QuartzClusterableJob.java

package org.springside.examples.showcase.schedule;

import java.util.Map;

import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.scheduling.quartz.QuartzJobBean;
import org.springside.examples.showcase.common.service.AccountManager;

/**
 * 被Spring的Quartz JobDetailBean定时执行的Job类, 支持持久化到数据库实现Quartz集群.
 * 
 * 因为需要被持久化, 不能有用XXManager等不能被持久化的成员变量, 
 * 只能在每次调度时从QuartzJobBean注入的applicationContext中动态取出.
 */
public class QuartzClusterableJob extends QuartzJobBean {

	private static Logger logger = LoggerFactory.getLogger(QuartzClusterableJob.class);

	private ApplicationContext applicationContext;

	/**
	 * 从SchedulerFactoryBean注入的applicationContext.
	 */
	public void setApplicationContext(ApplicationContext applicationContext) {
		this.applicationContext = applicationContext;
	}

	/**
	 * 定时打印当前用户数到日志.
	 */
	@SuppressWarnings("unchecked")
	@Override
	protected void executeInternal(JobExecutionContext ctx) throws JobExecutionException {
		AccountManager accountManager = applicationContext.getBean(AccountManager.class);
		Map config = (Map) applicationContext.getBean("timerJobConfig");

		long userCount = accountManager.getUserCount();
		String nodeName = (String) config.get("nodeName");

		logger.info("There are {} user in database, print by {}'s job.", userCount, nodeName);
	}
}