/*
* 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.
*
*/
/*
* Previously Copyright (c) 2001-2004 James House
*/
package org.quartz.jobs;
import java.io.File;
import org.quartz.JobDataMap;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.quartz.SchedulerContext;
import org.quartz.SchedulerException;
import org.quartz.StatefulJob;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* Inspects a file and compares whether it's "last modified date" has changed
* since the last time it was inspected. If the file has been updated, the
* job invokes a "call-back" method on an identified
* <code>FileScanListener</code> that can be found in the
* <code>SchedulerContext</code>.
*
* @author jhouse
* @see org.quartz.jobs.FileScanListener
*/
public class FileScanJob implements StatefulJob {
public static String FILE_NAME = "FILE_NAME";
public static String FILE_SCAN_LISTENER_NAME = "FILE_SCAN_LISTENER_NAME";
private static String LAST_MODIFIED_TIME = "LAST_MODIFIED_TIME";
public FileScanJob() {
}
/**
* @see org.quartz.Job#execute(org.quartz.JobExecutionContext)
*/
public void execute(JobExecutionContext context) throws JobExecutionException {
Log log = LogFactory.getLog(getClass());
JobDataMap data = context.getJobDetail().getJobDataMap();
SchedulerContext schedCtxt = null;
try {
schedCtxt = context.getScheduler().getContext();
} catch (SchedulerException e) {
throw new JobExecutionException("Error obtaining scheduler context.", e, false);
}
String fileName = data.getString(FILE_NAME);
String listenerName = data.getString(FILE_SCAN_LISTENER_NAME);
if(fileName == null)
throw new JobExecutionException("Required parameter '" +
FILE_NAME + "' not found in JobDataMap");
if(listenerName == null)
throw new JobExecutionException("Required parameter '" +
FILE_SCAN_LISTENER_NAME + "' not found in JobDataMap");
FileScanListener listener = (FileScanListener)schedCtxt.get(listenerName);
if(listener == null)
throw new JobExecutionException("FileScanListener named '" +
listenerName + "' not found in SchedulerContext");
long lastDate = -1;
if(data.containsKey(LAST_MODIFIED_TIME))
lastDate = data.getLong(LAST_MODIFIED_TIME);
long newDate = getLastModifiedDate(fileName);
if(newDate < 0) {
log.warn("File '"+fileName+"' does not exist.");
return;
}
if(lastDate > 0 && (newDate != lastDate)) {
// notify call back...
log.info("File '"+fileName+"' updated, notifying listener.");
listener.fileUpdated(fileName);
}
else
log.debug("File '"+fileName+"' unchanged.");
data.put(LAST_MODIFIED_TIME, newDate);
}
protected long getLastModifiedDate(String fileName) {
File file = new File(fileName);
if(!file.exists()) {
return -1;
}
else {
return file.lastModified();
}
}
}