org.apache.hms.common.util.MulticastDNS.java Source code

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Here is the source code for org.apache.hms.common.util.MulticastDNS.java

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/*
 * 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.hms.common.util;

import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Hashtable;

import javax.jmdns.JmDNS;
import javax.jmdns.ServiceInfo;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class MulticastDNS {
    private static Log LOG = LogFactory.getLog(MulticastDNS.class);
    public static JmDNS jmdns;
    private InetAddress addr;
    private String svcType = "_zookeeper._tcp.local.";
    private String svcName;
    private int svcPort = 2181;
    private Hashtable<String, String> settings;

    public MulticastDNS() throws UnknownHostException {
        super();
        InetAddress addr = InetAddress.getLocalHost();
        String hostname = addr.getHostName();
        if (hostname.indexOf('.') > 0) {
            hostname = hostname.substring(0, hostname.indexOf('.'));
        }
        svcName = hostname;
        settings = new Hashtable<String, String>();
        settings.put("host", svcName);
        settings.put("port", new Integer(svcPort).toString());
    }

    public MulticastDNS(String svcType, int svcPort) throws UnknownHostException {
        this();
        this.svcType = svcType;
        this.svcPort = svcPort;
    }

    public MulticastDNS(InetAddress addr, String svcType, int svcPort) throws UnknownHostException {
        this();
        this.addr = addr;
        this.svcType = svcType;
        this.svcPort = svcPort;
    }

    protected void handleRegisterCommand() throws IOException {
        if (jmdns == null) {
            if (addr != null) {
                jmdns = JmDNS.create(this.addr);
            } else {
                jmdns = JmDNS.create();
            }
        }
        ServiceInfo svcInfo = ServiceInfo.create(svcType, svcName, svcPort, 1, 1, settings);
        try {
            this.jmdns.registerService(svcInfo);
            LOG.info("Registered service '" + svcName + "' as: " + svcInfo);
        } catch (IOException e) {
            LOG.error("Failed to register service '" + svcName + "'");
        }
    }

    protected void handleUnregisterCommand() {
        this.jmdns.unregisterAllServices();
        try {
            this.jmdns.close();
        } catch (IOException e) {
            LOG.error(ExceptionUtil.getStackTrace(e));
        }
    }

}