hostnameinstanceidgenerator.java

来自「Quartz 是个开源的作业调度框架」· Java 代码 · 共 50 行

/* 
 * Copyright 2004-2005 OpenSymphony 
 * 
 * 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.quartz.simpl;

import java.net.InetAddress;

import org.quartz.SchedulerException;
import org.quartz.spi.InstanceIdGenerator;

/**
 * <p>
 * <code>InstanceIdGenerator</code> that names the scheduler instance using 
 * just the machine hostname.
 * </p>
 * 
 * <p>
 * This class is useful when you know that your scheduler instance will be the 
 * only one running on a particular machine.  Each time the scheduler is 
 * restarted, it will get the same instance id as long as the machine is not 
 * renamed.
 * </p>
 * 
 * @see InstanceIdGenerator
 * @see SimpleInstanceIdGenerator
 */
public class HostnameInstanceIdGenerator implements InstanceIdGenerator
{
    public String generateInstanceId() throws SchedulerException {
        try {
            return InetAddress.getLocalHost().getHostName();
        }
        catch (Exception e) {
            throw new SchedulerException("Couldn't get host name!", e);
        }
    }
}