registrar.java

First of all, the Applet-phone is a SIP User-Agent with audio and text messaging capabilities. But

/*
 * Registrar.java
 *
 * Created on June 27, 2002, 11:16 AM
 */

package gov.nist.examples.bps.registrar;

import javax.sip.*;
import javax.sip.message.*; 
import javax.sip.header.*;
import javax.sip.address.*;
import java.util.*;
import gov.nist.examples.bps.gateway.*;
/**
 *
 * @author  deruelle
 * @version 1.0
 */
public class Registrar  {

    protected  RegistrationsTable registrationsTable;
   
    // in seconds
    public static int EXPIRES_TIME_MIN=1;
    public static int EXPIRES_TIME_MAX=36000;
    
    protected String xmlRegistrationsFile;
    protected Gateway gateway;
    
    /**
     *  Creates new Registrar
     */
    public Registrar(Gateway gateway)  {
        registrationsTable=new RegistrationsTable(this);
        this.gateway=gateway;
    }
 
     public void setExpiresTime(int expiresTime) {
        EXPIRES_TIME_MAX=expiresTime;
     }
 
    public RegistrationsTable getRegistrationsTable() {
        return registrationsTable;
    }
  
    /** Process the register message: add, remove, update the bindings
     *  and manage also the expiration time.
     *  @param Request Register message to set
     *  @return int status code of the process of the Register.
     */
    public
    synchronized void processRegister(Request request, SipProvider sipProvider,
    ServerTransaction serverTransaction ) {
        try{
            MessageFactory messageFactory=gateway.getMessageFactory();
            
            String key=getKey(request);
            // Add the key if it is a new user:
            if (GatewayDebug.debug){
                GatewayDebug.println
                ("Registrar, processRegister(), key: \""+key+"\"");
            }
            if (key==null){
                if (GatewayDebug.debug) {
                    GatewayDebug.println
                    ("Registrar, processRegister(), key is null"+
                    " 400 INVALID REQUEST replied");
                }
                Response response=messageFactory.createResponse
                (Response.BAD_REQUEST,request);
                if (serverTransaction!=null)
                   serverTransaction.sendResponse(response);
                else sipProvider.sendResponse(response);
                return ;
            }
            
          
            // RFC 3261: 10.3:
            /*  6. The registrar checks whether the request contains the Contact
         header field.  If not, it skips to the last step.  If the
         Contact header field is present, the registrar checks if there
         is one Contact field value that contains the special value "*"
         and an Expires field.  If the request has additional Contact
         fields or an expiration time other than zero, the request is
         invalid, and the server MUST return a 400 (Invalid Request) and
         skip the remaining steps.  If not, the registrar checks whether
         the Call-ID agrees with the value stored for each binding.  If
         not, it MUST remove the binding.  If it does agree, it MUST
         remove the binding only if the CSeq in the request is higher
         than the value stored for that binding.  Otherwise, the update
         MUST be aborted and the request fails.
            */
            
            if ( !hasContactHeaders(request) ) {
                Vector contactHeaders=getContactHeaders(key);
                Response response=messageFactory.createResponse
                (Response.OK,request);
                if ( contactHeaders!=null ) {
                    for (int i = 0 ; i < contactHeaders.size(); i++) {
                        ContactHeader contact = (ContactHeader)
                        contactHeaders.elementAt(i);
                        response.addHeader(contact);
                    }
                }
              
                if (serverTransaction!=null)
                    serverTransaction.sendResponse(response);
                else sipProvider.sendResponse(response);
                if (GatewayDebug.debug) {
                    GatewayDebug.println
                    ("Registrar, processRegister(), response sent:"+response.toString());
                }
                return;
            }
            
            
            // bug report by Alistair Coles
            if ( hasStar(request) ) {
                Vector contactHeaders=getContactHeaders(key);
                if (contactHeaders.size()>1) {
                    if (GatewayDebug.debug) {
                        GatewayDebug.println
                        ("Registrar, processRegister(), more than one contact header"+
                        " is present at the same time as a wild card."+
                        " 400 INVALID REQUEST replied");
                    }
                    Response response=messageFactory.createResponse
                    (Response.BAD_REQUEST,request);
                     if (serverTransaction!=null)
                        serverTransaction.sendResponse(response);
                    else sipProvider.sendResponse(response);
                    if (GatewayDebug.debug) {
                        GatewayDebug.println
                        ("Registrar, processRegister(), response sent:");
                        GatewayDebug.print(response.toString());
                    }
                    return ;
                }
                
                if ( !hasExpiresZero(request) ) {
                    if (GatewayDebug.debug) {
                        GatewayDebug.println
                        ("Registrar, processRegister(), expires time different from"+
                        " 0 with a wild card."+
                        " 400 INVALID REQUEST replied");
                    }
                    Response response=messageFactory.createResponse
                    (Response.BAD_REQUEST,request);
                    
                    if (serverTransaction!=null)
                        serverTransaction.sendResponse(response);
                    else sipProvider.sendResponse(response); 
                    if (GatewayDebug.debug) {
                        GatewayDebug.println
                        ("Registrar, processRegister(), response sent:");
                        GatewayDebug.print(response.toString());
                    }
                    return ;
                }
                
                if (GatewayDebug.debug) {
                    GatewayDebug.println
                    ("Registrar, processRegister(), (* and expires=0) "+
                    " we remove the registration!!");
                }
                registrationsTable.removeRegistration(key);
                
                Response response=messageFactory.createResponse
                (Response.OK,request);
                
                if (serverTransaction!=null)
                    serverTransaction.sendResponse(response);
                else sipProvider.sendResponse(response); 
                    
                if (GatewayDebug.debug) {
                    GatewayDebug.println
                    ("Registrar, processRegister(), response sent:");
                    GatewayDebug.print(response.toString());
                }
                return;
            }
            
           
            if ( registrationsTable.hasRegistration(key) ) {
               
                registrationsTable.updateRegistration(key,request);
                Vector contactHeaders=getContactHeaders(key);
                Response response=
                messageFactory.createResponse(Response.OK,request);
                if ( contactHeaders!=null ) {
                    for (int i = 0; i < contactHeaders.size(); i++) {
                        ContactHeader contact = (ContactHeader)
                        contactHeaders.elementAt(i);
                        response.addHeader(contact);
                    }
                }
               
                 if (serverTransaction!=null)
                    serverTransaction.sendResponse(response);
                else sipProvider.sendResponse(response); 
                 
                if (GatewayDebug.debug)  {
                    GatewayDebug.println
                    ("Registrar, processRegister(), response sent:");
                    GatewayDebug.print(response.toString());
                }
            }
            else {
                // Let's check the Expires header:
                if ( hasExpiresZero(request) ) {
                    // This message is lost....
                
                    GatewayDebug.println("Registrar, processRegister(), "+
                    "we don't have any record for this REGISTER.");
                    Response response=messageFactory.createResponse
                    (Response.OK,request);
                    
                    if (serverTransaction!=null)
                        serverTransaction.sendResponse(response);
                    else sipProvider.sendResponse(response); 
                    if (GatewayDebug.debug) {
                        GatewayDebug.println
                        ("Registrar, processRegister(), response sent:");
                        GatewayDebug.print(response.toString());
                    }
                    return;