java入门第二季–继承–Object类

Object类

toString()方法

代码
/javaDemo3/src/com/imooc/Animal.java
package com.imooc;

public class Animal {
public Animal() {

}
}

/javaDemo3/src/com/imooc/Dog.java
package com.imooc;
import java.util.*;
public class Dog extends Animal {

public Dog() {
System.out.println(“Dog类执行了” );
}

}

/javaDemo3/src/com/imooc/Initail.java
package com.imooc;

public class Initail {

public static void main(String[] args) {
// TODO Auto-generated method stub
Dog dog = new Dog();
System.out.println(dog);
}

}

重写toString()方法
/javaDemo3/src/com/imooc/Dog.java右键 -> source -> genenor toString]
package com.imooc;
import java.util.*;
public class Dog extends Animal {

public Dog() {
System.out.println(“Dog类执行了” );
}

public String toString() {
return “Dog [age=” + age + “]”;
}

}