/*
 * Copyright (c) 1996, 2008, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package sun.rmi.transport.proxy;

import java.io.*;
import java.net.*;

import sun.rmi.runtime.Log;

The HttpSendSocket class extends the java.net.Socket class
by enclosing the data output stream in, then extracting the input
stream from, an HTTP protocol transmission.
NOTES:
Since the length of the output request must be known before the
HTTP header can be completed, all of the output is buffered by
an HttpOutputStream object until either an attempt is made to
read from this socket, or the socket is explicitly closed.
On the first read attempt to read from this socket, the buffered
output is sent to the destination as the body of an HTTP POST
request.  All reads will then acquire data from the body of
the response.  A subsequent attempt to write to this socket will
throw an IOException.
/**
 * The HttpSendSocket class extends the java.net.Socket class
 * by enclosing the data output stream in, then extracting the input
 * stream from, an HTTP protocol transmission.
 *
 * NOTES:
 *
 * Since the length of the output request must be known before the
 * HTTP header can be completed, all of the output is buffered by
 * an HttpOutputStream object until either an attempt is made to
 * read from this socket, or the socket is explicitly closed.
 *
 * On the first read attempt to read from this socket, the buffered
 * output is sent to the destination as the body of an HTTP POST
 * request.  All reads will then acquire data from the body of
 * the response.  A subsequent attempt to write to this socket will
 * throw an IOException.
 */
class HttpSendSocket extends Socket implements RMISocketInfo {

    
the host to connect to /** the host to connect to */
    protected String host;

    
the port to connect to /** the port to connect to */
    protected int port;

    
the URL to forward through /** the URL to forward through */
    protected URL url;

    
the object managing this connection through the URL /** the object managing this connection through the URL */
    protected URLConnection conn = null;

    
internal input stream for this socket /** internal input stream for this socket */
    protected InputStream in = null;

    
internal output stream for this socket /** internal output stream for this socket */
    protected OutputStream out = null;

    
the notifying input stream returned to users /** the notifying input stream returned to users */
    protected HttpSendInputStream inNotifier;

    
the notifying output stream returned to users /** the notifying output stream returned to users */
    protected HttpSendOutputStream outNotifier;

    
Line separator string.  This is the value of the line.separator
property at the moment that the socket was created.
/**
     * Line separator string.  This is the value of the line.separator
     * property at the moment that the socket was created.
     */
    private String lineSeparator =
        java.security.AccessController.doPrivileged(
            new sun.security.action.GetPropertyAction("line.separator"));

    
Create a stream socket and connect it to the specified port on
the specified host.
Params:
host – the host
port – the port/**
     * Create a stream socket and connect it to the specified port on
     * the specified host.
     * @param host the host
     * @param port the port
     */
    public HttpSendSocket(String host, int port, URL url) throws IOException
    {
        super((SocketImpl)null);        // no underlying SocketImpl for this object

        if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.VERBOSE)) {
            RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE,
                "host = " + host + ", port = " + port + ", url = " + url);
        }

        this.host = host;
        this.port = port;
        this.url = url;

        inNotifier = new HttpSendInputStream(null, this);
        outNotifier = new HttpSendOutputStream(writeNotify(), this);
    }

    
Create a stream socket and connect it to the specified port on
the specified host.
Params:
host – the host
port – the port/**
     * Create a stream socket and connect it to the specified port on
     * the specified host.
     * @param host the host
     * @param port the port
     */
    public HttpSendSocket(String host, int port) throws IOException
    {
        this(host, port, new URL("http", host, port, "/"));
    }

    
Create a stream socket and connect it to the specified address on
the specified port.
Params:
address – the address
port – the port/**
     * Create a stream socket and connect it to the specified address on
     * the specified port.
     * @param address the address
     * @param port the port
     */
    public HttpSendSocket(InetAddress address, int port) throws IOException
    {
        this(address.getHostName(), port);
    }

    
Indicate that this socket is not reusable.
/**
     * Indicate that this socket is not reusable.
     */
    public boolean isReusable()
    {
        return false;
    }

    
Create a new socket connection to host (or proxy), and prepare to
send HTTP transmission.
/**
     * Create a new socket connection to host (or proxy), and prepare to
     * send HTTP transmission.
     */
    public synchronized OutputStream writeNotify() throws IOException
    {
        if (conn != null) {
            throw new IOException("attempt to write on HttpSendSocket after " +
                                  "request has been sent");
        }

        conn = url.openConnection();
        conn.setDoOutput(true);
        conn.setUseCaches(false);
        conn.setRequestProperty("Content-type", "application/octet-stream");

        inNotifier.deactivate();
        in = null;

        return out = conn.getOutputStream();
    }

    
Send HTTP output transmission and prepare to receive response.
/**
     * Send HTTP output transmission and prepare to receive response.
     */
    public synchronized InputStream readNotify() throws IOException
    {
        RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE,
            "sending request and activating input stream");

        outNotifier.deactivate();
        out.close();
        out = null;

        try {
            in = conn.getInputStream();
        } catch (IOException e) {
            RMIMasterSocketFactory.proxyLog.log(Log.BRIEF,
                "failed to get input stream, exception: ", e);

            throw new IOException("HTTP request failed");
        }

        /*
         * If an HTTP error response is returned, sometimes an IOException
         * is thrown, which is handled above, and other times it isn't, and
         * the error response body will be available for reading.
         * As a safety net to catch any such unexpected HTTP behavior, we
         * verify that the content type of the response is what the
         * HttpOutputStream generates: "application/octet-stream".
         * (Servers' error responses will generally be "text/html".)
         * Any error response body is printed to the log.
         */
        String contentType = conn.getContentType();
        if (contentType == null ||
            !conn.getContentType().equals("application/octet-stream"))
        {
            if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.BRIEF)) {
                String message;
                if (contentType == null) {
                    message = "missing content type in response" +
                        lineSeparator;
                } else {
                    message = "invalid content type in response: " +
                        contentType + lineSeparator;
                }

                message += "HttpSendSocket.readNotify: response body: ";
                try {
                    BufferedReader din = new BufferedReader(new InputStreamReader(in));
                    String line;
                    while ((line = din.readLine()) != null)
                        message += line + lineSeparator;
                } catch (IOException e) {
                }
                RMIMasterSocketFactory.proxyLog.log(Log.BRIEF, message);
            }

            throw new IOException("HTTP request failed");
        }

        return in;
    }

    
Get the address to which the socket is connected.
/**
     * Get the address to which the socket is connected.
     */
    public InetAddress getInetAddress()
    {
        try {
            return InetAddress.getByName(host);
        } catch (UnknownHostException e) {
            return null;        // null if couldn't resolve destination host
        }
    }

    
Get the local address to which the socket is bound.
/**
     * Get the local address to which the socket is bound.
     */
    public InetAddress getLocalAddress()
    {
        try {
            return InetAddress.getLocalHost();
        } catch (UnknownHostException e) {
            return null;        // null if couldn't determine local host
        }
    }

    
Get the remote port to which the socket is connected.
/**
     * Get the remote port to which the socket is connected.
     */
    public int getPort()
    {
        return port;
    }

    
Get the local port to which the socket is connected.
/**
     * Get the local port to which the socket is connected.
     */
    public int getLocalPort()
    {
        return -1;      // request not applicable to this socket type
    }

    
Get an InputStream for this socket.
/**
     * Get an InputStream for this socket.
     */
    public InputStream getInputStream() throws IOException
    {
        return inNotifier;
    }

    
Get an OutputStream for this socket.
/**
     * Get an OutputStream for this socket.
     */
    public OutputStream getOutputStream() throws IOException
    {
        return outNotifier;
    }

    
Enable/disable TCP_NODELAY.
This operation has no effect for an HttpSendSocket.
/**
     * Enable/disable TCP_NODELAY.
     * This operation has no effect for an HttpSendSocket.
     */
    public void setTcpNoDelay(boolean on) throws SocketException
    {
    }

    
Retrieve whether TCP_NODELAY is enabled.
/**
     * Retrieve whether TCP_NODELAY is enabled.
     */
    public boolean getTcpNoDelay() throws SocketException
    {
        return false;   // imply option is disabled
    }

    
Enable/disable SO_LINGER with the specified linger time.
This operation has no effect for an HttpSendSocket.
/**
     * Enable/disable SO_LINGER with the specified linger time.
     * This operation has no effect for an HttpSendSocket.
     */
    public void setSoLinger(boolean on, int val) throws SocketException
    {
    }

    
Retrive setting for SO_LINGER.
/**
     * Retrive setting for SO_LINGER.
     */
    public int getSoLinger() throws SocketException
    {
        return -1;      // imply option is disabled
    }

    
Enable/disable SO_TIMEOUT with the specified timeout
This operation has no effect for an HttpSendSocket.
/**
     * Enable/disable SO_TIMEOUT with the specified timeout
     * This operation has no effect for an HttpSendSocket.
     */
    public synchronized void setSoTimeout(int timeout) throws SocketException
    {
    }

    
Retrive setting for SO_TIMEOUT.
/**
     * Retrive setting for SO_TIMEOUT.
     */
    public synchronized int getSoTimeout() throws SocketException
    {
        return 0;       // imply option is disabled
    }

    
Close the socket.
/**
     * Close the socket.
     */
    public synchronized void close() throws IOException
    {
        if (out != null) // push out transmission if not done
            out.close();
    }

    
Return string representation of this pseudo-socket.
/**
     * Return string representation of this pseudo-socket.
     */
    public String toString()
    {
        return "HttpSendSocket[host=" + host +
               ",port=" + port +
               ",url=" + url + "]";
    }
}