[JBoss-dev] [AOP on JBoss (Aspects/JBoss)] - added Aspects

[Bill B. <nu...@jb...>]

View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=3820391#3820391

Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&p=3820391

I just added a new feature in HEAD (cvs checkout jboss-head)



Added the ability to define Aspects.  Aspects are a Java class that contains multiple advices.  An advice in an Aspect class maps to a particular method.



Here's what the XML and code looks like.  POJOAspectTester is what we're interception.  Aspect is the class that contains advices.  The XML defines the aspect and then binds the advice of the aspect within a pointcut.



You can define a scope for the aspect.  This is PER_VM, PER_CLASS, or PER_INSTANCE.  (FYI, i'll be adding this for interceptors soon too).



Note on performance.  Aspects are much slower than regular interceptors because reflection is required to execute the advices where regular interceptors this is not required.





   [aspect class="org.jboss.test.aop.bean.Aspect" scope="PER_VM"/]



   [constructor-pointcut constructor="org.jboss.test.aop.bean.POJOAspectTester()"]

      [bind]

         [advice name="interceptConstructor" aspect="org.jboss.test.aop.bean.Aspect"/]

      [/bind]

   [/constructor-pointcut]



   [method-pointcut class="org.jboss.test.aop.bean.POJOAspectTester" methodExpr="void someMethod()"]

      [bind]

         [advice name="interceptMethod" aspect="org.jboss.test.aop.bean.Aspect"/]

      [/bind]

   [/method-pointcut]







public class POJOAspectTester

{

   public String marker = "error";

   public int field;



   public POJOAspectTester() {}



   public void someMethod() {}

}



public class Aspect

{

   public Object interceptConstructor(ConstructorInvocation invocation) throws Throwable

   {

      Object rtn = invocation.invokeNext();

      POJOAspectTester pojo = (POJOAspectTester)rtn;

      pojo.marker = "interceptConstructor";

      return rtn;

   }



   public Object interceptField(FieldInvocation invocation) throws Throwable

   {

      Object rtn = invocation.invokeNext();

      POJOAspectTester pojo = (POJOAspectTester)invocation.targetObject;

      pojo.marker = "interceptField";

      return rtn;

   }



   public Object interceptMethod(MethodInvocation invocation) throws Throwable

   {

      Object rtn = invocation.invokeNext();

      POJOAspectTester pojo = (POJOAspectTester)invocation.targetObject;

      pojo.marker = "interceptMethod";

      return rtn;

   }

}