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Tomcat example source code file (ReplicatedContext.java)

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

Java - Tomcat tags/keywords

classloader, enumeration, enumeration, failed, lifecycleexception, lifecycleexception, multienumeration, object, object, replapplcontext, replicatedcontext, replicatedcontext, replicatedmap, servlet, threading, threads, unable, util

The Tomcat ReplicatedContext.java 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
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * 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.catalina.ha.context;

import org.apache.catalina.core.StandardContext;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.ha.CatalinaCluster;
import org.apache.catalina.tribes.tipis.ReplicatedMap;
import org.apache.catalina.tribes.Channel;
import org.apache.catalina.Loader;
import org.apache.catalina.core.ApplicationContext;
import org.apache.catalina.Globals;
import javax.servlet.ServletContext;
import java.util.AbstractMap;
import org.apache.catalina.tribes.tipis.AbstractReplicatedMap;
import java.util.ArrayList;
import java.util.Iterator;
import javax.servlet.ServletContextAttributeListener;
import javax.servlet.ServletContextAttributeEvent;
import org.apache.catalina.LifecycleEvent;
import org.apache.catalina.LifecycleListener;
import java.util.Enumeration;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.catalina.util.Enumerator;
import org.apache.catalina.tribes.tipis.AbstractReplicatedMap.MapOwner;
import org.apache.catalina.ha.session.DeltaSession;

/**
 * @author Filip Hanik
 * @version 1.0
 */
public class ReplicatedContext extends StandardContext implements LifecycleListener,MapOwner {
    private int mapSendOptions = Channel.SEND_OPTIONS_DEFAULT;
    public static org.apache.juli.logging.Log log = org.apache.juli.logging.LogFactory.getLog( ReplicatedContext.class );
    protected boolean startComplete = false;
    protected static long DEFAULT_REPL_TIMEOUT = 15000;//15 seconds
    
    public void lifecycleEvent(LifecycleEvent event) {
        if ( event.getType() == AFTER_START_EVENT ) 
            startComplete = true;
    }

    public synchronized void start() throws LifecycleException {
        if ( this.started ) return;
        super.addLifecycleListener(this);            
        try {
            CatalinaCluster catclust = (CatalinaCluster)this.getCluster();
            if (this.context == null) this.context = new ReplApplContext(this.getBasePath(), this);
            if ( catclust != null ) {
                ReplicatedMap map = new ReplicatedMap(this,catclust.getChannel(),DEFAULT_REPL_TIMEOUT,
                                                      getName(),getClassLoaders());
                map.setChannelSendOptions(mapSendOptions);
                ((ReplApplContext)this.context).setAttributeMap(map);
                if (getAltDDName() != null) context.setAttribute(Globals.ALT_DD_ATTR, getAltDDName());
            }
            super.start();
        }  catch ( Exception x ) {
            log.error("Unable to start ReplicatedContext",x);
            throw new LifecycleException("Failed to start ReplicatedContext",x);
        }
    }
    
    public synchronized void stop() throws LifecycleException
    {
        ReplicatedMap map = (ReplicatedMap)((ReplApplContext)this.context).getAttributeMap();
        if ( map!=null ) {
            map.breakdown();
        }
        if ( !this.started ) return;
        try {
            super.lifecycle.removeLifecycleListener(this);
        } catch ( Exception x ){
            log.error("Unable to stop ReplicatedContext",x);
            throw new LifecycleException("Failed to stop ReplicatedContext",x);
        } finally {
            this.startComplete = false;
            super.stop();
        }
        

    }


    public void setMapSendOptions(int mapSendOptions) {
        this.mapSendOptions = mapSendOptions;
    }

    public int getMapSendOptions() {
        return mapSendOptions;
    }
    
    public ClassLoader[] getClassLoaders() {
        Loader loader = null;
        ClassLoader classLoader = null;
        loader = this.getLoader();
        if (loader != null) classLoader = loader.getClassLoader();
        if ( classLoader == null ) classLoader = Thread.currentThread().getContextClassLoader();
        if ( classLoader == Thread.currentThread().getContextClassLoader() ) {
            return new ClassLoader[] {classLoader};
        } else {
            return new ClassLoader[] {classLoader,Thread.currentThread().getContextClassLoader()};
        }
    }
    
    public ServletContext getServletContext() {
        if (context == null) {
            context = new ReplApplContext(getBasePath(), this);
            if (getAltDDName() != null)
                context.setAttribute(Globals.ALT_DD_ATTR,getAltDDName());
        }

        return ((ReplApplContext)context).getFacade();

    }

    
    protected static class ReplApplContext extends ApplicationContext {
        protected ConcurrentHashMap tomcatAttributes = new ConcurrentHashMap();
        
        public ReplApplContext(String basePath, ReplicatedContext context) {
            super(basePath,context);
        }
        
        protected ReplicatedContext getParent() {
            return (ReplicatedContext)getContext();
        }
        
        protected ServletContext getFacade() {
             return super.getFacade();
        }
        
        public AbstractMap getAttributeMap() {
            return (AbstractMap)this.attributes;
        }
        public void setAttributeMap(AbstractMap map) {
            this.attributes = map;
        }
        
        public void removeAttribute(String name) {
            tomcatAttributes.remove(name);
            //do nothing
            super.removeAttribute(name);
        }
        
        public void setAttribute(String name, Object value) {
            if ( (!getParent().startComplete) || "org.apache.jasper.runtime.JspApplicationContextImpl".equals(name) ){
                tomcatAttributes.put(name,value);
            } else
                super.setAttribute(name,value);
        }
        
        public Object getAttribute(String name) {
            if (tomcatAttributes.containsKey(name) )
                return tomcatAttributes.get(name);
            else 
                return super.getAttribute(name);
        }
        
        public Enumeration getAttributeNames() {
            return new MultiEnumeration(new Enumeration[] {super.getAttributeNames(),new Enumerator(tomcatAttributes.keySet(), true)});
        }
        
    }

    protected static class MultiEnumeration implements Enumeration {
        Enumeration[] e=null;
        public MultiEnumeration(Enumeration[] lists) {
            e = lists;
        }
        public boolean hasMoreElements() {
            for ( int i=0; i<e.length; i++ ) {
                if ( e[i].hasMoreElements() ) return true;
            }
            return false;
        }
        public Object nextElement() {
            for ( int i=0; i<e.length; i++ ) {
                if ( e[i].hasMoreElements() ) return e[i].nextElement();
            }
            return null;

        }
    }
    
    public void objectMadePrimay(Object key, Object value) {
        //noop
    }


}

Other Tomcat examples (source code examples)

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

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