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 * Copyright (c) 1996, 2005, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.rmi.transport.proxy;

import java.io.BufferedInputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import sun.rmi.runtime.Log;

The HttpAwareServerSocket class extends the java.net.ServerSocket
class.  It behaves like a ServerSocket, except that if
the first four bytes of an accepted socket are the letters "POST",
then it returns an HttpReceiveSocket instead of a java.net.Socket.
This means that the accept method blocks until four bytes have been
read from the new socket's input stream.
/**
 * The HttpAwareServerSocket class extends the java.net.ServerSocket
 * class.  It behaves like a ServerSocket, except that if
 * the first four bytes of an accepted socket are the letters "POST",
 * then it returns an HttpReceiveSocket instead of a java.net.Socket.
 * This means that the accept method blocks until four bytes have been
 * read from the new socket's input stream.
 */
class HttpAwareServerSocket extends ServerSocket {

    
Create a server socket on a specified port.
Params:
port – the port
Throws:
IOException – IO error when opening the socket./**
     * Create a server socket on a specified port.
     * @param port the port
     * @exception IOException IO error when opening the socket.
     */
    public HttpAwareServerSocket(int port) throws IOException
    {
        super(port);
    }

    
Create a server socket, bind it to the specified local port
and listen to it.  You can connect to an annonymous port by
specifying the port number to be 0.  backlog specifies
how many connection requests the system will queue up while waiting
for the ServerSocket to execute accept().
Params:
port – the specified port
backlog – the number of queued connect requests pending accept/**
     * Create a server socket, bind it to the specified local port
     * and listen to it.  You can connect to an annonymous port by
     * specifying the port number to be 0.  <i>backlog</i> specifies
     * how many connection requests the system will queue up while waiting
     * for the ServerSocket to execute accept().
     * @param port the specified port
     * @param backlog the number of queued connect requests pending accept
     */
    public HttpAwareServerSocket(int port, int backlog) throws IOException
    {
        super(port, backlog);
    }

    
Accept a connection. This method will block until the connection
is made and four bytes can be read from the input stream.
If the first four bytes are "POST", then an HttpReceiveSocket is
returned, which will handle the HTTP protocol wrapping.
Otherwise, a WrappedSocket is returned.  The input stream will be
reset to the beginning of the transmission.
In either case, a BufferedInputStream will already be on top of
the underlying socket's input stream.
Throws:
IOException – IO error when waiting for the connection./**
     * Accept a connection. This method will block until the connection
     * is made and four bytes can be read from the input stream.
     * If the first four bytes are "POST", then an HttpReceiveSocket is
     * returned, which will handle the HTTP protocol wrapping.
     * Otherwise, a WrappedSocket is returned.  The input stream will be
     * reset to the beginning of the transmission.
     * In either case, a BufferedInputStream will already be on top of
     * the underlying socket's input stream.
     * @exception IOException IO error when waiting for the connection.
     */
    public Socket accept() throws IOException
    {
        Socket socket = super.accept();
        BufferedInputStream in =
            new BufferedInputStream(socket.getInputStream());

        RMIMasterSocketFactory.proxyLog.log(Log.BRIEF,
            "socket accepted (checking for POST)");

        in.mark(4);
        boolean isHttp = (in.read() == 'P') &&
                         (in.read() == 'O') &&
                         (in.read() == 'S') &&
                         (in.read() == 'T');
        in.reset();

        if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.BRIEF)) {
            RMIMasterSocketFactory.proxyLog.log(Log.BRIEF,
                (isHttp ? "POST found, HTTP socket returned" :
                          "POST not found, direct socket returned"));
        }

        if (isHttp)
            return new HttpReceiveSocket(socket, in, null);
        else
            return new WrappedSocket(socket, in, null);
    }

    
Return the implementation address and implementation port of
the HttpAwareServerSocket as a String.
/**
     * Return the implementation address and implementation port of
     * the HttpAwareServerSocket as a String.
     */
    public String toString()
    {
        return "HttpAware" + super.toString();
    }
}