this小案例

public class Son extends Parent {
    
    public String name="jack";
    
    public void init(){
        super.init();
        System.out.println(this.name);
    }
    
    public static void main(String[] args) {
        Son son = new Son();
        son.init();  //init(son)
        System.out.println("## " + son.name);
        
        Parent p = new Son();
        System.out.println("** " + p.name);
        
    }

}

public class Parent {
    
    public String name="tom";

    public void init() {
        System.out.println(this.name);
    }
    
}
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public class Parent {

    public void init() {
        System.out.println("1 init parent");
        this.demo();
    }
    
    public void demo() {
        System.out.println("2 demo parent");
    }

}

public class Son extends Parent {
    
    public void init(){
        super.init();
        System.out.println("3 init son");
        this.demo();
    }
    
    public void demo() {
        System.out.println("4 demo Son");
    }
    
    public static void main(String[] args) {
        //当前运行类 Son
        Son son = new Son();
        son.init();  //init(son)
    }

}