Skywalking git：

GitHub - apache/skywalking: APM, Application Performance Monitoring System

 集成入门：

10分钟3个步骤集成使用SkyWalking - 知乎

 下面自己学习了一下ByteBuddy的用法，实战了一下：

入门教程：

ByteBuddy入门教程 - 知乎

 这篇也不错：

一、基于Byte Buddy语法创建的第一个HelloWorld | 小傅哥 bugstack 虫洞栈

 下面直接上代码

Monitor项目是服务记录时间的一个非侵入性的jar

pom

<dependencies><!--解决字节码操作和Instrumentation API的复杂性--><dependency><groupId>net.bytebuddy</groupId><artifactId>byte-buddy</artifactId><version>1.9.2</version></dependency><dependency><groupId>net.bytebuddy</groupId><artifactId>byte-buddy-agent</artifactId><version>1.9.2</version></dependency></dependencies><build><plugins><plugin><artifactId>maven-assembly-plugin</artifactId><configuration><appendAssemblyId>false</appendAssemblyId><descriptorRefs><!--打包时加入依赖--><descriptorRef>jar-with-dependencies</descriptorRef></descriptorRefs><archive><!--自动生成/META-INF/MANIFEST.MF--><manifestEntries><Premain-Class>org.monitor.MonitorAgent</Premain-Class><Agent-Class>org.monitor.MonitorAgent</Agent-Class><Can-Redefine-Classes>true</Can-Redefine-Classes><Can-Retransform-Classes>true</Can-Retransform-Classes></manifestEntries></archive></configuration><executions><execution><id>make-assembly</id><phase>package</phase><goals><goal>single</goal></goals></execution></executions></plugin><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><configuration><source>6</source><target>6</target></configuration></plugin></plugins></build>

两个主要的类一个是代理类一个是方法的拦截器

agentParam这个参数可以传你想要监控的包名

package org.monitor;import net.bytebuddy.agent.builder.AgentBuilder;
import net.bytebuddy.description.method.MethodDescription;
import net.bytebuddy.description.type.TypeDescription;
import net.bytebuddy.dynamic.DynamicType;
import net.bytebuddy.implementation.MethodDelegation;
import net.bytebuddy.matcher.ElementMatchers;
import net.bytebuddy.utility.JavaModule;import java.lang.instrument.Instrumentation;public class MonitorAgent {public static void premain(String agentParam, Instrumentation inst) {System.out.println("premain开始--------->" + agentParam);// method指定哪些方法需要被拦截，ElementMathers.any指定了所有的方法，声明intercept拦截器AgentBuilder.Transformer transformer = new AgentBuilder.Transformer() {@Overridepublic DynamicType.Builder<?> transform(DynamicType.Builder<?> builder,TypeDescription typeDescription,ClassLoader classLoader,JavaModule javaModule) {return builder.method(ElementMatchers.<MethodDescription>any()).intercept(MethodDelegation.to(MonitorIntercept.class));}};/*** 1.type指定了agent拦截的包名，以[com.monitor]作为前缀* 2.指定了转换器transformer* 3.将配置安装到Instrumentation*/new AgentBuilder.Default().type(ElementMatchers.<TypeDescription>nameStartsWith(agentParam)).transform(transformer).installOn(inst);}
}

package org.monitor;import net.bytebuddy.implementation.bind.annotation.Origin;
import net.bytebuddy.implementation.bind.annotation.RuntimeType;
import net.bytebuddy.implementation.bind.annotation.SuperCall;import java.lang.reflect.Method;
import java.util.concurrent.Callable;public class MonitorIntercept {@RuntimeTypepublic static Object intercept(@Origin Method method,@SuperCall Callable<?> callable) throws Exception {long start = System.currentTimeMillis();try {return callable.call();} finally {System.out.println(method + ":" + (System.currentTimeMillis() - start) + "ms");}}
}

install 项目得到monitor-1.0-SNAPSHOT.jar

另一个用于被监控的项目monitorDemo，直接写一个main方法的项目就可以

new AgentBuilder.Default().type(ElementMatchers.<TypeDescription>nameStartsWith(agentParam)).transform(transformer).installOn(inst);

package org.monitor;/*** Hello world!**/
public class App 
{public static void main( String[] args ){System.out.println( "Hello World!" );try {Thread.sleep(10000);} catch (InterruptedException e) {throw new RuntimeException(e);}}
}

在运行monitorDemo的main的时候需要前面设置参数：

E:/monitor/target/monitor-1.0-SNAPSHOT.jar 就是Monitor项目install后的jar路径，=号后面是你想要监控的monitorDemo项目的包名路径

-javaagent:E:/monitor/target/monitor-1.0-SNAPSHOT.jar=org.monitor

运行后会打印出：

premain监控开始--------->包路径：org.monitor
Hello World!
public static void org.monitor.App.main(java.lang.String[]):10001msProcess finished with exit code 0

完成