org.apache.http.impl.conn.PoolingClientConnectionManager Maven / Gradle / Ivy
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/*
* ====================================================================
* 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* .
*
*/
package org.apache.http.impl.conn;
import java.io.IOException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.annotation.Contract;
import org.apache.http.annotation.ThreadingBehavior;
import org.apache.http.conn.ClientConnectionManager;
import org.apache.http.conn.ClientConnectionOperator;
import org.apache.http.conn.ClientConnectionRequest;
import org.apache.http.conn.ConnectionPoolTimeoutException;
import org.apache.http.conn.DnsResolver;
import org.apache.http.conn.ManagedClientConnection;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.scheme.SchemeRegistry;
import org.apache.http.pool.ConnPoolControl;
import org.apache.http.pool.PoolStats;
import org.apache.http.util.Args;
import org.apache.http.util.Asserts;
/**
* Manages a pool of {@link org.apache.http.conn.OperatedClientConnection}
* and is able to service connection requests from multiple execution threads.
* Connections are pooled on a per route basis. A request for a route which
* already the manager has persistent connections for available in the pool
* will be services by leasing a connection from the pool rather than
* creating a brand new connection.
*
* PoolingConnectionManager maintains a maximum limit of connection on
* a per route basis and in total. Per default this implementation will
* create no more than than 2 concurrent connections per given route
* and no more 20 connections in total. For many real-world applications
* these limits may prove too constraining, especially if they use HTTP
* as a transport protocol for their services. Connection limits, however,
* can be adjusted using HTTP parameters.
*
* @since 4.2
*
* @deprecated (4.3) use {@link PoolingHttpClientConnectionManager}.
*/
@Deprecated
@Contract(threading = ThreadingBehavior.SAFE_CONDITIONAL)
public class PoolingClientConnectionManager implements ClientConnectionManager, ConnPoolControl {
private final Log log = LogFactory.getLog(getClass());
private final SchemeRegistry schemeRegistry;
private final HttpConnPool pool;
private final ClientConnectionOperator operator;
/** the custom-configured DNS lookup mechanism. */
private final DnsResolver dnsResolver;
public PoolingClientConnectionManager(final SchemeRegistry schreg) {
this(schreg, -1, TimeUnit.MILLISECONDS);
}
public PoolingClientConnectionManager(final SchemeRegistry schreg,final DnsResolver dnsResolver) {
this(schreg, -1, TimeUnit.MILLISECONDS,dnsResolver);
}
public PoolingClientConnectionManager() {
this(SchemeRegistryFactory.createDefault());
}
public PoolingClientConnectionManager(
final SchemeRegistry schemeRegistry,
final long timeToLive, final TimeUnit timeUnit) {
this(schemeRegistry, timeToLive, timeUnit, new SystemDefaultDnsResolver());
}
public PoolingClientConnectionManager(final SchemeRegistry schemeRegistry,
final long timeToLive, final TimeUnit timeUnit,
final DnsResolver dnsResolver) {
super();
Args.notNull(schemeRegistry, "Scheme registry");
Args.notNull(dnsResolver, "DNS resolver");
this.schemeRegistry = schemeRegistry;
this.dnsResolver = dnsResolver;
this.operator = createConnectionOperator(schemeRegistry);
this.pool = new HttpConnPool(this.log, this.operator, 2, 20, timeToLive, timeUnit);
}
@Override
protected void finalize() throws Throwable {
try {
shutdown();
} finally {
super.finalize();
}
}
/**
* Hook for creating the connection operator.
* It is called by the constructor.
* Derived classes can override this method to change the
* instantiation of the operator.
* The default implementation here instantiates
* {@link DefaultClientConnectionOperator DefaultClientConnectionOperator}.
*
* @param schreg the scheme registry.
*
* @return the connection operator to use
*/
protected ClientConnectionOperator createConnectionOperator(final SchemeRegistry schreg) {
return new DefaultClientConnectionOperator(schreg, this.dnsResolver);
}
@Override
public SchemeRegistry getSchemeRegistry() {
return this.schemeRegistry;
}
private String format(final HttpRoute route, final Object state) {
final StringBuilder buf = new StringBuilder();
buf.append("[route: ").append(route).append("]");
if (state != null) {
buf.append("[state: ").append(state).append("]");
}
return buf.toString();
}
private String formatStats(final HttpRoute route) {
final StringBuilder buf = new StringBuilder();
final PoolStats totals = this.pool.getTotalStats();
final PoolStats stats = this.pool.getStats(route);
buf.append("[total kept alive: ").append(totals.getAvailable()).append("; ");
buf.append("route allocated: ").append(stats.getLeased() + stats.getAvailable());
buf.append(" of ").append(stats.getMax()).append("; ");
buf.append("total allocated: ").append(totals.getLeased() + totals.getAvailable());
buf.append(" of ").append(totals.getMax()).append("]");
return buf.toString();
}
private String format(final HttpPoolEntry entry) {
final StringBuilder buf = new StringBuilder();
buf.append("[id: ").append(entry.getId()).append("]");
buf.append("[route: ").append(entry.getRoute()).append("]");
final Object state = entry.getState();
if (state != null) {
buf.append("[state: ").append(state).append("]");
}
return buf.toString();
}
@Override
public ClientConnectionRequest requestConnection(
final HttpRoute route,
final Object state) {
Args.notNull(route, "HTTP route");
if (this.log.isDebugEnabled()) {
this.log.debug("Connection request: " + format(route, state) + formatStats(route));
}
final Future future = this.pool.lease(route, state);
return new ClientConnectionRequest() {
@Override
public void abortRequest() {
future.cancel(true);
}
@Override
public ManagedClientConnection getConnection(
final long timeout,
final TimeUnit timeUnit) throws InterruptedException, ConnectionPoolTimeoutException {
return leaseConnection(future, timeout, timeUnit);
}
};
}
ManagedClientConnection leaseConnection(
final Future future,
final long timeout,
final TimeUnit timeUnit) throws InterruptedException, ConnectionPoolTimeoutException {
final HttpPoolEntry entry;
try {
entry = future.get(timeout, timeUnit);
if (entry == null || future.isCancelled()) {
throw new InterruptedException();
}
Asserts.check(entry.getConnection() != null, "Pool entry with no connection");
if (this.log.isDebugEnabled()) {
this.log.debug("Connection leased: " + format(entry) + formatStats(entry.getRoute()));
}
return new ManagedClientConnectionImpl(this, this.operator, entry);
} catch (final ExecutionException ex) {
Throwable cause = ex.getCause();
if (cause == null) {
cause = ex;
}
this.log.error("Unexpected exception leasing connection from pool", cause);
// Should never happen
throw new InterruptedException();
} catch (final TimeoutException ex) {
throw new ConnectionPoolTimeoutException("Timeout waiting for connection from pool");
}
}
@Override
public void releaseConnection(
final ManagedClientConnection conn, final long keepalive, final TimeUnit timeUnit) {
Args.check(conn instanceof ManagedClientConnectionImpl, "Connection class mismatch, " +
"connection not obtained from this manager");
final ManagedClientConnectionImpl managedConn = (ManagedClientConnectionImpl) conn;
Asserts.check(managedConn.getManager() == this, "Connection not obtained from this manager");
synchronized (managedConn) {
final HttpPoolEntry entry = managedConn.detach();
if (entry == null) {
return;
}
try {
if (managedConn.isOpen() && !managedConn.isMarkedReusable()) {
try {
managedConn.shutdown();
} catch (final IOException iox) {
if (this.log.isDebugEnabled()) {
this.log.debug("I/O exception shutting down released connection", iox);
}
}
}
// Only reusable connections can be kept alive
if (managedConn.isMarkedReusable()) {
entry.updateExpiry(keepalive, timeUnit != null ? timeUnit : TimeUnit.MILLISECONDS);
if (this.log.isDebugEnabled()) {
final String s;
if (keepalive > 0) {
s = "for " + keepalive + " " + timeUnit;
} else {
s = "indefinitely";
}
this.log.debug("Connection " + format(entry) + " can be kept alive " + s);
}
}
} finally {
this.pool.release(entry, managedConn.isMarkedReusable());
}
if (this.log.isDebugEnabled()) {
this.log.debug("Connection released: " + format(entry) + formatStats(entry.getRoute()));
}
}
}
@Override
public void shutdown() {
this.log.debug("Connection manager is shutting down");
try {
this.pool.shutdown();
} catch (final IOException ex) {
this.log.debug("I/O exception shutting down connection manager", ex);
}
this.log.debug("Connection manager shut down");
}
@Override
public void closeIdleConnections(final long idleTimeout, final TimeUnit timeUnit) {
if (this.log.isDebugEnabled()) {
this.log.debug("Closing connections idle longer than " + idleTimeout + " " + timeUnit);
}
this.pool.closeIdle(idleTimeout, timeUnit);
}
@Override
public void closeExpiredConnections() {
this.log.debug("Closing expired connections");
this.pool.closeExpired();
}
@Override
public int getMaxTotal() {
return this.pool.getMaxTotal();
}
@Override
public void setMaxTotal(final int max) {
this.pool.setMaxTotal(max);
}
@Override
public int getDefaultMaxPerRoute() {
return this.pool.getDefaultMaxPerRoute();
}
@Override
public void setDefaultMaxPerRoute(final int max) {
this.pool.setDefaultMaxPerRoute(max);
}
@Override
public int getMaxPerRoute(final HttpRoute route) {
return this.pool.getMaxPerRoute(route);
}
@Override
public void setMaxPerRoute(final HttpRoute route, final int max) {
this.pool.setMaxPerRoute(route, max);
}
@Override
public PoolStats getTotalStats() {
return this.pool.getTotalStats();
}
@Override
public PoolStats getStats(final HttpRoute route) {
return this.pool.getStats(route);
}
}