Exec.java

package com.alibaba.rocketmq.namesrv.sync;

/**
 * 
 * @author lansheng.zj@taobao.com
 *
 * @param <R> ����ֵ����
 * @param <T> ��������
 */
public abstract class Exec<R, T> {
	
	public void beforeExec(){}
	
	public abstract R doExec(T param) throws Exception;
	
	public void afterExec(R r){}
	
	public R exec(T param) throws Exception {
		beforeExec();
		R r = doExec(param);
		afterExec(r);
		return r;
	}
	
	
}