toString()方法之使用

package com.aaa;

import java.util.ArrayList;
import java.util.Vector;

public class ToStringTest {
public static void main(String[] args) {
ArrayList<String> list=new ArrayList<String>();
list.add("aaa");
list.add("bbb");
list.add("ccc");
System.out.print(list);
// 打印结果为:[aaa, bbb, ccc]
Vector<String> vector=new Vector<String>();
vector.add("aaa");
vector.add("bbb");
vector.add("ccc");
System.out.println(vector);
// 打印结果为:[aaa, bbb, ccc]
Vector<Thing> things=new Vector<Thing>();
Thing thing1=new Thing(1, "aaa","one");
Thing thing2=new Thing(2, "bbb","two");
Thing thing3=new Thing(3, "ccc","three");
things.add(thing1);
things.add(thing2);
things.add(thing3);
System.out.println(things.toString());
// 类Thing没有toString方法之前,打印结果为[com.aaa.Thing@dd41677, com.aaa.Thing@5f0ee5b8, com.aaa.Thing@4b0bc3c9]
// 类Thing重写toString方法之后,打印结果为[aaa:one, bbb:two, ccc:three]
ArrayList<Thing> something=new ArrayList<Thing>();
something.add(thing1);
something.add(thing2);
something.add(thing3);
System.out.println(something);
// 类Thing没有toString方法之前,打印结果为[com.aaa.Thing@dd41677, com.aaa.Thing@5f0ee5b8, com.aaa.Thing@4b0bc3c9]
// 类Thing重写toString方法之后,打印结果为[aaa:one, bbb:two, ccc:three]
}
}
class Thing{
private int id;
private String name;
private String desc;

public Thing(int id, String name,String desc) {
super();
this.id = id;
this.name = name;
this.desc=desc;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
//重写Object的toString()方法
public String toString(){
return name+":"+desc;
}

}

原文地址:https://www.cnblogs.com/mubin/p/3528258.html