/**
* 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.activemq.store.kahadb.plist;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.activemq.management.SizeStatisticImpl;
import org.apache.activemq.store.PList;
import org.apache.activemq.store.PListEntry;
import org.apache.activemq.store.kahadb.disk.index.ListIndex;
import org.apache.activemq.store.kahadb.disk.index.ListNode;
import org.apache.activemq.store.kahadb.disk.journal.Location;
import org.apache.activemq.store.kahadb.disk.page.Transaction;
import org.apache.activemq.store.kahadb.disk.util.LocationMarshaller;
import org.apache.activemq.store.kahadb.disk.util.StringMarshaller;
import org.apache.activemq.util.ByteSequence;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class PListImpl extends ListIndex<String, Location> implements PList {
static final Logger LOG = LoggerFactory.getLogger(PListImpl.class);
final PListStoreImpl store;
private String name;
Object indexLock;
private final SizeStatisticImpl messageSize;
PListImpl(PListStoreImpl store) {
this.store = store;
this.indexLock = store.getIndexLock();
setPageFile(store.getPageFile());
setKeyMarshaller(StringMarshaller.INSTANCE);
setValueMarshaller(LocationMarshaller.INSTANCE);
messageSize = new SizeStatisticImpl("messageSize", "The size in bytes of the pending messages");
messageSize.setEnabled(true);
}
public void setName(String name) {
this.name = name;
}
@Override
public String getName() {
return this.name;
}
void read(DataInput in) throws IOException {
setHeadPageId(in.readLong());
}
public void write(DataOutput out) throws IOException {
out.writeLong(getHeadPageId());
}
@Override
public synchronized void destroy() throws IOException {
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
clear(tx);
unload(tx);
}
});
}
}
class Locator {
final String id;
Locator(String id) {
this.id = id;
}
PListImpl plist() {
return PListImpl.this;
}
}
@Override
public Object addLast(final String id, final ByteSequence bs) throws IOException {
final Location location = this.store.write(bs, false);
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
add(tx, id, location);
}
});
}
return new Locator(id);
}
@Override
public Object addFirst(final String id, final ByteSequence bs) throws IOException {
final Location location = this.store.write(bs, false);
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
addFirst(tx, id, location);
}
});
}
return new Locator(id);
}
@Override
public boolean remove(final Object l) throws IOException {
Locator locator = (Locator) l;
assert locator!=null;
assert locator.plist()==this;
return remove(locator.id);
}
public boolean remove(final String id) throws IOException {
final AtomicBoolean result = new AtomicBoolean();
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
result.set(remove(tx, id) != null);
}
});
}
return result.get();
}
public boolean remove(final long position) throws IOException {
final AtomicBoolean result = new AtomicBoolean();
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
Iterator<Map.Entry<String, Location>> iterator = iterator(tx, position);
if (iterator.hasNext()) {
iterator.next();
iterator.remove();
result.set(true);
} else {
result.set(false);
}
}
});
}
return result.get();
}
public PListEntry get(final long position) throws IOException {
PListEntry result = null;
final AtomicReference<Map.Entry<String, Location>> ref = new AtomicReference<Map.Entry<String, Location>>();
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
Iterator<Map.Entry<String, Location>> iterator = iterator(tx, position);
ref.set(iterator.next());
}
});
}
if (ref.get() != null) {
ByteSequence bs = this.store.getPayload(ref.get().getValue());
result = new PListEntry(ref.get().getKey(), bs, new Locator(ref.get().getKey()));
}
return result;
}
public PListEntry getFirst() throws IOException {
PListEntry result = null;
final AtomicReference<Map.Entry<String, Location>> ref = new AtomicReference<Map.Entry<String, Location>>();
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
ref.set(getFirst(tx));
}
});
}
if (ref.get() != null) {
ByteSequence bs = this.store.getPayload(ref.get().getValue());
result = new PListEntry(ref.get().getKey(), bs, new Locator(ref.get().getKey()));
}
return result;
}
public PListEntry getLast() throws IOException {
PListEntry result = null;
final AtomicReference<Map.Entry<String, Location>> ref = new AtomicReference<Map.Entry<String, Location>>();
synchronized (indexLock) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
ref.set(getLast(tx));
}
});
}
if (ref.get() != null) {
ByteSequence bs = this.store.getPayload(ref.get().getValue());
result = new PListEntry(ref.get().getKey(), bs, new Locator(ref.get().getKey()));
}
return result;
}
@Override
public boolean isEmpty() {
return size() == 0;
}
@Override
public PListIterator iterator() throws IOException {
return new PListIteratorImpl();
}
final class PListIteratorImpl implements PListIterator {
final Iterator<Map.Entry<String, Location>> iterator;
final Transaction tx;
PListIteratorImpl() throws IOException {
tx = store.pageFile.tx();
synchronized (indexLock) {
this.iterator = iterator(tx);
}
}
@Override
public boolean hasNext() {
return iterator.hasNext();
}
@Override
public PListEntry next() {
Map.Entry<String, Location> entry = iterator.next();
ByteSequence bs = null;
try {
bs = store.getPayload(entry.getValue());
} catch (IOException unexpected) {
NoSuchElementException e = new NoSuchElementException(unexpected.getLocalizedMessage());
e.initCause(unexpected);
throw e;
}
return new PListEntry(entry.getKey(), bs, new Locator(entry.getKey()));
}
@Override
public void remove() {
try {
synchronized (indexLock) {
tx.execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
iterator.remove();
}
});
}
} catch (IOException unexpected) {
IllegalStateException e = new IllegalStateException(unexpected);
e.initCause(unexpected);
throw e;
}
}
@Override
public void release() {
try {
tx.rollback();
} catch (IOException unexpected) {
IllegalStateException e = new IllegalStateException(unexpected);
e.initCause(unexpected);
throw e;
}
}
}
public void claimFileLocations(final Set<Integer> candidates) throws IOException {
synchronized (indexLock) {
if (loaded.get()) {
this.store.getPageFile().tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
Iterator<Map.Entry<String,Location>> iterator = iterator(tx);
while (iterator.hasNext()) {
Location location = iterator.next().getValue();
candidates.remove(location.getDataFileId());
}
}
});
}
}
}
@Override
public long messageSize() {
return messageSize.getTotalSize();
}
@Override
public synchronized Location add(Transaction tx, String key, Location value)
throws IOException {
Location location = super.add(tx, key, value);
messageSize.addSize(value.getSize());
return location;
}
@Override
public synchronized Location addFirst(Transaction tx, String key,
Location value) throws IOException {
Location location = super.addFirst(tx, key, value);
messageSize.addSize(value.getSize());
return location;
}
@Override
public synchronized void clear(Transaction tx) throws IOException {
messageSize.reset();
super.clear(tx);
}
@Override
protected synchronized void onLoad(ListNode<String, Location> node, Transaction tx) {
try {
Iterator<Entry<String, Location>> i = node.iterator(tx);
while (i.hasNext()) {
messageSize.addSize(i.next().getValue().getSize());
}
} catch (IOException e) {
LOG.warn("could not increment message size", e);
}
}
@Override
public void onRemove(Entry<String, Location> removed) {
super.onRemove(removed);
if (removed != null) {
messageSize.addSize(-removed.getValue().getSize());
}
}
@Override
public String toString() {
return name + "[headPageId=" + getHeadPageId() + ",tailPageId=" + getTailPageId() + ", size=" + size() + "]";
}
}