© Copyright 2014 Contributors. All rights reserved.

# AspectJ 1.8.2 Readme

The full list of resolved issues in 1.8.2 is available here.

- 1.8.2 available 14-Aug-2014

## Notable changes

Although only a few bugs have been fixed here, they are quite important ones:

### Update to more recent Eclipse Compiler

AspectJ is now based on a more up to date Eclipse compiler level (git hash 2b07958) so includes all the latest fixes

### Correct handling of RuntimeInvisibleTypeAnnotations (type annotations without runtime visibility)

For anyone weaving code containing these kind of type annotations, this is an important fix. Although AspectJ does not currently support pointcuts matching on these kinds of annotation it was crashing when they were encountered. That is now fixed.

### Annotation processing

A very long standing issue, the AspectJ compiler now supports annotation processors thanks to some work by Sergey Stupin.

Here is a short example, a very basic annotation and application:

#### Marker.java

`

    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;

    @Retention(RetentionPolicy.RUNTIME)
    public @interface Marker { }

`

#### Code.java

`

    public class Code {

      public static void main(String []argv) {
        new Code().moo();
        new Code().boo();
        new Code().too();
        new Code().woo();
      }

      public void moo() {}

      @Marker
      public void boo() {}

      @Marker
      public void too() {}

      public void woo() {}
    }

`

And now a basic annotation processor. This processor will find methods in the source marked with the annotation `Marker` and for each one generate an aspect tailored to advising that method (this *is* a contrived demo!)

#### DemoProcessor.java

`

    import java.io.*;
    import javax.tools.*;
    import java.util.*;
    import javax.annotation.processing.*;
    import javax.lang.model.*;
    import javax.lang.model.element.*;

    @SupportedAnnotationTypes(value= {"*"})
    @SupportedSourceVersion(SourceVersion.RELEASE_6)
    public class DemoProcessor extends AbstractProcessor {

      private Filer filer;

      @Override
      public void init(ProcessingEnvironment env) {
        filer = env.getFiler();
      }

      @Override
      public boolean process(Set elements, RoundEnvironment env) {
        // Discover anything marked with @Marker
        for (Element element: env.getElementsAnnotatedWith(Marker.class)) {
          if (element.getKind() == ElementKind.METHOD) {
            // For any methods we find, create an aspect:
            String methodName = element.getSimpleName().toString();
            String aspectText =
                "public aspect Advise_"+methodName+" {\n"+
                "  before(): execution(* "+methodName+"(..)) {\n"+
                "    System.out.println(\""+methodName+" running\");\n"+
                "  }\n"+
                "}\n";
            try {
              JavaFileObject file = filer.createSourceFile("Advise_"+methodName, element);
              file.openWriter().append(aspectText).close();
              System.out.println("Generated aspect to advise "+element.getSimpleName());
            } catch (IOException ioe) {
              // already creates message can appear if processor runs more than once
              if (!ioe.getMessage().contains("already created")) {
                ioe.printStackTrace();
              }
            }
          }
        }
        return true;
      }
    }

`

With those sources, we compile the processor:

`

    ajc -1.6 DemoProcessor.java Marker.java

`

Now compile the code with the processor specified:

`

    ajc -1.6 -processor DemoProcessor -showWeaveInfo Code.java Marker.java

` `

    Generated aspect to advise too
    Generated aspect to advise boo
    Join point 'method-execution(void Code.boo())' in Type 'Code' (Code.java:14) advised by before advice from 'Advise_boo' (Advise_boo.java:2)
    Join point 'method-execution(void Code.too())' in Type 'Code' (Code.java:17) advised by before advice from 'Advise_too' (Advise_too.java:2)

`

Notice the processor generates the aspects and then they are woven into the code being compiled immediately.

Finally we can run it:

`

    java Code
    boo running
    too running

`

Note: There is still work to be done to get annotation processors behaving under AJDT.