重写to String(）方法

柔光的暖阳◎ 2022-04-15 04:59 178阅读 0赞

to String()方法返回一个对象的字符串表示：

1.单个对象重写to String()方法：

例：

public class Car {
    
    	private String name;
    	private Double price;
    	
            //自己重写的toString()方法
    	/*public String toString(){
    		return "车名:"+name+"\n价格:"+price;
    	}*/
    
            //通过Eclipse直接快捷重新的toString()方法
    	@Override
    	public String toString() {
    		return "Car [name=" + name + ", price=" + price + "]";
    	}
    
    
            public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    	public double getPrice() {
    		return price;
    	}
    	public void setPrice(double price) {
    		this.price = price;
    	}

通过main方法进行测试:

public class CarDemo {
    
      public static void main(String[] args) {
        Car car=new Car();
        car.setName("布加迪威龙");
        car.setPrice(99999d);
    
        //对象重写toString()则输出指定的字符串
        System.out.println(car);

2.多个对象重写toString()方法，通过使用可变字符串StringBuilder来建立

import java.awt.Color;
    
    public class Cat {
        private String name;
        private int age;
        private double weight;
        private Color color;
        
        public Cat(String name, int age, double weight, Color color) {
            this.name = name;
            this.age = age;
            this.weight = weight;
            this.color = color;
        }
        
        @Override
        public String toString() {
            StringBuilder sb = new StringBuilder();
            sb.append("名字：" + name + "\n");
            sb.append("年龄：" + age + "\n");
            sb.append("重量：" + weight + "\n");
            sb.append("颜色：" + color + "\n");
            return sb.toString();
        }
    }

通过Test类Main方法进行验证

import java.awt.Color;
    
    public class Test {
        public static void main(String[] args) {
            Cat cat1 = new Cat("Java", 12, 21, Color.BLACK);
            Cat cat2 = new Cat("C++", 12, 21, Color.WHITE);
            Cat cat3 = new Cat("Java", 12, 21, Color.BLACK);
            System.out.println("猫咪1号：" + cat1);
            System.out.println("猫咪2号：" + cat2);
            System.out.println("猫咪3号：" + cat3);
        }
    }