bytebuddy-替换类实现
1.依赖
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| dependencies {
implementation group: 'net.bytebuddy', name: 'byte-buddy', version: '1.11.8'
implementation group: 'net.bytebuddy', name: 'byte-buddy-agent', version: '1.11.8'
}
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2.测试类被替换类
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| package org.coral.jcode.simple.bytebuddy.reload;
public class Log {
public static void log(String a) {
System.out.println("Log: " + a);
}
}
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3.测试类替换目的类
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| package org.coral.jcode.simple.bytebuddy.reload;
public class Log4j {
/**
* 注意代理类要和原实现类的方法声明保持一致
* @param a
*/
public static void log(String a) {
System.err.println("Log4j: " + a);
}
}
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4.测试验证类
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| package org.coral.jcode.simple.bytebuddy.reload;
import net.bytebuddy.ByteBuddy;
import net.bytebuddy.agent.ByteBuddyAgent;
import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
import net.bytebuddy.implementation.MethodDelegation;
import net.bytebuddy.matcher.ElementMatchers;
public class LogMain {
public static void main(String[] args) {
// 替换
ByteBuddyAgent.install();
new ByteBuddy().redefine(Log.class)
.method(ElementMatchers.named("log"))
.intercept(MethodDelegation.to(Log4j.class))
.make()
.load(Thread.currentThread().getContextClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
// 调用
Log.log("hello");
}
}
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5.参考
https://houbb.github.io/2019/10/30/bytecode-byte-buddy-02-replace
