/*  * 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);        }    }}