ArrayList练习2

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将自定义对象作为元素存到ArrayList集合中，并去除重复元素

比如：存人对象，同姓名同年龄，视为同一个人。为重复元素

思路：

1，对人描述，将数据封装进人对象

2，定义容器，将人存入

3，取出

List集合判断元素是否相同，依据的是元素的equals方法

import java.util.*;class Person{    private String name;    private int age;    Person(String name,int age)    {        this.name = name;        this.age = age;    }    public boolean equals(Object obj)    {        if(!(obj instanceof Person))            return false;        Person p = (Person)obj;        System.out.println(this.name+"....."+p.name);                 return this.name.equals(p.name) && this.age == p.age;    }    public String getName()    {        return name;    }    public int getAge()    {        return age;    }}class ArrayListTest2{    public static void sop(Object obj)    {        System.out.println(obj);    }    public static void main(String[] args)    {        ArrayList al = new ArrayList();        al.add(new Person("list01",30));        al.add(new Person("list02",32));        al.add(new Person("list02",32));        al.add(new Person("list03",33));        al.add(new Person("list04",35));        al.add(new Person("list04",35));        al = singleElement(al);                 Iterator it = al.iterator();                 while(it.hasNext())        {            Person p = (Person)it.next();            sop(p.getName()+"::"+p.getAge());        }    }         public static ArrayList singleElement(ArrayList al)    {        //定义一个临时容器        ArrayList newAl = new ArrayList();                 Iterator it = al.iterator();                 while(it.hasNext())        {            Object obj = it.next();                         if(!(newAl.contains(obj)))                newAl.add(obj);        }                 return newAl;    }}

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