Java tutorial
/* * ==================================================================== * 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 * <http://www.apache.org/>. * */ package org.apache.http.impl.conn; import java.io.IOException; import java.net.ConnectException; import java.net.InetAddress; import java.net.InetSocketAddress; import java.net.Socket; import java.net.SocketTimeoutException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.http.HttpHost; import org.apache.http.annotation.Immutable; import org.apache.http.client.protocol.HttpClientContext; import org.apache.http.config.Lookup; import org.apache.http.config.SocketConfig; import org.apache.http.conn.ConnectTimeoutException; import org.apache.http.conn.DnsResolver; import org.apache.http.conn.HttpHostConnectException; import org.apache.http.conn.ManagedHttpClientConnection; import org.apache.http.conn.SchemePortResolver; import org.apache.http.conn.UnsupportedSchemeException; import org.apache.http.conn.socket.ConnectionSocketFactory; import org.apache.http.conn.socket.LayeredConnectionSocketFactory; import org.apache.http.protocol.HttpContext; import org.apache.http.util.Args; @Immutable class HttpClientConnectionOperator { static final String SOCKET_FACTORY_REGISTRY = "http.socket-factory-registry"; private final Log log = LogFactory.getLog(getClass()); private final Lookup<ConnectionSocketFactory> socketFactoryRegistry; private final SchemePortResolver schemePortResolver; private final DnsResolver dnsResolver; HttpClientConnectionOperator(final Lookup<ConnectionSocketFactory> socketFactoryRegistry, final SchemePortResolver schemePortResolver, final DnsResolver dnsResolver) { super(); Args.notNull(socketFactoryRegistry, "Socket factory registry"); this.socketFactoryRegistry = socketFactoryRegistry; this.schemePortResolver = schemePortResolver != null ? schemePortResolver : DefaultSchemePortResolver.INSTANCE; this.dnsResolver = dnsResolver != null ? dnsResolver : SystemDefaultDnsResolver.INSTANCE; } @SuppressWarnings("unchecked") private Lookup<ConnectionSocketFactory> getSocketFactoryRegistry(final HttpContext context) { Lookup<ConnectionSocketFactory> reg = (Lookup<ConnectionSocketFactory>) context .getAttribute(SOCKET_FACTORY_REGISTRY); if (reg == null) { reg = this.socketFactoryRegistry; } return reg; } public void connect(final ManagedHttpClientConnection conn, final HttpHost host, final InetSocketAddress localAddress, final int connectTimeout, final SocketConfig socketConfig, final HttpContext context) throws IOException { final Lookup<ConnectionSocketFactory> registry = getSocketFactoryRegistry(context); final ConnectionSocketFactory sf = registry.lookup(host.getSchemeName()); if (sf == null) { throw new UnsupportedSchemeException(host.getSchemeName() + " protocol is not supported"); } final InetAddress[] addresses = this.dnsResolver.resolve(host.getHostName()); final int port = this.schemePortResolver.resolve(host); for (int i = 0; i < addresses.length; i++) { final InetAddress address = addresses[i]; final boolean last = i == addresses.length - 1; Socket sock = sf.createSocket(context); sock.setReuseAddress(socketConfig.isSoReuseAddress()); conn.bind(sock); final InetSocketAddress remoteAddress = new InetSocketAddress(address, port); if (this.log.isDebugEnabled()) { this.log.debug("Connecting to " + remoteAddress); } try { sock.setSoTimeout(socketConfig.getSoTimeout()); sock = sf.connectSocket(connectTimeout, sock, host, remoteAddress, localAddress, context); sock.setTcpNoDelay(socketConfig.isTcpNoDelay()); sock.setKeepAlive(socketConfig.isSoKeepAlive()); final int linger = socketConfig.getSoLinger(); if (linger >= 0) { sock.setSoLinger(linger > 0, linger); } conn.bind(sock); if (this.log.isDebugEnabled()) { this.log.debug("Connection established " + conn); } return; } catch (final SocketTimeoutException ex) { if (last) { throw new ConnectTimeoutException(ex, host, addresses); } } catch (final ConnectException ex) { if (last) { final String msg = ex.getMessage(); if ("Connection timed out".equals(msg)) { throw new ConnectTimeoutException(ex, host, addresses); } else { throw new HttpHostConnectException(ex, host, addresses); } } } if (this.log.isDebugEnabled()) { this.log.debug("Connect to " + remoteAddress + " timed out. " + "Connection will be retried using another IP address"); } } } public void upgrade(final ManagedHttpClientConnection conn, final HttpHost host, final HttpContext context) throws IOException { final HttpClientContext clientContext = HttpClientContext.adapt(context); final Lookup<ConnectionSocketFactory> registry = getSocketFactoryRegistry(clientContext); final ConnectionSocketFactory sf = registry.lookup(host.getSchemeName()); if (sf == null) { throw new UnsupportedSchemeException(host.getSchemeName() + " protocol is not supported"); } if (!(sf instanceof LayeredConnectionSocketFactory)) { throw new UnsupportedSchemeException( host.getSchemeName() + " protocol does not support connection upgrade"); } final LayeredConnectionSocketFactory lsf = (LayeredConnectionSocketFactory) sf; Socket sock = conn.getSocket(); final int port = this.schemePortResolver.resolve(host); sock = lsf.createLayeredSocket(sock, host.getHostName(), port, context); conn.bind(sock); } }