TestArrayList

package com.jh;
import java.util.*;
class Studental
{
private String name;
private int age;
public Studental(){}
public Studental(String name,int age)
{
this.name=name;
this.age=age;
}
public String toString() //如果重写ToString方法，返回的只是对象，地址
{
return name+","+age;
}
public boolean equals(Object obj)
{
if(!(obj instanceof Studental)) 
{
throw new RuntimeException("类型错误");
}
Studental stu=(Studental)obj;
return this.age==stu.age && this.name.equals(this.name);
}
}
public class TestArrayList {
public static void main(String[] args) { 
ArrayList list=new ArrayList();
list.add(new Studental("lili",23));
list.add(new Studental("yoti",27));
list.add(new Studental("mingming",30));
list.add(new Studental("yoti",27));
// sop(list); //[lili,23, yoti,27, mingming,30, yoti,27]

ArrayList arrList=quChu(list);
sop(arrList);//[lili,23, yoti,27, mingming,30]


}



//姓名年龄相同的认为同一个对象，去掉姓名年龄相同的，
public static ArrayList quChu(ArrayList list)
{
ArrayList list2=new ArrayList();
for(int i=0;i<list.size();i++)
{
Object obj=list.get(i);
if(!list2.contains(obj))
{
list2.add(obj);
}
}
return list2;
}

//输出
public static void sop(Object obj)
{
System.out.println(obj);
}
}