Arthas实现代码热更新

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package com.tiandy.testdemo;
@SpringBootApplication
public class TestDemoApplication {

    public static void main(String[] args) throws InterruptedException {
        SpringApplication.run(TestDemoApplication.class, args);
        all();

    }
    public static void all() throws InterruptedException {
        int space = 2;
        do {
            add(space);
        } while (true);
    }

    static int i = 0;

    public static void add(int space) throws InterruptedException {
        TimeUnit.SECONDS.sleep(1);
        System.out.println("★★★★★★---》" + (i += space));
    }

}

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## 找到项目进程号
ps -ef | grep TestDemo
## 启动arthas 
#/opt/apache-tomcat/jre/bin/java 是我java的安装位置
#/usr/arthas/arthas-boot.jar 是arthas的安装位置
/opt/apache-tomcat/jre/bin/java -jar /usr/arthas/arthas-boot.jar 21932
## 通过jad反编译代码，把它保存到另一个.java 文件中
## 注意--source-only 要进跟在jad后面
jad  --source-only  com.tiandy.testdemo.TestDemoApplication > /var/TestDemoApplication.java
## 再开一窗口编辑/var/TestDemoApplication.java，修改代码
vim /var/TestDemoApplication.java
## 查找这个类的类加载器，编译时不指定类加载器可能会失败
sc -d *TestDemoApplication | grep classLoaderHash
## 编译为class文件
mc -c de5a126b /var/TestDemoApplication.java -d /var/TestDemoApplication.class
## 加载外部的class文件，实现热更新
redefine -c de5a126b /var/com/tiandy/testdemo/TestDemoApplication.class

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public static void all() throws InterruptedException {
        int space = 3;
        do {
            add(space);
        } while (true);
    }

    static int i = 0;

    public static void add(int space) throws InterruptedException {
        System.out.println("★★★★★★---》"+"111111111");
        TimeUnit.SECONDS.sleep(1);
        System.out.println("★★★★★★---》" + (i += space));
    }

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base64 < Test.class > result.txt

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base64 -d < result.txt > Test.class