Java Instrumentation小结

实验代码参考 https://gitee.com/woopokyuk/instrumentation-test

字节码修改三要素

Agent类
Transformer类
目标测试类

注意事项

在POM中添加依赖

<dependency>
    <groupId>javassist</groupId>
    <artifactId>javassist</artifactId>
    <version>3.8.0.GA</version>
</dependency>

POM添加插件
插件需要单独下载

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-jar-plugin</artifactId>
    <version>2.2</version>
    <configuration>
        <archive>
            <manifestEntries>
                <Premain-Class>com.AopAgentTest</Premain-Class>
                <Boot-Class-Path>D:/Download/javassist-3.8.0.GA.jar</Boot-Class-Path>
            </manifestEntries>
        </archive>
    </configuration>
</plugin>

配置MF文件

Premain-Class: com.AopAgentTest
Agent-Class: com.AopAgentTest
Can-Redefine-Classes: true
Class-Path: D:/Download/javassist-3.8.0.GA.jar
Can-Retransform-Classes: true

最后通过执行

1	java -javaagent:D:\Projects\2022SEU\instrumentationTest\target\instrumentationTest.jar com.AopAgentTest

即可得到结果