迭代器模式（iterator）中介者模式模式（Mediator）——尚学堂笔记

1. 迭代器模式（iterator）

package com.bjsxt.iterator;


/**
 *  自定义的迭代器接口
 * @author Administrator
 *
 */
public interface MyIterator {
	void first();	//将游标指向第一个元素
	void next();	//将游标指向下一个元素
	boolean hasNext();//判断是否存在下一个元素
	
	boolean isFirst();
	boolean isLast();
	
	Object getCurrentObj();  //获取当前游标指向的对象
}

package com.bjsxt.iterator;

import java.util.ArrayList;
import java.util.List;

/**
 * 自定义的聚合类
 * @author Administrator
 *
 */
public class ConcreteMyAggregate {
	private List<Object> list = new ArrayList<Object>();

	public void addObject(Object obj){
		this.list.add(obj);
	}
	public void removeObject(Object obj){
		this.list.remove(obj);
	}

	public List<Object> getList() {
		return list;
	}

	public void setList(List<Object> list) {
		this.list = list;
	}
	
	
	//获得迭代器
	public MyIterator  createIterator(){
		return new ConcreteIterator();
	}
	
	
	
	//使用内部类定义迭代器，可以直接使用外部类的属性
	private class ConcreteIterator implements MyIterator {

		private int cursor;  //定义游标用于记录遍历时的位置
		
		@Override
		public void first() {
			cursor = 0;
		}

		@Override
		public Object getCurrentObj() {
			return list.get(cursor);
		}

		@Override
		public boolean hasNext() {
			if(cursor<list.size()-1){
				return true;
			}
			return false;
		}

		@Override
		public boolean isFirst() {
			return cursor==0?true:false;
		}

		@Override
		public boolean isLast() {
			return cursor==(list.size()-1)?true:false;
		}

		@Override
		public void next() {
			if(cursor<list.size()){
				cursor++;
			}
		}
		
	}
		
	
}

package com.bjsxt.iterator;

public class Client {
	
	public static void main(String[] args) {
		ConcreteMyAggregate cma = new ConcreteMyAggregate();
		cma.addObject("aa");
		cma.addObject("bb");
		cma.addObject("cc");
		
		MyIterator iter = cma.createIterator();
		while(iter.hasNext()){
			System.out.println(iter.getCurrentObj());
			iter.next();
		}
		
	}
}

2. 中介者模式模式（Mediator）

package com.bjsxt.mediator;
//中介者接口
public interface Mediator {
	
	void register(String dname,Department d);  //注册
	
	void command(String dname);//命令
	
}

package com.bjsxt.mediator;

//同事类的接口
public interface Department {
	void selfAction(); //做本部门的事情
	void outAction();  //向总经理发出申请
}

package com.bjsxt.mediator;

import java.util.HashMap;
import java.util.Map;

public class President implements Mediator {
	
	private Map<String,Department> map = new HashMap<String , Department>();
	
	@Override
	public void command(String dname) {
		map.get(dname).selfAction();  //命令名为dname的Department做本部门的事情
	}

	@Override
	public void register(String dname, Department d) {  //将名为dname的Department加入map中，即为注册了
		map.put(dname, d);
	}

}

package com.bjsxt.mediator;

public class Development implements Department {

	private Mediator m;  //持有中介者(总经理)的引用
	
	public Development(Mediator m) {
		super();
		this.m = m;
		m.register("development", this);
	}

	@Override
	public void outAction() {
		System.out.println("汇报工作！没钱了，需要资金支持！");
	}

	@Override
	public void selfAction() {
		System.out.println("专心科研，开发项目！");
	}

}

package com.bjsxt.mediator;

public class Finacial implements Department {

	private Mediator m;  //持有中介者(总经理)的引用
	
	public Finacial(Mediator m) {
		super();
		this.m = m;
		m.register("finacial", this);
	}

	@Override
	public void outAction() {
		System.out.println("汇报工作！钱太多了！怎么花?");
	}

	@Override
	public void selfAction() {
		System.out.println("数钱！");
	}

}

package com.bjsxt.mediator;

public class Market implements Department {

	private Mediator m;  //持有中介者(总经理)的引用
	
	public Market(Mediator m) {
		super();
		this.m = m;
		m.register("market", this);
	}

	@Override
	public void outAction() {
		System.out.println("汇报工作！项目承接的进度，需要资金支持！");
		
		m.command("finacial");   //Market与Finacial	交互，是通过中介者Mediator实现的
	}

	@Override
	public void selfAction() {
		System.out.println("跑去接项目！");
	}

}

package com.bjsxt.mediator;

public class Client {
	public static void main(String[] args) {
		Mediator m = new President();
		
		Market   market = new Market(m);
		Development devp = new Development(m);
		Finacial f = new Finacial(m);
		
		market.selfAction();
		market.outAction();
		
	}
}