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
*
* 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
*/
@ThreadSafe
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 tunit) {
this(schemeRegistry, timeToLive, tunit, new SystemDefaultDnsResolver());
}
public PoolingClientConnectionManager(final SchemeRegistry schemeRegistry,
final long timeToLive, final TimeUnit tunit,
final DnsResolver dnsResolver) {
super();
if (schemeRegistry == null) {
throw new IllegalArgumentException("Scheme registry may not be null");
}
if (dnsResolver == null) {
throw new IllegalArgumentException("DNS resolver may not be null");
}
this.schemeRegistry = schemeRegistry;
this.dnsResolver = dnsResolver;
this.operator = createConnectionOperator(schemeRegistry);
this.pool = new HttpConnPool(this.log, this.operator, 2, 20, timeToLive, tunit);
}
@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(SchemeRegistry schreg) {
return new DefaultClientConnectionOperator(schreg, this.dnsResolver);
}
public SchemeRegistry getSchemeRegistry() {
return this.schemeRegistry;
}
private String format(final HttpRoute route, final Object state) {
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) {
StringBuilder buf = new StringBuilder();
PoolStats totals = this.pool.getTotalStats();
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) {
StringBuilder buf = new StringBuilder();
buf.append("[id: ").append(entry.getId()).append("]");
buf.append("[route: ").append(entry.getRoute()).append("]");
Object state = entry.getState();
if (state != null) {
buf.append("[state: ").append(state).append("]");
}
return buf.toString();
}
public ClientConnectionRequest requestConnection(
final HttpRoute route,
final Object state) {
if (route == null) {
throw new IllegalArgumentException("HTTP route may not be null");
}
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() {
public void abortRequest() {
future.cancel(true);
}
public ManagedClientConnection getConnection(
final long timeout,
final TimeUnit tunit) throws InterruptedException, ConnectionPoolTimeoutException {
return leaseConnection(future, timeout, tunit);
}
};
}
ManagedClientConnection leaseConnection(
final Future future,
final long timeout,
final TimeUnit tunit) throws InterruptedException, ConnectionPoolTimeoutException {
HttpPoolEntry entry;
try {
entry = future.get(timeout, tunit);
if (entry == null || future.isCancelled()) {
throw new InterruptedException();
}
if (entry.getConnection() == null) {
throw new IllegalStateException("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 (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 (TimeoutException ex) {
throw new ConnectionPoolTimeoutException("Timeout waiting for connection from pool");
}
}
public void releaseConnection(
final ManagedClientConnection conn, final long keepalive, final TimeUnit tunit) {
if (!(conn instanceof ManagedClientConnectionImpl)) {
throw new IllegalArgumentException
("Connection class mismatch, " +
"connection not obtained from this manager.");
}
ManagedClientConnectionImpl managedConn = (ManagedClientConnectionImpl) conn;
if (managedConn.getManager() != this) {
throw new IllegalStateException("Connection not obtained from this manager.");
}
synchronized (managedConn) {
HttpPoolEntry entry = managedConn.detach();
if (entry == null) {
return;
}
try {
if (managedConn.isOpen() && !managedConn.isMarkedReusable()) {
try {
managedConn.shutdown();
} catch (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, tunit != null ? tunit : TimeUnit.MILLISECONDS);
if (this.log.isDebugEnabled()) {
String s;
if (keepalive > 0) {
s = "for " + keepalive + " " + tunit;
} 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()));
}
}
}
public void shutdown() {
this.log.debug("Connection manager is shutting down");
try {
this.pool.shutdown();
} catch (IOException ex) {
this.log.debug("I/O exception shutting down connection manager", ex);
}
this.log.debug("Connection manager shut down");
}
public void closeIdleConnections(long idleTimeout, TimeUnit tunit) {
if (this.log.isDebugEnabled()) {
this.log.debug("Closing connections idle longer than " + idleTimeout + " " + tunit);
}
this.pool.closeIdle(idleTimeout, tunit);
}
public void closeExpiredConnections() {
this.log.debug("Closing expired connections");
this.pool.closeExpired();
}
public int getMaxTotal() {
return this.pool.getMaxTotal();
}
public void setMaxTotal(int max) {
this.pool.setMaxTotal(max);
}
public int getDefaultMaxPerRoute() {
return this.pool.getDefaultMaxPerRoute();
}
public void setDefaultMaxPerRoute(int max) {
this.pool.setDefaultMaxPerRoute(max);
}
public int getMaxPerRoute(final HttpRoute route) {
return this.pool.getMaxPerRoute(route);
}
public void setMaxPerRoute(final HttpRoute route, int max) {
this.pool.setMaxPerRoute(route, max);
}
public PoolStats getTotalStats() {
return this.pool.getTotalStats();
}
public PoolStats getStats(final HttpRoute route) {
return this.pool.getStats(route);
}
}