Java tutorial
/** * Copyright 2005-2014 Red Hat, Inc. * * Red Hat 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 com.beyondjservlet.gateway.servlet.support; import org.apache.commons.httpclient.HttpConnection; import org.apache.commons.httpclient.params.HttpConnectionParams; import org.apache.commons.httpclient.protocol.DefaultProtocolSocketFactory; import org.apache.commons.httpclient.protocol.ProtocolSocketFactory; import java.io.IOException; import java.net.InetAddress; import java.net.Socket; /** * A @{link ProtocolSocketFactory} implementation that does not bind a socket. * <p> * * The reason for this {@link ProtocolSocketFactory} implementation is that for ProxyServlet we don't need to * bind to a local address and port. This binding can cause issue in PaaS environments where restrictions apply. * <p> * * When {@link HttpConnection#open()} calls * {@link ProtocolSocketFactory#createSocket(String, int, InetAddress, int, HttpConnectionParams)} * which by default will use {@link DefaultProtocolSocketFactory#createSocket(String, int, InetAddress, int, HttpConnectionParams)}. * The method that will be invoke is {@link DefaultProtocolSocketFactory#createSocket(String, int, InetAddress, int, HttpConnectionParams)} * which will call {@code return new Socket(host, port, localAddress, localPort);}. * The {@link Socket#Socket(InetAddress, int, InetAddress, int)} constructor will create a new Socket and connect to the * remote address and port (the first two arguments). It will also bind() to the local address and port. This is * the part that can cause issue in PaaS environment where there are restrictions. * */ public class NonBindingSocketFactory implements ProtocolSocketFactory { @Override public Socket createSocket(String host, int port, InetAddress localAddress, int localPort) throws IOException { return createNonBindingSocket(host, port); } @Override public Socket createSocket(String host, int port, InetAddress localAddress, int localPort, HttpConnectionParams params) throws IOException { return createNonBindingSocket(host, port); } @Override public Socket createSocket(String host, int port) throws IOException { return createNonBindingSocket(host, port); } private static Socket createNonBindingSocket(String host, int port) throws IOException { return new Socket(host, port); } }