/*
* 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.axis2.transport.nhttp;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.HttpHost;
import org.apache.http.nio.NHttpClientConnection;
import org.apache.http.protocol.ExecutionContext;
import java.io.IOException;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
public class ConnectionPool {
private static final Log log = LogFactory.getLog(ConnectionPool.class);
/** A map of available connections for reuse. The key selects the host+port of the
* connection and the value contains a List of available connections to destination
*/
private static Map connMap = Collections.synchronizedMap(new HashMap());
public static NHttpClientConnection getConnection(String host, int port) {
String key = host + ":" + Integer.toString(port);
List connections = (List) connMap.get(key);
if (connections == null || connections.isEmpty()) {
if (log.isDebugEnabled()) {
log.debug("No connections available for reuse");
}
return null;
} else {
NHttpClientConnection conn = null;
synchronized (connections) {
while (!connections.isEmpty()) {
conn = (NHttpClientConnection) connections.remove(0);
if (conn.isOpen()) {
if (log.isDebugEnabled()) {
log.debug("A connection to host : " + host + " on port : " +
port + " is available in the pool, and will be reused");
}
return conn;
} else {
if (log.isDebugEnabled()) {
log.debug("closing stale connection");
}
try {
conn.close();
} catch (IOException ignore) {
}
}
}
}
return null;
}
}
public static void release(NHttpClientConnection conn) {
HttpHost host = (HttpHost) conn.getContext().getAttribute(
ExecutionContext.HTTP_TARGET_HOST);
String key = host.getHostName() + ":" + Integer.toString(host.getPort());
List connections = (List) connMap.get(key);
if (connections == null) {
synchronized(connMap) {
// use double locking to make sure
connections = (List) connMap.get(key);
if (connections == null) {
connections = Collections.synchronizedList(new LinkedList());
connMap.put(key, connections);
}
}
}
connections.add(conn);
log.debug("Released a connection to host: " + host.getHostName() + " on port : " +
host.getPort() + " to the connection pool of current size : " + connections.size());
}
}