Repeatable Annotations

It looks like the annotations can repeat according to Repeating Annotations.

I am still using

java version "1.8.0-ea"
Java(TM) SE Runtime Environment (build 1.8.0-ea-b113)
Java HotSpot(TM) 64-Bit Server VM (build 25.0-b55, mixed mode)

This code has a problem.

  1. Arrays.asList(typeMirror.getAnnotationsByType(RepeatableAnnotation.TypeUse.class))

    This does not print anything. There are two annotations.

This could be a problem with the particular JDK 8 build. The latest is b120. I have to try the latest build.

Update: This is most likely a code problem because even b120 does not help.

Update 1: This is not a code problem but b120 has some bugs according to the type-annotations-dev list.

The result is this.


Annotation [@com.test.RepeatableAnnotation.TypeUses({@com.test.RepeatableAnnotation.TypeUse(0), @com.test.RepeatableAnnotation.TypeUse(1)})] [com.test.RepeatableAnnotation.Test1]
[value()][{@com.test.RepeatableAnnotation.TypeUse(0), @com.test.RepeatableAnnotation.TypeUse(1)}]
Annotation [[]] [java.lang.Integer]

I am not able to get the annotations applied on the bound Integer

package com.test;

import java.lang.annotation.*;

public class RepeatableAnnotation {

    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.TYPE_USE)
    public @interface TypeUses {
        TypeUse[] value();
    }

    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.TYPE_USE)
    @Repeatable(value = TypeUses.class)
    protected @interface  TypeUse {
        int value();
    }

    @TypeUse(value = 0) @TypeUse(value = 1)class Test1< T extends @TypeUse(value = 2) @TypeUse(value = 3) Integer> {

        /**
         * A type annotation is permitted in front of a constructor declaration, where declaration annotations are already
         permitted.
         */
        @TypeUse(value = 0) <S> Test1(String s){

        }
    }

}

Annotation Processor


package com.test;

import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.*;
import javax.lang.model.type.ExecutableType;
import javax.lang.model.type.TypeMirror;
import javax.lang.model.type.TypeVisitor;
import javax.lang.model.util.SimpleTypeVisitor8;
import java.util.*;

import static javax.lang.model.util.ElementFilter.typesIn;

@SupportedAnnotationTypes("*")
@SupportedSourceVersion(SourceVersion.RELEASE_8)
public class RepeatableAnnotationFinder extends AbstractProcessor{


    public RepeatableAnnotationFinder(){
        super();
    }

    @Override
    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

        TypeElement tye = null;

        if( !roundEnv.processingOver()){

            Iterator<? extends Element> te = annotations.iterator();

            for (TypeElement element : typesIn(roundEnv.getRootElements()) ) {

                processEnclosedElements(element.getEnclosedElements(),
                                        roundEnv);

            }
        }
        return false;
    }

    private void processEnclosedElements(List<? extends Element> enclosedElements,
                                         RoundEnvironment roundEnv) {

        for( Element e : enclosedElements ){

            if (e.getKind() == ElementKind.CLASS){

                System.out.println( "Annotation [" + e.getAnnotationMirrors() + "] [" + e  + "]");

                processClassTypeParameters(e);
            }
        }
    }

    private void processClassTypeParameters(Element e) {

        for (TypeParameterElement typeParameterElement : ((TypeElement) e).getTypeParameters()) {

            for( AnnotationMirror am  : typeParameterElement.getAnnotationMirrors() ){

                System.out.println( "Annotation [" + am + "] [" + typeParameterElement  + "]");

                for(Map.Entry< ? extends ExecutableElement, ? extends AnnotationValue> m : am.getElementValues().entrySet()){

                    System.out.println( "[" + m.getKey() +"][" + m.getValue() + "]");

                }

            }

            for (TypeMirror typeMirror : typeParameterElement.getBounds()) {

                System.out.println( "Annotation [" + Arrays.asList(typeMirror.getAnnotationsByType(RepeatableAnnotation.TypeUse.class)) + "] [" + typeMirror  + "]");

            }
        }
    }
}

So I will wait for a newer build before trying this again.

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