在 springboot 中使用 aop 的 bytebuddy 不起作用
bytebuddy with aop in springboot not work
我尝试使用bytebuddy在springboot中实现aop。代码如下:
package klordy.learning.annotation;
@Target(METHOD)
@Retention(RUNTIME)
@Documented
public @interface CostTime {
}
package klordy.learning.agent;
public class Agent {
private static Agent instance = new Agent();
private Logger logger = LoggerFactory.getLogger(Agent.class);
private Agent() {}
public static Agent getInstance(){ return instance; }
public void install() {
ByteBuddyAgent.install();
AgentBuilder.Listener listener = new AgentBuilder.Listener() {
// do nothing
...
};
new AgentBuilder.Default()
.type(ElementMatchers.nameStartsWith("klordy.learning"))
.transform((builder, typeDescription, classLoader, module) ->
builder.visit(Advice.to(TimeAdvice.class).on(ElementMatchers.isAnnotatedWith(named("klordy.learning.annotation.CostTime")))))
.with(listener)
// *** added as supposed, but still seems not work.
.with(AgentBuilder.RedefinitionStrategy.RETRANSFORMATION)
.installOnByteBuddyAgent();
logger.info("byte buddy modification done.");
}
}
public class TimeAdvice {
@Advice.OnMethodEnter
static long enter(@Advice.AllArguments Object args[], @Advice.Origin Method method){
return System.currentTimeMillis();
}
@Advice.OnMethodExit
static void exit(@Advice.Enter long startTime,
@Advice.Return(typing = Assigner.Typing.DYNAMIC) Object result,
@Advice.Origin Method method,
@Advice.Thrown Throwable throwable){
if(throwable != null){
System.out.println("error func " + System.currentTimeMillis());
}else {
System.out.println("func takes " + (System.currentTimeMillis() - startTime));
}
}
}
springboot的监听如下:
public class AppEnvListener implements ApplicationListener<ApplicationEnvironmentPreparedEvent> {
private Logger logger = LoggerFactory.getLogger(AppEnvListener.class);
@Override
public void onApplicationEvent(ApplicationEnvironmentPreparedEvent applicationEnvironmentPreparedEvent) {
Agent.getInstance().install();
logger.info("finished byte buddy installation.");
}
}
最后在springboot启动时注册监听:
@SpringBootApplication
@ComponentScan(basePackages = "klordy.learning")
public class SpringBootDemoApplication {
public static void main(String[] args) {
SpringApplication application = new SpringApplication(SpringBootDemoApplication.class);
// register listener
application.addListeners(new AppEnvListener());
application.run(args);
}
}
当我启动应用程序时,调试记录器显示正常。但是,处理请求时 aop 不起作用。我究竟做错了什么?我很困惑...
您的 class 可能已经加载。
在您的代理配置中设置 .with(RetransformationStrategy.RETRANSFORM)
或在您的 main
方法中加载 Spring 之前安装您的代理。
好的,我想我通过使用 Spring Boot 重现您的情况发现了您的问题。不过,如果没有 Spring 也会发生这种情况。基本上你打 this problem.
因此,如果您将建议修改为 @Advice.OnMethodExit(onThrowable = Throwable.class)
,应该没问题。您还应该将 .disableClassFormatChanges()
添加到您的代理中,顺便说一句。它有助于避免重新转换以前加载的问题 类。 JVM 要求它们在结构上不能改变。
我是怎么知道发生了什么事的?我在 ByteBuddy 中激活了控制台登录。以前我用过你的监听器,让它记录每一个动作,所以我可以看到 BB 实际上被触发了。但是 BB 日志记录确实显示了异常,因为您错误地使用了 @Advice.Thrown
(在建议注释中没有 onThrowable = Throwable.class
)。
public void install() {
ByteBuddyAgent.install();
new AgentBuilder.Default()
.disableClassFormatChanges()
.with(RETRANSFORMATION)
.with(AgentBuilder.RedefinitionStrategy.Listener.StreamWriting.toSystemError())
.with(AgentBuilder.Listener.StreamWriting.toSystemError().withTransformationsOnly())
.with(AgentBuilder.InstallationListener.StreamWriting.toSystemError())
.type(ElementMatchers.nameStartsWith("klordy.learning"))
.transform((builder, typeDescription, classLoader, module) ->
builder.visit(
Advice
.to(TimeAdvice.class)
.on(isAnnotatedWith(named("klordy.learning.annotation.CostTime")))
)
)
.installOnByteBuddyAgent();
logger.info("byte buddy modification done.");
}
我尝试使用bytebuddy在springboot中实现aop。代码如下:
package klordy.learning.annotation;
@Target(METHOD)
@Retention(RUNTIME)
@Documented
public @interface CostTime {
}
package klordy.learning.agent;
public class Agent {
private static Agent instance = new Agent();
private Logger logger = LoggerFactory.getLogger(Agent.class);
private Agent() {}
public static Agent getInstance(){ return instance; }
public void install() {
ByteBuddyAgent.install();
AgentBuilder.Listener listener = new AgentBuilder.Listener() {
// do nothing
...
};
new AgentBuilder.Default()
.type(ElementMatchers.nameStartsWith("klordy.learning"))
.transform((builder, typeDescription, classLoader, module) ->
builder.visit(Advice.to(TimeAdvice.class).on(ElementMatchers.isAnnotatedWith(named("klordy.learning.annotation.CostTime")))))
.with(listener)
// *** added as supposed, but still seems not work.
.with(AgentBuilder.RedefinitionStrategy.RETRANSFORMATION)
.installOnByteBuddyAgent();
logger.info("byte buddy modification done.");
}
}
public class TimeAdvice {
@Advice.OnMethodEnter
static long enter(@Advice.AllArguments Object args[], @Advice.Origin Method method){
return System.currentTimeMillis();
}
@Advice.OnMethodExit
static void exit(@Advice.Enter long startTime,
@Advice.Return(typing = Assigner.Typing.DYNAMIC) Object result,
@Advice.Origin Method method,
@Advice.Thrown Throwable throwable){
if(throwable != null){
System.out.println("error func " + System.currentTimeMillis());
}else {
System.out.println("func takes " + (System.currentTimeMillis() - startTime));
}
}
}
springboot的监听如下:
public class AppEnvListener implements ApplicationListener<ApplicationEnvironmentPreparedEvent> {
private Logger logger = LoggerFactory.getLogger(AppEnvListener.class);
@Override
public void onApplicationEvent(ApplicationEnvironmentPreparedEvent applicationEnvironmentPreparedEvent) {
Agent.getInstance().install();
logger.info("finished byte buddy installation.");
}
}
最后在springboot启动时注册监听:
@SpringBootApplication
@ComponentScan(basePackages = "klordy.learning")
public class SpringBootDemoApplication {
public static void main(String[] args) {
SpringApplication application = new SpringApplication(SpringBootDemoApplication.class);
// register listener
application.addListeners(new AppEnvListener());
application.run(args);
}
}
当我启动应用程序时,调试记录器显示正常。但是,处理请求时 aop 不起作用。我究竟做错了什么?我很困惑...
您的 class 可能已经加载。
在您的代理配置中设置 .with(RetransformationStrategy.RETRANSFORM)
或在您的 main
方法中加载 Spring 之前安装您的代理。
好的,我想我通过使用 Spring Boot 重现您的情况发现了您的问题。不过,如果没有 Spring 也会发生这种情况。基本上你打 this problem.
因此,如果您将建议修改为 @Advice.OnMethodExit(onThrowable = Throwable.class)
,应该没问题。您还应该将 .disableClassFormatChanges()
添加到您的代理中,顺便说一句。它有助于避免重新转换以前加载的问题 类。 JVM 要求它们在结构上不能改变。
我是怎么知道发生了什么事的?我在 ByteBuddy 中激活了控制台登录。以前我用过你的监听器,让它记录每一个动作,所以我可以看到 BB 实际上被触发了。但是 BB 日志记录确实显示了异常,因为您错误地使用了 @Advice.Thrown
(在建议注释中没有 onThrowable = Throwable.class
)。
public void install() {
ByteBuddyAgent.install();
new AgentBuilder.Default()
.disableClassFormatChanges()
.with(RETRANSFORMATION)
.with(AgentBuilder.RedefinitionStrategy.Listener.StreamWriting.toSystemError())
.with(AgentBuilder.Listener.StreamWriting.toSystemError().withTransformationsOnly())
.with(AgentBuilder.InstallationListener.StreamWriting.toSystemError())
.type(ElementMatchers.nameStartsWith("klordy.learning"))
.transform((builder, typeDescription, classLoader, module) ->
builder.visit(
Advice
.to(TimeAdvice.class)
.on(isAnnotatedWith(named("klordy.learning.annotation.CostTime")))
)
)
.installOnByteBuddyAgent();
logger.info("byte buddy modification done.");
}