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| © Copyright 2014 Contributors. |
| All rights reserved. |
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| |
| <h1>AspectJ 1.8.2 Readme</h1> |
| |
| <p>The full list of resolved issues in 1.8.2 is available |
| <a href="https://bugs.eclipse.org/bugs/buglist.cgi?query_format=advanced;bug_status=RESOLVED;bug_status=VERIFIED;bug_status=CLOSED;product=AspectJ;target_milestone=1.8.2;">here</a></h2>.</p> |
| |
| <ul> |
| <li>1.8.2 available 14-Aug-2014 |
| </ul> |
| |
| <h2>Notable changes</h2> |
| |
| <p>Although only a few bugs have been fixed here, they are quite important ones:</p> |
| |
| <h3>Update to more recent Eclipse Compiler</h3> |
| |
| <p>AspectJ is now based on a more up to date Eclipse compiler level (git hash 2b07958) so includes all the latest fixes</p> |
| |
| <h3>Correct handling of RuntimeInvisibleTypeAnnotations (type annotations without runtime visibility)</h3> |
| |
| <p>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.</p> |
| |
| <h3>Annotation processing</h3> |
| |
| <p>A very long standing issue, the AspectJ compiler now supports annotation processors thanks to some work by Sergey Stupin.</p> |
| |
| <p>Here is a short example, a very basic annotation and application:</p> |
| |
| <h4>Marker.java</h4> |
| <code><pre> |
| import java.lang.annotation.Retention; |
| import java.lang.annotation.RetentionPolicy; |
| |
| @Retention(RetentionPolicy.RUNTIME) |
| public @interface Marker { } |
| </pre></code> |
| |
| <h4>Code.java</h4> |
| <code><pre> |
| 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() {} |
| } |
| </pre></code> |
| |
| <p>And now a basic annotation processor. This processor will find methods in the source marked with the annotation <tt>Marker</tt> and for |
| each one generate an aspect tailored to advising that method (this *is* a contrived demo!)</p> |
| |
| <h4>DemoProcessor.java</h4> |
| <code><pre> |
| 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; |
| } |
| } |
| </pre></code> |
| |
| <p>With those sources, we compile the processor:</p> |
| <code><pre>ajc -1.6 DemoProcessor.java Marker.java</pre></code> |
| |
| <p>Now compile the code with the processor specified:</p> |
| <code><pre>ajc -1.6 -processor DemoProcessor -showWeaveInfo Code.java Marker.java</pre></code> |
| <code><pre> |
| 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) |
| </pre></code> |
| |
| <p>Notice the processor generates the aspects and then they are woven into the code being compiled immediately.</p> |
| |
| <p>Finally we can run it:</p> |
| <code><pre>java Code |
| boo running |
| too running |
| </pre></code> |
| |
| <p><b>Note:</b> There is still work to be done to get annotation processors behaving under AJDT. |
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