Java代码块

package com.yyx.pratice;

class Root {
    static {
        System.out.println("Root的静态初始化块");
    }
    {
        System.out.println("Root的普通初始化块");
    }

    public Root() {
        System.out.println("Root的无参数的构造器");
    }
}

class Mid extends Root {
    static {
        System.out.println("Mid的静态初始化块");
    }
    {
        System.out.println("Mid的普通初始化块");
    }

    public Mid() {
        System.out.println("Mid的无参数的构造器");
    }

    public Mid(String msg) {
        // 通过this调用同一类中重载的构造器
        this();
        System.out.println("Mid的带参数构造器，其参数值：" + msg);
    }
}

class Leaf extends Mid {
    static {
        System.out.println("Leaf的静态初始化块");
    }
    {
        System.out.println("Leaf的普通初始化块");
    }

    public Leaf() {
        // 通过super调用父类中有一个字符串参数的构造器
        super("尚硅谷");
        System.out.println("执行Leaf的构造器");
    }
}

public class TestLeaf {
    public static void main(String[] args) {
        new Leaf();
        System.out.println();
        new Leaf();
    }
}