jk/common/HandlerDispatch.java

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package org.apache.jk.common;

import java.io.IOException;
import java.util.logging.*;

import org.apache.jk.core.JkHandler;
import org.apache.jk.core.Msg;
import org.apache.jk.core.MsgContext;


/**
 * Dispatch based on the message type. ( XXX make it more generic,
 * now it's specific to ajp13 ).
 *
 * @author Costin Manolache
 */
public class HandlerDispatch extends JkHandler
{
    private static Logger log=
        Logger.getLogger( HandlerDispatch.class.getName() );

    public HandlerDispatch()
    {
    }

    public void init() {
    }

    JkHandler handlers[]=new JkHandler[MAX_HANDLERS];
    String handlerNames[]=new String[MAX_HANDLERS];

    static final int MAX_HANDLERS=32;
    static final int RESERVED=16;  // reserved names, backward compat
    int currentId=RESERVED;

    public int registerMessageType( int id, String name, JkHandler h,
                                    String sig[] )
    {
        if( log.isLoggable(Level.FINEST) )
            log.finest( "Register message " + id + " " + h.getName() +
                 " " + h.getClass().getName());
    if( id < 0 ) {
        // try to find it by name
        for( int i=0; i< handlerNames.length; i++ ) {
                if( handlerNames[i]==null ) continue;
                if( name.equals( handlerNames[i] ) )
                    return i;
            }
        handlers[currentId]=h;
            handlerNames[currentId]=name;
        currentId++;
        return currentId;
    }
    handlers[id]=h;
        handlerNames[currentId]=name;
    return id;
    }


    // -------------------- Incoming message --------------------

    public int invoke(Msg msg, MsgContext ep )
        throws IOException
    {
        int type=msg.peekByte();
        ep.setType( type );

        if( type > handlers.length ||
            handlers[type]==null ) {
        if( log.isLoggable(Level.FINEST) )
                log.finest( "Invalid handler " + type );
        return ERROR;
    }

        if( log.isLoggable(Level.FINEST) )
            log.finest( "Received " + type + " " + handlers[type].getName());

    JkHandler handler=handlers[type];

        return handler.invoke( msg, ep );
    }

 }