/*
* 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.wicket.threadtest.apps.app2;
import java.util.ArrayDeque;
import java.util.Deque;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Test pool.
*
* @author eelcohillenius
*/
public class Pool
{
private static Pool _instance = new Pool();
private static final Logger log = LoggerFactory.getLogger(Pool.class);
/**
* @return the connection
*/
public static Connection getConnection()
{
return getInstance().doGetConnection();
}
/**
* @return the {@link Pool} instance
*/
public static Pool getInstance()
{
return _instance;
}
/**
* Releases the pool
*/
public static void release()
{
getInstance().doRelease();
}
private final Connection[] allConnections;
private final Deque<Connection> available = new ArrayDeque<Connection>();
private final ThreadLocal<Connection> locks = new ThreadLocal<Connection>();
private final int size = 3;
private Pool()
{
allConnections = new Connection[size];
for (int i = 0; i < size; i++)
{
Connection connection = new Connection(String.valueOf(i));
allConnections[i] = connection;
available.push(connection);
}
}
private synchronized Connection doGetConnection()
{
Connection c = locks.get();
if (c != null)
{
return c;
}
else
{
while (c == null)
{
if (!available.isEmpty())
{
c = available.pop();
locks.set(c);
log.info("returning " + c + " for " + Thread.currentThread());
}
else
{
try
{
log.info("enter wait for " + Thread.currentThread());
wait();
}
catch (InterruptedException e)
{
throw new RuntimeException(e);
}
}
}
}
return c;
}
private synchronized void doRelease()
{
Connection c = locks.get();
if (c != null)
{
available.push(c);
locks.remove();
log.info("releasing " + c + " for " + Thread.currentThread());
notifyAll();
}
}
}