Java AspectJ加载时编织-命令行项目

几天以来，我一直在为一个简单的项目苦苦挣扎，而这个项目我就是无法运行

我的目标是扩展.jar文件的功能，以便获得有关该jar内部工作的更多信息。jar不是开源的。 我使用了很多不同的概念将自己的代码“注入”到jvm中，比如“ASM”-库、BECL、Javassist，最后是AspectJ

AspectJ引起了我的注意，因为它似乎更易于使用，而且级别更高。为了在将AspectJ与封闭源代码.jar一起使用之前尝试它的工作方式，我设置了测试项目：

项目1:

为了测试它，我想创建一个简单的项目，其中包含一个应该编译并打包到.jar文件中的类。以后应该使用方面来监视此类。我从互联网上的一个示例中获取了这个类的源代码： 类的文件内容如下所示： YourClass.java：

package com.test.java.instrumentation;

public class YourClass {

    public static void main(String[] args) {
        YourClass yourClass = new YourClass();
        yourClass.yourMethodBefore();
        yourClass.yourMethodAfter();
        yourClass.yourMethodAround(1);
        yourClass.yourMethodAround(1,"Test");
    }

    public void yourMethodBefore() {
        System.out.println("Executing TestTarget.yourMethodBefore()");
    }

    public void yourMethodAfter(){
        System.out.println("Executing TestTarget.yourMethodAfter()");
    }

    public void yourMethodAround(Integer i){
        System.out.println("Executing TestTarget.yourMethodAround()");
        System.out.println("i : "+i);
    }

    public void yourMethodAround(Integer i,String x){
        System.out.println("Executing TestTarget.yourMethodAround()");
        System.out.println("i : "+i);
        System.out.println("x : "+x);
    }
}

我使用以下命令编译代码：

javac -d bin -cp ./src/ ./src/com/test/java/instrumentation/YourClass.java

javac -cp ./lib/aspectjrt.jar;.lib/aspejctjweaver.jar;./src;. -d ./bin/ ./src/com/test/java/instrumentation/YourAspect.java

java -Daj.weaving.verbose=true -Dorg.aspectj.weaver.showWeaveInfo=true -javaagent:./Aspect/lib/aspectjweaver.jar -cp ./Aspect/lib/aspectjrt.jar;./Aspect/lib/aspejctjtools.jar;. -jar ./JavaProgram/bin/program.jar

命令运行时没有错误。 在下一步中，我创建了一个清单文件，其中包含在.jar文件中运行该类所需的信息： MANIFEST.MF：

Manifest-Version: 1.0
Main-Class: com.test.java.instrumentation.YourClass
Built-By: Me
Build-Jdk: 1.8.0_131

在下一步中，我将创建一个.jar：

cd bin\
jar cvfm program.jar ..\meta-inf\manifest.mf .

.jar可以通过以下方式成功执行：

java -jar program.jar

输出如下所示：

Executing TestTarget.yourMethodBefore()
Executing TestTarget.yourMethodAfter()
Executing TestTarget.yourMethodAround()
i : 1
Executing TestTarget.yourMethodAround()
i : 1
x : Test

到目前为止还不错。步骤1已完成。这是一个示例应用程序，稍后应使用AspectJ的加载时编织扩展它的附加功能

项目2: 在下一步中，我想创建一个AspectJ.jar文件，其中包含扩展Project1功能的代码： Priject2（YourAspect.java）的内容如下：

package com.test.java.instrumentation;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.aspectj.lang.JoinPoint;

@Aspect
public class YourAspect {

    //Patterns
    //blank = modifier (public/private/protected or default(blank) should be looked for
    //* = return type to look for. Void/Object/Primitive type
    //com.jayway.YourClass.yourMethodBefore(..) = PackageName . ClassName . methodName (parameters)
    @Before("execution (* com.test.java.instrumentation.YourClass.yourMethodBefore(..))")
    //JointPoint = the reference of the call to the method
    public void beforeAdvice(JoinPoint joinPoint) {
        System.out.println("YourAspect's BeforeAdvice's body is now executed Before yourMethodBefore is called.");
    }
    //Patterns
    //public = look for the specific modifier named public
    //!Object = Basically we are looking for void or primitives. But if we specified Object we could get a good pattern
    //com.jayway.YourClass.yourMethodBefore(..) = PackageName . ClassName . methodName (parameters)
    @After("execution (public !Object com.test.java.instrumentation.YourClass.yourMethodAfter(..))")
    public void afterAdvice(JoinPoint joinPoint) {
        System.out.println("YourAspect's afterAdvice's body is now executed After yourMethodAfter is called.");
    }
    //Patterns
    //!private = look for any modifier that's not private
    //void = looking for method with void
    //com.jayway.YourClass.yourMethodBefore(..) = PackageName . ClassName . methodName (parameters)
    @Around("execution (!private void com.test.java.instrumentation.YourClass.yourMethodAround(Integer,..))")
    //ProceedingJointPoint = the reference of the call to the method.
    //The difference between ProceedingJointPoint and JointPoint is that a JointPoint can't be continued (proceeded)
    //A ProceedingJointPoint can be continued (proceeded) and is needed for an Around advice
    public Object aroundAdvice(ProceedingJoinPoint joinPoint) throws Throwable {
        //Default Object that we can use to return to the consumer
        Object returnObject = null;
        try {
            System.out.println("YourAspect's aroundAdvice's body is now executed Before yourMethodAround is called.");
            //We choose to continue the call to the method in question
            returnObject = joinPoint.proceed();
            //If no exception is thrown we should land here and we can modify the returnObject, if we want to.
        } catch (Throwable throwable) {
            //Here we can catch and modify any exceptions that are called
            //We could potentially not throw the exception to the caller and instead return "null" or a default object.
            throw throwable;
        }
        finally {
            //If we want to be sure that some of our code is executed even if we get an exception
            System.out.println("YourAspect's aroundAdvice's body is now executed After yourMethodAround is called.");
        }

        return returnObject;
    }
    //Patterns
    //blank = modifier (public/private/protected or default(blank) should be looked for
    //* = return type to look for. Void/Object/Primitive type
    //com.jayway.YourClass.yourMethod*(..) = PackageName . ClassName . * (parameters)
    //Where the "*" will catch any method name
    @After("execution ( * com.test.java.instrumentation.YourClass.*(..))")
    //JointPoint = the reference of the call to the method
    public void printNewLine(JoinPoint pointcut){
        //Just prints new lines after each method that's executed in
        System.out.print("\n\r");
    }
}

[AppClassLoader@18b4aac2] info AspectJ Weaver Version 1.8.10 built on Monday Dec 12, 2016 at 19:07:48 GMT
[AppClassLoader@18b4aac2] info register classloader sun.misc.Launcher$AppClassLoader@18b4aac2
[AppClassLoader@18b4aac2] info no configuration found. Disabling weaver for class loader sun.misc.Launcher$AppClassLoader@18b4aac2
Executing TestTarget.yourMethodBefore()
Executing TestTarget.yourMethodAfter()
Executing TestTarget.yourMethodAround()
i : 1
Executing TestTarget.yourMethodAround()
i : 1
x : Test

我还创建了MANIFEST.FM：

Manifest-Version: 1.0
Main-Class: com.test.java.instrumentation.YourAspect
Built-By: Me
Build-Jdk: 1.8.0_131

和一个aop.xml：

<aspectj>

    <aspects>
        <aspect name="com.test.java.instrumentation.YourAspect"/>
   </aspects>

   <weaver options="-XlazyTjp">
       <include within="com.test.java.instrumentation..*"/>
   </weaver>

</aspectj>

生成的类文件与清单和aop.xml一起打包到.jar中：

cd bin\
jar cvfm aspect.jar ..\meta-inf\manifest.mf ..\meta-inf\aop.xml .

当我尝试运行示例程序（Project1）并尝试编织方面（Project2）时，我使用以下命令：

javac -d bin -cp ./src/ ./src/com/test/java/instrumentation/YourClass.java

javac -cp ./lib/aspectjrt.jar;.lib/aspejctjweaver.jar;./src;. -d ./bin/ ./src/com/test/java/instrumentation/YourAspect.java

java -Daj.weaving.verbose=true -Dorg.aspectj.weaver.showWeaveInfo=true -javaagent:./Aspect/lib/aspectjweaver.jar -cp ./Aspect/lib/aspectjrt.jar;./Aspect/lib/aspejctjtools.jar;. -jar ./JavaProgram/bin/program.jar

加载失败，导致的错误如下：

package com.test.java.instrumentation;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.aspectj.lang.JoinPoint;

@Aspect
public class YourAspect {

    //Patterns
    //blank = modifier (public/private/protected or default(blank) should be looked for
    //* = return type to look for. Void/Object/Primitive type
    //com.jayway.YourClass.yourMethodBefore(..) = PackageName . ClassName . methodName (parameters)
    @Before("execution (* com.test.java.instrumentation.YourClass.yourMethodBefore(..))")
    //JointPoint = the reference of the call to the method
    public void beforeAdvice(JoinPoint joinPoint) {
        System.out.println("YourAspect's BeforeAdvice's body is now executed Before yourMethodBefore is called.");
    }
    //Patterns
    //public = look for the specific modifier named public
    //!Object = Basically we are looking for void or primitives. But if we specified Object we could get a good pattern
    //com.jayway.YourClass.yourMethodBefore(..) = PackageName . ClassName . methodName (parameters)
    @After("execution (public !Object com.test.java.instrumentation.YourClass.yourMethodAfter(..))")
    public void afterAdvice(JoinPoint joinPoint) {
        System.out.println("YourAspect's afterAdvice's body is now executed After yourMethodAfter is called.");
    }
    //Patterns
    //!private = look for any modifier that's not private
    //void = looking for method with void
    //com.jayway.YourClass.yourMethodBefore(..) = PackageName . ClassName . methodName (parameters)
    @Around("execution (!private void com.test.java.instrumentation.YourClass.yourMethodAround(Integer,..))")
    //ProceedingJointPoint = the reference of the call to the method.
    //The difference between ProceedingJointPoint and JointPoint is that a JointPoint can't be continued (proceeded)
    //A ProceedingJointPoint can be continued (proceeded) and is needed for an Around advice
    public Object aroundAdvice(ProceedingJoinPoint joinPoint) throws Throwable {
        //Default Object that we can use to return to the consumer
        Object returnObject = null;
        try {
            System.out.println("YourAspect's aroundAdvice's body is now executed Before yourMethodAround is called.");
            //We choose to continue the call to the method in question
            returnObject = joinPoint.proceed();
            //If no exception is thrown we should land here and we can modify the returnObject, if we want to.
        } catch (Throwable throwable) {
            //Here we can catch and modify any exceptions that are called
            //We could potentially not throw the exception to the caller and instead return "null" or a default object.
            throw throwable;
        }
        finally {
            //If we want to be sure that some of our code is executed even if we get an exception
            System.out.println("YourAspect's aroundAdvice's body is now executed After yourMethodAround is called.");
        }

        return returnObject;
    }
    //Patterns
    //blank = modifier (public/private/protected or default(blank) should be looked for
    //* = return type to look for. Void/Object/Primitive type
    //com.jayway.YourClass.yourMethod*(..) = PackageName . ClassName . * (parameters)
    //Where the "*" will catch any method name
    @After("execution ( * com.test.java.instrumentation.YourClass.*(..))")
    //JointPoint = the reference of the call to the method
    public void printNewLine(JoinPoint pointcut){
        //Just prints new lines after each method that's executed in
        System.out.print("\n\r");
    }
}

[AppClassLoader@18b4aac2] info AspectJ Weaver Version 1.8.10 built on Monday Dec 12, 2016 at 19:07:48 GMT
[AppClassLoader@18b4aac2] info register classloader sun.misc.Launcher$AppClassLoader@18b4aac2
[AppClassLoader@18b4aac2] info no configuration found. Disabling weaver for class loader sun.misc.Launcher$AppClassLoader@18b4aac2
Executing TestTarget.yourMethodBefore()
Executing TestTarget.yourMethodAfter()
Executing TestTarget.yourMethodAround()
i : 1
Executing TestTarget.yourMethodAround()
i : 1
x : Test

如何将我的方面（Project2）注入到正在运行的program.jar（Project1）中？ 你有什么想法吗

我在下面的链接中附加了所有文件，包括我创建的源代码和清单（两个项目）作为.zip文件，因此您也可以尝试我迄今为止所做的工作。这可能会帮助您更容易发现我的错误。该项目设计为在windows命令行上运行

链接：

---

非常感谢你的想法

首先，上传压缩的可执行文件很简单。下次托管源。无论如何，您的编译命令看起来有点不对劲-难道.jar不应该遵循-cp选项吗？看起来这使得编译无法如期完成。您能提供您正在尝试使用的.jar的名称吗？还是源头？查看生成的.jar内容-它只包含示例类.zip文件包含源代码、编译命令和目录结构（包括.jar文件）。如果你不信任他们，就不要管理这些罐子。两种编译都工作正常，不会抛出错误。正如我所说，源代码包含在.zip文件中。有人找到了解决方案吗？我也被困在同一个地方problem@HurrDurr你找到解决办法了吗？