java比较器Comparator 使用

package cn.stat.p5.person.demo;

public class PresonDemo implements Comparable  {

private String name;
private int age;

/**
* @param args
*/

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public void outPrint()
{

System.out.println(this.age+".."+this.name);
}
public PresonDemo(String name, int age) {

this.name = name;
this.age = age;
}
//TreeSet();为空时，实列类内部比较器
@Override
public int compareTo(Object o) {
// TODO Auto-generated method stub
PresonDemo p=(PresonDemo)o;
if(p.age<this.age)
return 1;
if(p.age>this.age)
return-1;
return 0;
}

}

/**
* 根据名子比较返回顺序
*/
package cn.stat.p6.arraylist.demo;

import java.util.Comparator;

import cn.stat.p5.person.demo.PresonDemo;

/**
* @author Administrator
*
*/
public class CompartorbyName implements Comparator {

/* (non-Javadoc)
* @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
*/
@Override
public int compare(Object o1, Object o2) {
// TODO Auto-generated method stub
PresonDemo p1=(PresonDemo)o1;
PresonDemo p2=(PresonDemo)o2;
int temp=p1.getName().compareTo(p2.getName());
return temp==0?p1.getAge()-p2.getAge():temp;
}

}

package cn.stat.p6.arraylist.demo;
import cn.stat.p5.person.demo.PresonDemo;
import java.util.Iterator;
import java.util.TreeSet;
import java.util.ArrayList;

public class TreeSetDemo {

public static void main(String[] args) {
TreeSet ts=new TreeSet(new CompartorbyName()); //比较器

ts.add(new PresonDemo("list1",2));
ts.add(new PresonDemo("list9",2));
ts.add(new PresonDemo("list7",2));
ts.add(new PresonDemo("list4",2));
ts.add(new PresonDemo("list5",2));
Iterator<PresonDemo> it=ts.iterator();
while(it.hasNext())
{
PresonDemo p=(PresonDemo)it.next();
System.out.println(p.getName()+"  "+p.getAge());

}
}
}