sdpmessage.java

Java SIP

/*
 * This file was derived from libdissipate, an open source SIP library. The original file 
 * was modified on 1/23/2001.  Please see
 * http://www.div8.net/dissipate for more information.
 *
 * Copyright (c) 2000 Billy Biggs <[e-mail]>
 *
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Library General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 * 
 * This library 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 Library General Public
 * License for more details.
 * 
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 *
 */
/**
 * class SdpMessage
 * 
 * Class for representing an SDP message.
 *
 * This code has been generated using C2J++
 * C2J++ is based on Chris Laffra's C2J ([e-mail])
 * Read general disclaimer distributed with C2J++ before using this code
 * For information about C2J++, send mail to [e-mail]
 */
package org.mitre.jsip;

import java.util.Date;

public class SdpMessage
{
    
    /**
     * Construct a blank SDP message object.
     */
    public SdpMessage()
    {
	valid = true;
	port = 0;
	payload_types = new int[1];
	payload_types[0] = 0;  // set gsm as a default
    }

    /**
     * Parse the given SDP message.
     *
     * @param parseinput
     */
    public SdpMessage(String parseinput)
    {
	parseInput( parseinput );
    }

    /**
     * Returns true if the parsed SDP message is valid.
     *
     * @return bool
     */
    public boolean isValid()
    { return valid; }

    /**
     * Returns true if this SDP implies the call is on hold.
     *
     * @return bool
     */
    public boolean isOnHold()
    {
	return ( ipaddress.trim() == "0.0.0.0" );
    }

    /**
     * Returns the unique session name.  This is the s= line of SDP.
     *
     * @return String
     */
    public String getName()
    { return sessionname; }

    /**
     * Returns the IP address of the session described.
     *
     * @return String
     */
    public String getIpAddress()
    { return ipaddress; }

    /**
     * Returns the port on which media is being received.
     *
     * @return int
     */
    public int getPort()
    { return port; }

    /**
     * Sets the IP address to which media should be directed.
     *
     * @param newaddr
     */
    public void setIpAddress(String newaddr)
    {
	ipaddress = newaddr;
    }

    /**
     * Sets the port on which media is to be received.
     *
     * @param newport
     */
    public void setPort(int newport)
    {
	port = newport;
    }
    
    /**
     * Sets the name of the session (the SDP s= line).
     *
     * @param newname
     */
    public void setName(String newname)
    {
	sessionname = newname;
    }

    /**
     * Sets the username (for the SDP o= line).
     *
     * @param username
     */
    public void setUsername(String username)
    {
	this.username = username;
    }

    /**
     * Sets the payload types (for the SDP m= line)
     *
     * @param types The payload types the application can use
     */
    public void setPayloadTypes(int[] types) 
    {
	payload_types = new int[types.length];
	System.arraycopy(types, 0, payload_types, 0, types.length);
    }

    /**
     * Parses the given input as an SDP message.
     *
     * @param parseinput
     */
    public void parseInput(String parseinput)
    {
	String input = parseinput;
	String curline;
	String portstr;
	String codecstr;
	valid = false;

	port = 0;
	ipaddress = null;

	// Guarentee termination
	input += '\n';

	if( input.substring( 0, input.indexOf( '\n' ) - 1 ) != "v=0" ) {
	    return;
	}
	input = input.substring( input.indexOf( '\n' ) + 1 );

	while( input.length() > 0 ) {
		curline = input.substring( 0, input.indexOf( '\n' ) - 1 );
		input = input.substring( input.indexOf( '\n' ) + 1 );

		if( curline.substring( 0, curline.indexOf( '=' ) - 1 ) == "c" ) {
		    ipaddress = curline.substring( curline.indexOf( "IP4" ) + 4 ).trim();
		}

		if( curline.substring( 0, curline.indexOf( '=' ) - 1 ) == "m" ) {
		    portstr = curline.substring( curline.indexOf( "audio" ) + 5 );
		    portstr = portstr.substring( 0, portstr.indexOf( "RTP" ) - 1 ).trim();

		    // fix for ericsson
		    if( portstr.indexOf( '/' ) >= 0 ) {
			if (SipClient.DEBUG) System.out.println( "SdpMessage: Uh-oh, ericsson is calling again" );
			portstr = portstr.substring( 0, portstr.indexOf( '/' ) - 1 ).trim();
		    }

		    codecstr = curline.substring( curline.indexOf( "AVP" ) + 4 ).trim();
		    
		    codecstr = " " + codecstr + " "; // ????
		    if( codecstr.indexOf( " 0 " ) >= 0 ) {
			try {
			    port = Integer.parseInt(portstr);
			    if (SipClient.DEBUG) System.out.println( "SdpMessage: We found a match! (port " + port + ")" );
			} catch (NumberFormatException nfe) {
			    System.err.println("couldn't parse port string. Setting to default");
			    port = 5060;
			}
		    }
		}
	}
	
	valid = true;
    }

    /**
     * Builds and returns an SDP message given the contents.
     *
     * @return String
     */
    public String message()
    {
	Date date = new Date();   // to make a timestamp.

	String msg = "";

	// Version
	msg += "v=0\r\n";
	
	// Session Id
	msg += "o=" + username + " " + String.valueOf( date.getTime() ) + " 0 IN IP4 " + SipUtil.getLocalFqdn() + "\r\n";

	// Session Name
	msg += "s=" + sessionname + "\r\n";
	
	// Connection Info
	msg += "c=IN IP4 " + ipaddress + "\r\n";

	// Time active
	msg += "t=0 0\r\n";

	// Media information
	msg += "m=audio " + String.valueOf( port ) + " RTP/AVP " + createPayloadString() + "\r\n";

	// rtpmap
	msg += "a=rtpmap:0 PCMU/8000\r\n";

	// more fixes for nortel
	msg += "a=ptime:20\r\n";


	return msg;
    }

    private String createPayloadString() {
	String ret = "";

	for (int i = 0; i < payload_types.length; i++) 
	    ret += String.valueOf(payload_types[i]) + " ";

	return ret;
    }

    /**
     * test out SdpMessage
     */

    public static void main(String[] args) {
	int [] payloadTypes = {0, 3};
	String mcastAddr = "225.5.5.5";
	int mcastPort = 25555;

	// create a message from scratch and print it out
	SdpMessage sdpMessage = new SdpMessage();
	sdpMessage.setName("jSIP");
	sdpMessage.setUsername("steve");
	sdpMessage.setPayloadTypes(payloadTypes);
	sdpMessage.setIpAddress(mcastAddr);
	sdpMessage.setPort(mcastPort);

	System.out.println("Test message is\n" + sdpMessage.message());
    }

    // class variables
    private boolean valid;
    private String sessionname;
    private String ipaddress;
    private String username = "Unknown";
    private int port;
    private int[] payload_types;
}