provides this
* wrapped enum.
*
* The RAM consumption of this class can be high!
*
* @lucene.experimental
*/
/*
* Final form of the un-inverted field:
* Each document points to a list of term numbers that are contained in that document.
*
* Term numbers are in sorted order, and are encoded as variable-length deltas from the
* previous term number. Real term numbers start at 2 since 0 and 1 are reserved. A
* term number of 0 signals the end of the termNumber list.
*
* There is a single int[maxDoc()] which either contains a pointer into a byte[] for
* the termNumber lists, or directly contains the termNumber list if it fits in the 4
* bytes of an integer. If the first byte in the integer is 1, the next 3 bytes
* are a pointer into a byte[] where the termNumber list starts.
*
* There are actually 256 byte arrays, to compensate for the fact that the pointers
* into the byte arrays are only 3 bytes long. The correct byte array for a document
* is a function of its id.
*
* To save space and speed up faceting, any term that matches enough documents will
* not be un-inverted... it will be skipped while building the un-inverted field structure,
* and will use a set intersection method during faceting.
*
* To further save memory, the terms (the actual string values) are not all stored in
* memory, but a TermIndex is used to convert term numbers to term values only
* for the terms needed after faceting has completed. Only every 128th term value
* is stored, along with its corresponding term number, and this is used as an
* index to find the closest term and iterate until the desired number is hit (very
* much like Lucene's own internal term index).
*
*/
public class DocTermOrds implements Accountable {
// Term ords are shifted by this, internally, to reserve
// values 0 (end term) and 1 (index is a pointer into byte array)
private final static int TNUM_OFFSET = 2;
/** Every 128th term is indexed, by default. */
public final static int DEFAULT_INDEX_INTERVAL_BITS = 7; // decrease to a low number like 2 for testing
private int indexIntervalBits;
private int indexIntervalMask;
private int indexInterval;
/** Don't uninvert terms that exceed this count. */
protected final int maxTermDocFreq;
/** Field we are uninverting. */
protected final String field;
/** Number of terms in the field. */
protected int numTermsInField;
/** Total number of references to term numbers. */
protected long termInstances;
private long memsz;
/** Total time to uninvert the field. */
protected int total_time;
/** Time for phase1 of the uninvert process. */
protected int phase1_time;
/** Holds the per-document ords or a pointer to the ords. */
protected int[] index;
/** Holds term ords for documents. */
protected byte[][] tnums = new byte[256][];
/** Total bytes (sum of term lengths) for all indexed terms.*/
protected long sizeOfIndexedStrings;
/** Holds the indexed (by default every 128th) terms. */
protected BytesRef[] indexedTermsArray = new BytesRef[0];
/** If non-null, only terms matching this prefix were
* indexed. */
protected BytesRef prefix;
/** Ordinal of the first term in the field, or 0 if the
* {@link PostingsFormat} does not implement {@link
* TermsEnum#ord}. */
protected int ordBase;
/** Used while uninverting. */
protected PostingsEnum postingsEnum;
/** If true, check and throw an exception if the field has docValues enabled.
* Normally, docValues should be used in preference to DocTermOrds. */
protected boolean checkForDocValues = true;
/** Returns total bytes used. */
public long ramBytesUsed() {
// can cache the mem size since it shouldn't change
if (memsz!=0) return memsz;
long sz = 8*8 + 32; // local fields
if (index != null) sz += index.length * 4;
if (tnums!=null) {
for (byte[] arr : tnums)
if (arr != null) sz += arr.length;
}
memsz = sz;
return sz;
}
/** Inverts all terms */
public DocTermOrds(LeafReader reader, Bits liveDocs, String field) throws IOException {
this(reader, liveDocs, field, null, Integer.MAX_VALUE);
}
// TODO: instead of all these ctors and options, take termsenum!
/** Inverts only terms starting w/ prefix */
public DocTermOrds(LeafReader reader, Bits liveDocs, String field, BytesRef termPrefix) throws IOException {
this(reader, liveDocs, field, termPrefix, Integer.MAX_VALUE);
}
/** Inverts only terms starting w/ prefix, and only terms
* whose docFreq (not taking deletions into account) is
* <= maxTermDocFreq */
public DocTermOrds(LeafReader reader, Bits liveDocs, String field, BytesRef termPrefix, int maxTermDocFreq) throws IOException {
this(reader, liveDocs, field, termPrefix, maxTermDocFreq, DEFAULT_INDEX_INTERVAL_BITS);
}
/** Inverts only terms starting w/ prefix, and only terms
* whose docFreq (not taking deletions into account) is
* <= maxTermDocFreq, with a custom indexing interval
* (default is every 128nd term). */
public DocTermOrds(LeafReader reader, Bits liveDocs, String field, BytesRef termPrefix, int maxTermDocFreq, int indexIntervalBits) throws IOException {
this(field, maxTermDocFreq, indexIntervalBits);
uninvert(reader, liveDocs, termPrefix);
}
/** Subclass inits w/ this, but be sure you then call
* uninvert, only once */
protected DocTermOrds(String field, int maxTermDocFreq, int indexIntervalBits) {
//System.out.println("DTO init field=" + field + " maxTDFreq=" + maxTermDocFreq);
this.field = field;
this.maxTermDocFreq = maxTermDocFreq;
this.indexIntervalBits = indexIntervalBits;
indexIntervalMask = 0xffffffff >>> (32-indexIntervalBits);
indexInterval = 1 << indexIntervalBits;
}
/**
* Returns a TermsEnum that implements ord, or null if no terms in field.
* <p>
* we build a "private" terms
* index internally (WARNING: consumes RAM) and use that
* index to implement ord. This also enables ord on top
* of a composite reader. The returned TermsEnum is
* unpositioned. This returns null if there are no terms.
* </p>
* <p><b>NOTE</b>: you must pass the same reader that was
* used when creating this class
*/
public TermsEnum getOrdTermsEnum(LeafReader reader) throws IOException {
// NOTE: see LUCENE-6529 before attempting to optimize this method to
// return a TermsEnum directly from the reader if it already supports ord().
assert null != indexedTermsArray;
if (0 == indexedTermsArray.length) {
return null;
} else {
return new OrdWrappedTermsEnum(reader);
}
}
/**
* Returns the number of terms in this field
*/
public int numTerms() {
return numTermsInField;
}
/**
* Returns {@code true} if no terms were indexed.
*/
public boolean isEmpty() {
return index == null;
}
/** Subclass can override this */
protected void visitTerm(TermsEnum te, int termNum) throws IOException {
}
/** Invoked during {@link #uninvert(org.apache.lucene.index.LeafReader,Bits,BytesRef)}
* to record the document frequency for each uninverted
* term. */
protected void setActualDocFreq(int termNum, int df) throws IOException {
}
/** Call this only once (if you subclass!) */
protected void uninvert(final LeafReader reader, Bits liveDocs, final BytesRef termPrefix) throws IOException {
final FieldInfo info = reader.getFieldInfos().fieldInfo(field);
if (checkForDocValues && info != null && info.getDocValuesType() != DocValuesType.NONE) {
throw new IllegalStateException("Type mismatch: " + field + " was indexed as " + info.getDocValuesType());
}
//System.out.println("DTO uninvert field=" + field + " prefix=" + termPrefix);
final long startTime = System.nanoTime();
prefix = termPrefix == null ? null : BytesRef.deepCopyOf(termPrefix);
final int maxDoc = reader.maxDoc();
final int[] index = new int[maxDoc]; // immediate term numbers, or the index into the byte[] representing the last number
final int[] lastTerm = new int[maxDoc]; // last term we saw for this document
final byte[][] bytes = new byte[maxDoc][]; // list of term numbers for the doc (delta encoded vInts)
final Terms terms = reader.terms(field);
if (terms == null) {
// No terms
return;
}
final TermsEnum te = terms.iterator();
final BytesRef seekStart = termPrefix != null ? termPrefix : new BytesRef();
//System.out.println("seekStart=" + seekStart.utf8ToString());
if (te.seekCeil(seekStart) == TermsEnum.SeekStatus.END) {
// No terms match
return;
}
// For our "term index wrapper"
final List<BytesRef> indexedTerms = new ArrayList<>();
final PagedBytes indexedTermsBytes = new PagedBytes(15);
// we need a minimum of 9 bytes, but round up to 12 since the space would
// be wasted with most allocators anyway.
byte[] tempArr = new byte[12];
//
// enumerate all terms, and build an intermediate form of the un-inverted field.
//
// During this intermediate form, every document has a (potential) byte[]
// and the int[maxDoc()] array either contains the termNumber list directly
// or the *end* offset of the termNumber list in its byte array (for faster
// appending and faster creation of the final form).
//
// idea... if things are too large while building, we could do a range of docs
// at a time (but it would be a fair amount slower to build)
// could also do ranges in parallel to take advantage of multiple CPUs
// OPTIONAL: remap the largest df terms to the lowest 128 (single byte)
// values. This requires going over the field first to find the most
// frequent terms ahead of time.
int termNum = 0;
postingsEnum = null;
// Loop begins with te positioned to first term (we call
// seek above):
for (;;) {
final BytesRef t = te.term();
if (t == null || (termPrefix != null && !StringHelper.startsWith(t, termPrefix))) {
break;
}
//System.out.println("visit term=" + t.utf8ToString() + " " + t + " termNum=" + termNum);
visitTerm(te, termNum);
if ((termNum & indexIntervalMask) == 0) {
// Index this term
sizeOfIndexedStrings += t.length;
BytesRef indexedTerm = new BytesRef();
indexedTermsBytes.copy(t, indexedTerm);
// TODO: really should 1) strip off useless suffix,
// and 2) use FST not array/PagedBytes
indexedTerms.add(indexedTerm);
}
final int df = te.docFreq();
if (df <= maxTermDocFreq) {
postingsEnum = te.postings(postingsEnum, PostingsEnum.NONE);
// dF, but takes deletions into account
int actualDF = 0;
for (;;) {
int doc = postingsEnum.nextDoc();
if (doc == DocIdSetIterator.NO_MORE_DOCS) {
break;
}
//System.out.println(" chunk=" + chunk + " docs");
actualDF ++;
termInstances++;
//System.out.println(" docID=" + doc);
// add TNUM_OFFSET to the term number to make room for special reserved values:
// 0 (end term) and 1 (index into byte array follows)
int delta = termNum - lastTerm[doc] + TNUM_OFFSET;
lastTerm[doc] = termNum;
int val = index[doc];
if ((val & 0xff)==1) {
// index into byte array (actually the end of
// the doc-specific byte[] when building)
int pos = val >>> 8;
int ilen = vIntSize(delta);
byte[] arr = bytes[doc];
int newend = pos+ilen;
if (newend > arr.length) {
// We avoid a doubling strategy to lower memory usage.
// this faceting method isn't for docs with many terms.
// In hotspot, objects have 2 words of overhead, then fields, rounded up to a 64-bit boundary.
// TODO: figure out what array lengths we can round up to w/o actually using more memory
// (how much space does a byte[] take up? Is data preceded by a 32 bit length only?
// It should be safe to round up to the nearest 32 bits in any case.
int newLen = (newend + 3) & 0xfffffffc; // 4 byte alignment
byte[] newarr = new byte[newLen];
System.arraycopy(arr, 0, newarr, 0, pos);
arr = newarr;
bytes[doc] = newarr;
}
pos = writeInt(delta, arr, pos);
index[doc] = (pos<<8) | 1; // update pointer to end index in byte[]
} else {
// OK, this int has data in it... find the end (a zero starting byte - not
// part of another number, hence not following a byte with the high bit set).
int ipos;
if (val==0) {
ipos=0;
} else if ((val & 0x0000ff80)==0) {
ipos=1;
} else if ((val & 0x00ff8000)==0) {
ipos=2;
} else if ((val & 0xff800000)==0) {
ipos=3;
} else {
ipos=4;
}
//System.out.println(" ipos=" + ipos);
int endPos = writeInt(delta, tempArr, ipos);
//System.out.println(" endpos=" + endPos);
if (endPos <= 4) {
//System.out.println(" fits!");
// value will fit in the integer... move bytes back
for (int j=ipos; j<endPos; j++) {
val |= (tempArr[j] & 0xff) << (j<<3);
}
index[doc] = val;
} else {
// value won't fit... move integer into byte[]
for (int j=0; j<ipos; j++) {
tempArr[j] = (byte)val;
val >>>=8;
}
// point at the end index in the byte[]
index[doc] = (endPos<<8) | 1;
bytes[doc] = tempArr;
tempArr = new byte[12];
}
}
}
setActualDocFreq(termNum, actualDF);
}
termNum++;
if (te.next() == null) {
break;
}
}
numTermsInField = termNum;
long midPoint = System.nanoTime();
if (termInstances == 0) {
// we didn't invert anything
// lower memory consumption.
tnums = null;
} else {
this.index = index;
//
// transform intermediate form into the final form, building a single byte[]
// at a time, and releasing the intermediate byte[]s as we go to avoid
// increasing the memory footprint.
//
for (int pass = 0; pass<256; pass++) {
byte[] target = tnums[pass];
int pos=0; // end in target;
if (target != null) {
pos = target.length;
} else {
target = new byte[4096];
}
// loop over documents, 0x00ppxxxx, 0x01ppxxxx, 0x02ppxxxx
// where pp is the pass (which array we are building), and xx is all values.
// each pass shares the same byte[] for termNumber lists.
for (int docbase = pass<<16; docbase<maxDoc; docbase+=(1<<24)) {
int lim = Math.min(docbase + (1<<16), maxDoc);
for (int doc=docbase; doc<lim; doc++) {
//System.out.println(" pass=" + pass + " process docID=" + doc);
int val = index[doc];
if ((val&0xff) == 1) {
int len = val >>> 8;
//System.out.println(" ptr pos=" + pos);
index[doc] = (pos<<8)|1; // change index to point to start of array
if ((pos & 0xff000000) != 0) {
// we only have 24 bits for the array index
throw new IllegalStateException("Too many values for UnInvertedField faceting on field "+field);
}
byte[] arr = bytes[doc];
/*
for(byte b : arr) {
//System.out.println(" b=" + Integer.toHexString((int) b));
}
*/
bytes[doc] = null; // IMPORTANT: allow GC to avoid OOM
if (target.length <= pos + len) {
int newlen = target.length;
/*** we don't have to worry about the array getting too large
* since the "pos" param will overflow first (only 24 bits available)
if ((newlen<<1) <= 0) {
// overflow...
newlen = Integer.MAX_VALUE;
if (newlen <= pos + len) {
throw new SolrException(400,"Too many terms to uninvert field!");
}
} else {
while (newlen <= pos + len) newlen<<=1; // doubling strategy
}
****/
while (newlen <= pos + len) newlen<<=1; // doubling strategy
byte[] newtarget = new byte[newlen];
System.arraycopy(target, 0, newtarget, 0, pos);
target = newtarget;
}
System.arraycopy(arr, 0, target, pos, len);
pos += len + 1; // skip single byte at end and leave it 0 for terminator
}
}
}
// shrink array
if (pos < target.length) {
byte[] newtarget = new byte[pos];
System.arraycopy(target, 0, newtarget, 0, pos);
target = newtarget;
}
tnums[pass] = target;
if ((pass << 16) > maxDoc)
break;
}
}
indexedTermsArray = indexedTerms.toArray(new BytesRef[indexedTerms.size()]);
long endTime = System.nanoTime();
total_time = (int) TimeUnit.MILLISECONDS.convert(endTime-startTime, TimeUnit.NANOSECONDS);
phase1_time = (int) TimeUnit.MILLISECONDS.convert(midPoint-startTime, TimeUnit.NANOSECONDS);
}
/** Number of bytes to represent an unsigned int as a vint. */
private static int vIntSize(int x) {
if ((x & (0xffffffff << (7*1))) == 0 ) {
return 1;
}
if ((x & (0xffffffff << (7*2))) == 0 ) {
return 2;
}
if ((x & (0xffffffff << (7*3))) == 0 ) {
return 3;
}
if ((x & (0xffffffff << (7*4))) == 0 ) {
return 4;
}
return 5;
}
// todo: if we know the size of the vInt already, we could do
// a single switch on the size
private static int writeInt(int x, byte[] arr, int pos) {
int a;
a = (x >>> (7*4));
if (a != 0) {
arr[pos++] = (byte)(a | 0x80);
}
a = (x >>> (7*3));
if (a != 0) {
arr[pos++] = (byte)(a | 0x80);
}
a = (x >>> (7*2));
if (a != 0) {
arr[pos++] = (byte)(a | 0x80);
}
a = (x >>> (7*1));
if (a != 0) {
arr[pos++] = (byte)(a | 0x80);
}
arr[pos++] = (byte)(x & 0x7f);
return pos;
}
/**
* "wrap" our own terms index around the original IndexReader.
* Only valid if there are terms for this field rom the original reader
*/
private final class OrdWrappedTermsEnum extends TermsEnum {
private final TermsEnum termsEnum;
private BytesRef term;
private long ord = -indexInterval-1; // force "real" seek
public OrdWrappedTermsEnum(LeafReader reader) throws IOException {
assert indexedTermsArray != null;
assert 0 != indexedTermsArray.length;
termsEnum = reader.fields().terms(field).iterator();
}
@Override
public PostingsEnum postings(PostingsEnum reuse, int flags) throws IOException {
return termsEnum.postings(reuse, flags);
}
@Override
public BytesRef term() {
return term;
}
@Override
public BytesRef next() throws IOException {
if (++ord < 0) {
ord = 0;
}
if (termsEnum.next() == null) {
term = null;
return null;
}
return setTerm(); // this is extra work if we know we are in bounds...
}
@Override
public int docFreq() throws IOException {
return termsEnum.docFreq();
}
@Override
public long totalTermFreq() throws IOException {
return termsEnum.totalTermFreq();
}
@Override
public long ord() {
return ordBase + ord;
}
@Override
public SeekStatus seekCeil(BytesRef target) throws IOException {
// already here
if (term != null && term.equals(target)) {
return SeekStatus.FOUND;
}
int startIdx = Arrays.binarySearch(indexedTermsArray, target);
if (startIdx >= 0) {
// we hit the term exactly... lucky us!
TermsEnum.SeekStatus seekStatus = termsEnum.seekCeil(target);
assert seekStatus == TermsEnum.SeekStatus.FOUND;
ord = startIdx << indexIntervalBits;
setTerm();
assert term != null;
return SeekStatus.FOUND;
}
// we didn't hit the term exactly
startIdx = -startIdx-1;
if (startIdx == 0) {
// our target occurs *before* the first term
TermsEnum.SeekStatus seekStatus = termsEnum.seekCeil(target);
assert seekStatus == TermsEnum.SeekStatus.NOT_FOUND;
ord = 0;
setTerm();
assert term != null;
return SeekStatus.NOT_FOUND;
}
// back up to the start of the block
startIdx--;
if ((ord >> indexIntervalBits) == startIdx && term != null && term.compareTo(target) <= 0) {
// we are already in the right block and the current term is before the term we want,
// so we don't need to seek.
} else {
// seek to the right block
TermsEnum.SeekStatus seekStatus = termsEnum.seekCeil(indexedTermsArray[startIdx]);
assert seekStatus == TermsEnum.SeekStatus.FOUND;
ord = startIdx << indexIntervalBits;
setTerm();
assert term != null; // should be non-null since it's in the index
}
while (term != null && term.compareTo(target) < 0) {
next();
}
if (term == null) {
return SeekStatus.END;
} else if (term.compareTo(target) == 0) {
return SeekStatus.FOUND;
} else {
return SeekStatus.NOT_FOUND;
}
}
@Override
public void seekExact(long targetOrd) throws IOException {
int delta = (int) (targetOrd - ordBase - ord);
//System.out.println(" seek(ord) targetOrd=" + targetOrd + " delta=" + delta + " ord=" + ord + " ii=" + indexInterval);
if (delta < 0 || delta > indexInterval) {
final int idx = (int) (targetOrd >>> indexIntervalBits);
final BytesRef base = indexedTermsArray[idx];
//System.out.println(" do seek term=" + base.utf8ToString());
ord = idx << indexIntervalBits;
delta = (int) (targetOrd - ord);
final TermsEnum.SeekStatus seekStatus = termsEnum.seekCeil(base);
assert seekStatus == TermsEnum.SeekStatus.FOUND;
} else {
//System.out.println("seek w/in block");
}
while (--delta >= 0) {
BytesRef br = termsEnum.next();
if (br == null) {
assert false;
return;
}
ord++;
}
setTerm();
assert term != null;
}
private BytesRef setTerm() throws IOException {
term = termsEnum.term();
//System.out.println(" setTerm() term=" + term.utf8ToString() + " vs prefix=" + (prefix == null ? "null" : prefix.utf8ToString()));
if (prefix != null && !StringHelper.startsWith(term, prefix)) {
term = null;
}
return term;
}
}
/** Returns the term ({@link BytesRef}) corresponding to
* the provided ordinal. */
public BytesRef lookupTerm(TermsEnum termsEnum, int ord) throws IOException {
termsEnum.seekExact(ord);
return termsEnum.term();
}
/** Returns a SortedSetDocValues view of this instance */
public SortedSetDocValues iterator(LeafReader reader) throws IOException {
if (isEmpty()) {
return DocValues.emptySortedSet();
} else {
return new LegacySortedSetDocValuesWrapper(new Iterator(reader), reader.maxDoc());
}
}
private class Iterator extends LegacySortedSetDocValues {
final LeafReader reader;
final TermsEnum te; // used internally for lookupOrd() and lookupTerm()
// currently we read 5 at a time (using the logic of the old iterator)
final int buffer[] = new int[5];
int bufferUpto;
int bufferLength;
private int tnum;
private int upto;
private byte[] arr;
Iterator(LeafReader reader) throws IOException {
this.reader = reader;
this.te = termsEnum();
}
@Override
public long nextOrd() {
while (bufferUpto == bufferLength) {
if (bufferLength < buffer.length) {
return NO_MORE_ORDS;
} else {
bufferLength = read(buffer);
bufferUpto = 0;
}
}
return buffer[bufferUpto++];
}
/** Buffer must be at least 5 ints long. Returns number
* of term ords placed into buffer; if this count is
* less than buffer.length then that is the end. */
int read(int[] buffer) {
int bufferUpto = 0;
if (arr == null) {
// code is inlined into upto
//System.out.println("inlined");
int code = upto;
int delta = 0;
for (;;) {
delta = (delta << 7) | (code & 0x7f);
if ((code & 0x80)==0) {
if (delta==0) break;
tnum += delta - TNUM_OFFSET;
buffer[bufferUpto++] = ordBase+tnum;
//System.out.println(" tnum=" + tnum);
delta = 0;
}
code >>>= 8;
}
} else {
// code is a pointer
for(;;) {
int delta = 0;
for(;;) {
byte b = arr[upto++];
delta = (delta << 7) | (b & 0x7f);
//System.out.println(" cycle: upto=" + upto + " delta=" + delta + " b=" + b);
if ((b & 0x80) == 0) break;
}
//System.out.println(" delta=" + delta);
if (delta == 0) break;
tnum += delta - TNUM_OFFSET;
//System.out.println(" tnum=" + tnum);
buffer[bufferUpto++] = ordBase+tnum;
if (bufferUpto == buffer.length) {
break;
}
}
}
return bufferUpto;
}
@Override
public void setDocument(int docID) {
tnum = 0;
final int code = index[docID];
if ((code & 0xff)==1) {
// a pointer
upto = code>>>8;
//System.out.println(" pointer! upto=" + upto);
int whichArray = (docID >>> 16) & 0xff;
arr = tnums[whichArray];
} else {
//System.out.println(" inline!");
arr = null;
upto = code;
}
bufferUpto = 0;
bufferLength = read(buffer);
}
@Override
public BytesRef lookupOrd(long ord) {
try {
return DocTermOrds.this.lookupTerm(te, (int) ord);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public long getValueCount() {
return numTerms();
}
@Override
public long lookupTerm(BytesRef key) {
try {
switch (te.seekCeil(key)) {
case FOUND:
assert te.ord() >= 0;
return te.ord();
case NOT_FOUND:
assert te.ord() >= 0;
return -te.ord()-1;
default: /* END */
return -numTerms()-1;
}
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public TermsEnum termsEnum() {
try {
return getOrdTermsEnum(reader);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}
}