JVM Initialization(初始化)阶段概述

ゞ浴缸里的玫瑰 2022-09-04 14:59 164阅读 0赞

# 一 点睛 #

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

![20210815110359741.png][]

口诀：由父及子，静态先行。

# 二 实战——初始化阶段基本测试 #

## 1 代码 ##

/**
    * 过程三：初始化阶段
    */
    public class InitializationTest {
        public static int id = 1;
        public static int number;
    
    
        static {
            number = 2;
            System.out.println("father static{}");
        }
    }

## 2 图解 ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 1][]

# 三 实战——由父及子 #

## 1 代码 ##

// 父类
    public class InitializationTest {
        public static int id = 1;
        public static int number;
    
    
        static {
            number = 2;
            System.out.println("father static{}");
        }
    }
    //  子类
    public class SubInitialization extends InitializationTest {
        static{
            number = 4;//number属性必须提前已经加载：一定会先加载父类。
            System.out.println("son static{}");
        }
    
        public static void main(String[] args) {
            System.out.println(number);
        }
    }

## 2 测试 ##

> father static\{\}
> 
> son static\{\}
> 
> 4

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[20210815110359741.png]: /images/20220829/f9eadfd92af944c58c62bbe94f178384.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 1]: /images/20220829/fdcd85416475491d9074af640fb76966.png