mcastservice.java

精通tomcat书籍原代码,希望大家共同学习

/*
 * Copyright 1999,2004-2005 The Apache Software Foundation.
 * 
 * Licensed 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.cluster.mcast;

import java.util.Properties;

import javax.management.MBeanServer;
import javax.management.ObjectName;

import org.apache.catalina.Cluster;
import org.apache.catalina.Container;
import org.apache.catalina.cluster.Member;
import org.apache.catalina.cluster.MembershipListener;
import org.apache.catalina.cluster.MembershipService;
import org.apache.catalina.cluster.tcp.SimpleTcpCluster;
import org.apache.catalina.core.StandardHost;
import org.apache.catalina.util.StringManager;
import org.apache.commons.modeler.Registry;

/**
 * A <b>membership</b> implementation using simple multicast.
 * This is the representation of a multicast membership service.
 * This class is responsible for maintaining a list of active cluster nodes in the cluster.
 * If a node fails to send out a heartbeat, the node will be dismissed.
 *
 * FIXME i18n messages
 * 
 * @author Peter Rossbach
 * @author Filip Hanik
 * @version $Revision: 380229 $, $Date: 2006-02-23 16:28:29 -0500 (Thu, 23 Feb 2006) $
 */


public class McastService implements MembershipService,MembershipListener {

    private static org.apache.commons.logging.Log log =
        org.apache.commons.logging.LogFactory.getLog( McastService.class );

    /**
     * The string manager for this package.
     */
    protected StringManager sm = StringManager.getManager(Constants.Package);

    /**
     * The descriptive information about this implementation.
     */
    private static final String info = "McastService/2.1";

    /**
     * The implementation specific properties
     */
    protected Properties properties = new Properties();
    /**
     * A handle to the actual low level implementation
     */
    protected McastServiceImpl impl;
    /**
     * A membership listener delegate (should be the cluster :)
     */
    protected MembershipListener listener;
    /**
     * The local member
     */
    protected McastMember localMember ;
    private int mcastSoTimeout;
    private int mcastTTL;

    /**
     * my cluster
     */
    private SimpleTcpCluster cluster;

    /**
     * Transmitter Mbean name
     */
    private ObjectName objectName;

    private Registry registry;

    /**
     * Create a membership service.
     */
    public McastService() {
        properties.setProperty("mcastClusterDomain", "catalina");
    }

    /**
     * Return descriptive information about this implementation and the
     * corresponding version number, in the format
     * <code>&lt;description&gt;/&lt;version&gt;</code>.
     */
    public String getInfo() {
        return (info);
    }
    
    /**
     * Transmitter ObjectName
     * 
     * @param name
     */
    public void setObjectName(ObjectName name) {
        objectName = name;
    }

    public ObjectName getObjectName() {
        return objectName;
    }

    /**
     *
     * @param properties
     * <BR/>All are required<BR />
     * 1. mcastPort - the port to listen to<BR>
     * 2. mcastAddress - the mcast group address<BR>
     * 3. mcastClusterDomain - the mcast cluster domain<BR>
     * 4. bindAddress - the bind address if any - only one that can be null<BR>
     * 5. memberDropTime - the time a member is gone before it is considered gone.<BR>
     * 6. msgFrequency - the frequency of sending messages<BR>
     * 7. tcpListenPort - the port this member listens to<BR>
     * 8. tcpListenHost - the bind address of this member<BR>
     * @exception java.lang.IllegalArgumentException if a property is missing.
     */
    public void setProperties(Properties properties) {
        hasProperty(properties,"mcastPort");
        hasProperty(properties,"mcastAddress");
        hasProperty(properties,"mcastClusterDomain");
        hasProperty(properties,"memberDropTime");
        hasProperty(properties,"msgFrequency");
        hasProperty(properties,"tcpListenPort");
        hasProperty(properties,"tcpListenHost");
        this.properties = properties;
    }

    /**
     * Return the properties, see setProperties
     */
    public Properties getProperties() {
        return properties;
    }

    /*
     * configured in cluster
     * 
     * @see org.apache.catalina.cluster.ClusterSender#setCatalinaCluster(org.apache.catalina.cluster.tcp.SimpleTcpCluster)
     */
    public void setCatalinaCluster(SimpleTcpCluster cluster) {
        this.cluster = cluster;

    }

    /**
     * Return the cluster for this membership service
     */
    public Cluster getCatalinaCluster() {
        return cluster ;
    }

    /**
     * Return the local member name
     */
    public String getLocalMemberName() {
        return localMember.toString() ;
    }
 
    /**
     * Return the local member
     */
    public Member getLocalMember() {
        localMember.setMemberAliveTime(System.currentTimeMillis()-impl.getServiceStartTime());
        return localMember;
    }
    
    /**
     * Sets the local member properties for broadcasting
     */
    public void setLocalMemberProperties(String listenHost, int listenPort) {
        properties.setProperty("tcpListenHost",listenHost);
        properties.setProperty("tcpListenPort",String.valueOf(listenPort));
    }
    
    public void setMcastAddr(String addr) {
        properties.setProperty("mcastAddress", addr);
    }

    public String getMcastAddr() {
        return properties.getProperty("mcastAddress");
    }

    public void setMcastBindAddress(String bindaddr) {
        properties.setProperty("mcastBindAddress", bindaddr);
    }

    public String getMcastBindAddress() {
        return properties.getProperty("mcastBindAddress");
    }

    public void setMcastClusterDomain(String clusterDomain) {
        properties.setProperty("mcastClusterDomain", clusterDomain);
    }

    public String getMcastClusterDomain() {
        return properties.getProperty("mcastClusterDomain");
    }

    public void setMcastPort(int port) {
        properties.setProperty("mcastPort", String.valueOf(port));
    }

    public int getMcastPort() {
        String p = properties.getProperty("mcastPort");
        return new Integer(p).intValue();
    }
    
    public void setMcastFrequency(long time) {
        properties.setProperty("msgFrequency", String.valueOf(time));
    }

    public long getMcastFrequency() {
        String p = properties.getProperty("msgFrequency");
        return new Long(p).longValue();
    }

    public void setMcastDropTime(long time) {
        properties.setProperty("memberDropTime", String.valueOf(time));
    }

    public long getMcastDropTime() {
        String p = properties.getProperty("memberDropTime");
        return new Long(p).longValue();
    }

    /**
     * Check if a required property is available.
     * @param properties The set of properties
     * @param name The property to check for
     */
    protected void hasProperty(Properties properties, String name){
        if ( properties.getProperty(name)==null) throw new IllegalArgumentException("Required property \""+name+"\" is missing.");