设计模式读书笔记之模版方法模式(Template)

//模版
package designpattern.template;
public abstract class Template {
private void step1(){
System.out.println("This is the first step.");
}
protected abstract void step2();
private void step3(){
System.out.println("This is the third step.");
}
public void process(){
step1();
step2();
step3();
}
}
//实现类
package designpattern.template;

public class Concrete extends Template{
protected void step2() {
System.out.println("This is the second step, it's implemented in sub class");
}
}
//上下文
package designpattern.template;
public class Context {
private Template t;
public Context(Template t){
this.t = t;
}
public void process(){
t.process();
}
//test case
public static void main(String[] args) {
Context c = new Context(new Concrete());
c.process();
}
}