/*
* 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.catalina.tribes.io;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.catalina.tribes.util.StringManager;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
public class BufferPool {
private static final Log log = LogFactory.getLog(BufferPool.class);
public static final int DEFAULT_POOL_SIZE = Integer
.getInteger("org.apache.catalina.tribes.io.BufferPool.DEFAULT_POOL_SIZE", 100 * 1024 * 1024).intValue(); // 100
// MiB
protected static final StringManager sm = StringManager.getManager(BufferPool.class);
protected static volatile BufferPool instance = null;
public static BufferPool getBufferPool() {
if (instance == null) {
synchronized (BufferPool.class) {
if (instance == null) {
BufferPool pool = new BufferPool();
pool.setMaxSize(DEFAULT_POOL_SIZE);
log.info(sm.getString("bufferPool.created", Integer.toString(DEFAULT_POOL_SIZE),
pool.getClass().getName()));
instance = pool;
}
}
}
return instance;
}
private BufferPool() {
}
public XByteBuffer getBuffer(int minSize, boolean discard) {
XByteBuffer buffer = queue.poll();
if (buffer != null) {
size.addAndGet(-buffer.getCapacity());
}
if (buffer == null) {
buffer = new XByteBuffer(minSize, discard);
} else if (buffer.getCapacity() <= minSize) {
buffer.expand(minSize);
}
buffer.setDiscard(discard);
buffer.reset();
return buffer;
}
public void returnBuffer(XByteBuffer buffer) {
if ((size.get() + buffer.getCapacity()) <= maxSize) {
size.addAndGet(buffer.getCapacity());
queue.offer(buffer);
}
}
public void clear() {
queue.clear();
size.set(0);
}
protected int maxSize;
protected final AtomicInteger size = new AtomicInteger(0);
protected final ConcurrentLinkedQueue<XByteBuffer> queue = new ConcurrentLinkedQueue<>();
public void setMaxSize(int bytes) {
this.maxSize = bytes;
}
public int getMaxSize() {
return maxSize;
}
}