| // |
| // ======================================================================== |
| // Copyright (c) 1995-2017 Mort Bay Consulting Pty. Ltd. |
| // ------------------------------------------------------------------------ |
| // All rights reserved. This program and the accompanying materials |
| // are made available under the terms of the Eclipse Public License v1.0 |
| // and Apache License v2.0 which accompanies this distribution. |
| // |
| // The Eclipse Public License is available at |
| // http://www.eclipse.org/legal/epl-v10.html |
| // |
| // The Apache License v2.0 is available at |
| // http://www.opensource.org/licenses/apache2.0.php |
| // |
| // You may elect to redistribute this code under either of these licenses. |
| // ======================================================================== |
| // |
| |
| package org.eclipse.jetty.client; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.Deque; |
| import java.util.List; |
| import java.util.Queue; |
| import java.util.concurrent.LinkedBlockingDeque; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import java.util.concurrent.locks.ReentrantLock; |
| |
| import org.eclipse.jetty.client.api.Connection; |
| import org.eclipse.jetty.client.api.Destination; |
| import org.eclipse.jetty.util.BlockingArrayQueue; |
| import org.eclipse.jetty.util.Callback; |
| import org.eclipse.jetty.util.Promise; |
| import org.eclipse.jetty.util.annotation.ManagedAttribute; |
| import org.eclipse.jetty.util.annotation.ManagedObject; |
| import org.eclipse.jetty.util.component.ContainerLifeCycle; |
| import org.eclipse.jetty.util.component.Dumpable; |
| import org.eclipse.jetty.util.log.Log; |
| import org.eclipse.jetty.util.log.Logger; |
| import org.eclipse.jetty.util.thread.Sweeper; |
| |
| @ManagedObject("The connection pool") |
| public class DuplexConnectionPool implements Closeable, Dumpable, Sweeper.Sweepable |
| { |
| private static final Logger LOG = Log.getLogger(DuplexConnectionPool.class); |
| |
| private final AtomicInteger connectionCount = new AtomicInteger(); |
| private final ReentrantLock lock = new ReentrantLock(); |
| private final Destination destination; |
| private final int maxConnections; |
| private final Callback requester; |
| private final Deque<Connection> idleConnections; |
| private final Queue<Connection> activeConnections; |
| |
| public DuplexConnectionPool(Destination destination, int maxConnections, Callback requester) |
| { |
| this.destination = destination; |
| this.maxConnections = maxConnections; |
| this.requester = requester; |
| this.idleConnections = new LinkedBlockingDeque<>(maxConnections); |
| this.activeConnections = new BlockingArrayQueue<>(maxConnections); |
| } |
| |
| @ManagedAttribute(value = "The number of connections", readonly = true) |
| public int getConnectionCount() |
| { |
| return connectionCount.get(); |
| } |
| |
| @ManagedAttribute(value = "The number of idle connections", readonly = true) |
| public int getIdleConnectionCount() |
| { |
| lock(); |
| try |
| { |
| return idleConnections.size(); |
| } |
| finally |
| { |
| unlock(); |
| } |
| } |
| |
| @ManagedAttribute(value = "The number of active connections", readonly = true) |
| public int getActiveConnectionCount() |
| { |
| lock(); |
| try |
| { |
| return activeConnections.size(); |
| } |
| finally |
| { |
| unlock(); |
| } |
| } |
| |
| public Queue<Connection> getIdleConnections() |
| { |
| return idleConnections; |
| } |
| |
| public Queue<Connection> getActiveConnections() |
| { |
| return activeConnections; |
| } |
| |
| public Connection acquire() |
| { |
| Connection connection = activateIdle(); |
| if (connection == null) |
| connection = tryCreate(); |
| return connection; |
| } |
| |
| private Connection tryCreate() |
| { |
| while (true) |
| { |
| int current = getConnectionCount(); |
| final int next = current + 1; |
| |
| if (next > maxConnections) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Max connections {}/{} reached", current, maxConnections); |
| // Try again the idle connections |
| return activateIdle(); |
| } |
| |
| if (connectionCount.compareAndSet(current, next)) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection {}/{} creation", next, maxConnections); |
| |
| destination.newConnection(new Promise<Connection>() |
| { |
| @Override |
| public void succeeded(Connection connection) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection {}/{} creation succeeded {}", next, maxConnections, connection); |
| |
| idleCreated(connection); |
| |
| proceed(); |
| } |
| |
| @Override |
| public void failed(Throwable x) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection " + next + "/" + maxConnections + " creation failed", x); |
| |
| connectionCount.decrementAndGet(); |
| |
| requester.failed(x); |
| } |
| }); |
| |
| // Try again the idle connections |
| return activateIdle(); |
| } |
| } |
| } |
| |
| protected void proceed() |
| { |
| requester.succeeded(); |
| } |
| |
| protected void idleCreated(Connection connection) |
| { |
| boolean idle; |
| lock(); |
| try |
| { |
| // Use "cold" new connections as last. |
| idle = idleConnections.offerLast(connection); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| idle(connection, idle); |
| } |
| |
| private Connection activateIdle() |
| { |
| boolean acquired; |
| Connection connection; |
| lock(); |
| try |
| { |
| connection = idleConnections.pollFirst(); |
| if (connection == null) |
| return null; |
| acquired = activeConnections.offer(connection); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| if (acquired) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection active {}", connection); |
| acquired(connection); |
| return connection; |
| } |
| else |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection active overflow {}", connection); |
| connection.close(); |
| return null; |
| } |
| } |
| |
| protected void acquired(Connection connection) |
| { |
| } |
| |
| public boolean release(Connection connection) |
| { |
| boolean idle; |
| lock(); |
| try |
| { |
| if (!activeConnections.remove(connection)) |
| return false; |
| // Make sure we use "hot" connections first. |
| idle = offerIdle(connection); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| released(connection); |
| return idle(connection, idle); |
| } |
| |
| protected boolean offerIdle(Connection connection) |
| { |
| return idleConnections.offerFirst(connection); |
| } |
| |
| protected boolean idle(Connection connection, boolean idle) |
| { |
| if (idle) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection idle {}", connection); |
| return true; |
| } |
| else |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection idle overflow {}", connection); |
| connection.close(); |
| return false; |
| } |
| } |
| |
| protected void released(Connection connection) |
| { |
| } |
| |
| public boolean remove(Connection connection) |
| { |
| return remove(connection, false); |
| } |
| |
| protected boolean remove(Connection connection, boolean force) |
| { |
| boolean activeRemoved; |
| boolean idleRemoved; |
| lock(); |
| try |
| { |
| activeRemoved = activeConnections.remove(connection); |
| idleRemoved = idleConnections.remove(connection); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| if (activeRemoved || force) |
| released(connection); |
| boolean removed = activeRemoved || idleRemoved || force; |
| if (removed) |
| { |
| int pooled = connectionCount.decrementAndGet(); |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Connection removed {} - pooled: {}", connection, pooled); |
| } |
| return removed; |
| } |
| |
| public boolean isActive(Connection connection) |
| { |
| lock(); |
| try |
| { |
| return activeConnections.contains(connection); |
| } |
| finally |
| { |
| unlock(); |
| } |
| } |
| |
| public boolean isIdle(Connection connection) |
| { |
| lock(); |
| try |
| { |
| return idleConnections.contains(connection); |
| } |
| finally |
| { |
| unlock(); |
| } |
| } |
| |
| public boolean isEmpty() |
| { |
| return connectionCount.get() == 0; |
| } |
| |
| public void close() |
| { |
| List<Connection> idles = new ArrayList<>(); |
| List<Connection> actives = new ArrayList<>(); |
| lock(); |
| try |
| { |
| idles.addAll(idleConnections); |
| idleConnections.clear(); |
| actives.addAll(activeConnections); |
| activeConnections.clear(); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| connectionCount.set(0); |
| |
| for (Connection connection : idles) |
| connection.close(); |
| |
| // A bit drastic, but we cannot wait for all requests to complete |
| for (Connection connection : actives) |
| connection.close(); |
| } |
| |
| @Override |
| public String dump() |
| { |
| return ContainerLifeCycle.dump(this); |
| } |
| |
| @Override |
| public void dump(Appendable out, String indent) throws IOException |
| { |
| List<Connection> actives = new ArrayList<>(); |
| List<Connection> idles = new ArrayList<>(); |
| lock(); |
| try |
| { |
| actives.addAll(activeConnections); |
| idles.addAll(idleConnections); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| ContainerLifeCycle.dumpObject(out, this); |
| ContainerLifeCycle.dump(out, indent, actives, idles); |
| } |
| |
| @Override |
| public boolean sweep() |
| { |
| List<Connection> toSweep = new ArrayList<>(); |
| lock(); |
| try |
| { |
| for (Connection connection : activeConnections) |
| { |
| if (connection instanceof Sweeper.Sweepable) |
| toSweep.add(connection); |
| } |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| for (Connection connection : toSweep) |
| { |
| if (((Sweeper.Sweepable)connection).sweep()) |
| { |
| boolean removed = remove(connection, true); |
| LOG.warn("Connection swept: {}{}{} from active connections{}{}", |
| connection, |
| System.lineSeparator(), |
| removed ? "Removed" : "Not removed", |
| System.lineSeparator(), |
| dump()); |
| } |
| } |
| |
| return false; |
| } |
| |
| protected void lock() |
| { |
| lock.lock(); |
| } |
| |
| protected void unlock() |
| { |
| lock.unlock(); |
| } |
| |
| @Override |
| public String toString() |
| { |
| int activeSize; |
| int idleSize; |
| lock(); |
| try |
| { |
| activeSize = activeConnections.size(); |
| idleSize = idleConnections.size(); |
| } |
| finally |
| { |
| unlock(); |
| } |
| |
| return String.format("%s[c=%d/%d,a=%d,i=%d]", |
| getClass().getSimpleName(), |
| connectionCount.get(), |
| maxConnections, |
| activeSize, |
| idleSize); |
| } |
| } |