JFinal 中的cron4j定时插件

1、下载cron4j的jar包，并放入classpath

http://www.sauronsoftware.it/projects/cron4j/download.php

2、编写Cron4jPlugin.java

package com.welicai.app.common.plugin;

import it.sauronsoftware.cron4j.InvalidPatternException;
import it.sauronsoftware.cron4j.Scheduler;

import java.io.IOException;
import java.io.InputStream;
import java.util.Date;
import java.util.Enumeration;
import java.util.Properties;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.jfinal.plugin.IPlugin;
import com.welicai.app.test.Testjob;

public class Cron4jPlugin implements IPlugin {

	private Logger logger = LoggerFactory.getLogger(getClass());
	private Scheduler scheduler = null;
	private String config = "job.properties";
	private Properties properties;

	public Cron4jPlugin(String config) {
		this.config = config;
	}

	public Cron4jPlugin() {

	}

	@SuppressWarnings({ "rawtypes"})
	public boolean start() {
		scheduler = new Scheduler();
		loadProperties();
		Enumeration enums = properties.keys();
		while (enums.hasMoreElements()) {
			String key = enums.nextElement() + "";
			if (!key.endsWith("job")) {
				continue;
			}
			String cronKey = key.substring(0, key.indexOf("job")) + "cron";
			String enable = key.substring(0, key.indexOf("job")) + "enable";
			if (isDisableJob(enable)) {
				continue;
			}
			String jobClassName = properties.get(key) + "";
			String jobCronExp = properties.getProperty(cronKey) + "";
			Class clazz;
			try {
				clazz = Class.forName(jobClassName);
			} catch (ClassNotFoundException e) {
				throw new RuntimeException(e);
			}
			try {

				scheduler.schedule(jobCronExp, (Runnable) clazz.newInstance());
			} catch (InvalidPatternException e) {
				throw new RuntimeException(e);
			} catch (InstantiationException e) {
				throw new RuntimeException(e);
			} catch (IllegalAccessException e) {
				throw new RuntimeException(e);
			}
			scheduler.start();
			logger.info(jobCronExp + " has been scheduled to run at: " + new Date()
					+ " and repeat based on expression: "
					);
		}
		return true;
	}

	private boolean isDisableJob(String enable) {
		return Boolean.valueOf(properties.get(enable) + "") == false;
	}

	private void loadProperties() {
		properties = new Properties();
		InputStream is = Cron4jPlugin.class.getClassLoader()
				.getResourceAsStream(config);
		try {
			properties.load(is);
		} catch (IOException e) {
			throw new RuntimeException(e);
		}
	}

	public boolean stop() {
		scheduler.stop();
		return true;
	}

	public static void main(String[] args) throws InterruptedException {
		 Cron4jPlugin plugin = new Cron4jPlugin();
		 plugin.start();
		 System.out.println("执行成功！！！");
		 Thread.sleep(5000);
		// plugin.stop();
	}

}

3、创建一个定时任务类（必须实现Runnable接口）

public class Testjob implements Runnable {

	public void run() {
	    System.out.println("Current system time: " + new Date());
	    System.out.println("Another minute ticked away...");
	}

}

4、在classpath下加入job.properties，然后配置上刚才创建的任务类（1分钟执行一次）

UpdateOrderStatusJob.job=com.welicai.app.test.Testjob
UpdateOrderStatusJob.cron=*/1 * * * *
UpdateOrderStatusJob.enable=true

5、把Cron4jPlugin加入jfinal的核心配置类configPlugin方法

/**
	 * 配置插件
	 */
	public void configPlugin( Plugins me ) {

		// 配置C3p0数据库连接池插件
	    C3p0Plugin c3p0Plugin = new C3p0Plugin( getProperty("url"), getProperty("user"), getProperty("pwd") );
	    me.add( c3p0Plugin );

	    // 配置ActiveRecord插件
	    ActiveRecordPlugin arp = new ActiveRecordPlugin( c3p0Plugin );
	    arp.setShowSql( Boolean.valueOf( getProperty("showSql") ) );
	    me.add( arp );
	    // 配置Cron4jPlugin插件
               me.add(new Cron4jPlugin());
	}

6、启动项目试一下吧(注意：cron4j只能精确到分，不能到秒，但是应该够用了，时间语法同Linux的crontab)