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Tomcat example source code file (

This example Tomcat source code file ( is included in the "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Tomcat tags/keywords

exception, io, ioexception, jkhandler, jkhandler, last=1, management, msgcontext, msgcontext, object, objectname, objectname, properties, string, string, util, workerenv

The Tomcat source code

 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.

package org.apache.jk.core;

import java.util.Properties;


import org.apache.tomcat.util.modeler.Registry;

 * @author Costin Manolache
public class JkHandler implements MBeanRegistration, NotificationListener {
    public static final int OK=0;
    public static final int LAST=1;
    public static final int ERROR=2;

    protected Properties properties=new Properties();
    protected WorkerEnv wEnv;
    protected JkHandler next;
    protected String nextName=null;
    protected String name;
    protected int id;

    // XXX Will be replaced with notes and (configurable) ids
    // Each represents a 'chain' - similar with ActionCode in Coyote ( the concepts
    // will be merged ).    
    public static final int HANDLE_RECEIVE_PACKET   = 10;
    public static final int HANDLE_SEND_PACKET      = 11;
    public static final int HANDLE_FLUSH            = 12;
    public static final int HANDLE_THREAD_END       = 13;
    public void setWorkerEnv( WorkerEnv we ) {

    /** Set the name of the handler. Will allways be called by
     *  worker env after creating the worker.
    public void setName(String s ) {

    public String getName() {
        return name;

    /** Set the id of the worker. We use an id for faster dispatch.
     *  Since we expect a decent number of handler in system, the
     *  id is unique - that means we may have to allocate bigger
     *  dispatch tables. ( easy to fix if needed )
    public void setId( int id ) {;

    public int getId() {
        return id;
    /** Catalina-style "recursive" invocation.
     *  A chain is used for Apache/3.3 style iterative invocation.
    public void setNext( JkHandler h ) {

    public void setNext( String s ) {

    public String getNext() {
        if( nextName==null ) {
            if( next!=null)
        return nextName;

    /** Should register the request types it can handle,
     *   same style as apache2.
    public void init() throws IOException {

    /** Clean up and stop the handler
    public void destroy() throws IOException {

    public MsgContext createMsgContext() {
        return new MsgContext(8*1024);
    public MsgContext createMsgContext(int bsize) {
        return new MsgContext(bsize);

    public int invoke(Msg msg, MsgContext mc )  throws IOException {
        return OK;
    public void setProperty( String name, String value ) {
        properties.put( name, value );

    public String getProperty( String name ) {
        return properties.getProperty(name) ;

    /** Experimental, will be replaced. This allows handlers to be
     *  notified when other handlers are added.
    public void addHandlerCallback( JkHandler w ) {


    public void handleNotification(Notification notification, Object handback)
//        BaseNotification bNot=(BaseNotification)notification;
//        int code=bNot.getCode();
//        MsgContext ctx=(MsgContext)bNot.getSource();


    protected String domain;
    protected ObjectName oname;
    protected MBeanServer mserver;

    public ObjectName getObjectName() {
        return oname;

    public String getDomain() {
        return domain;

    public ObjectName preRegister(MBeanServer server,
                                  ObjectName oname) throws Exception {
        if( name==null ) {
        // we need to create a workerEnv or set one.
        ObjectName wEnvName=new ObjectName(domain + ":type=JkWorkerEnv");
        if ( wEnv == null ) {
            wEnv=new WorkerEnv();
        if( ! mserver.isRegistered(wEnvName )) {
            Registry.getRegistry(null, null).registerComponent(wEnv, wEnvName, null);
        mserver.invoke( wEnvName, "addHandler", 
                new Object[] {name, this}, 
                new String[] {"java.lang.String", 
        return oname;
    public void postRegister(Boolean registrationDone) {

    public void preDeregister() throws Exception {

    public void postDeregister() {

    public void pause() throws Exception {

    public void resume() throws Exception {


Other Tomcat examples (source code examples)

Here is a short list of links related to this Tomcat source code file:

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