refactor compile time transformation

src/java/grails/plugin/cache/CacheEvict.java

@@ -19,7 +19,7 @@
 @Retention(RetentionPolicy.RUNTIME)
 @Inherited
 @Documented
-@GroovyASTTransformationClass("grails.plugin.cache.compiler.CacheEvictTransformation")
+@GroovyASTTransformationClass("grails.plugin.cache.compiler.CacheTransformation")
 public @interface CacheEvict {
 
 	/**

src/java/grails/plugin/cache/CachePut.java

@@ -21,7 +21,7 @@
 @Retention(RetentionPolicy.RUNTIME)
 @Inherited
 @Documented
-@GroovyASTTransformationClass("grails.plugin.cache.compiler.CachePutTransformation")
+@GroovyASTTransformationClass("grails.plugin.cache.compiler.CacheTransformation")
 public @interface CachePut {
 
 	/**

src/java/grails/plugin/cache/Cacheable.java

@@ -20,7 +20,7 @@
 @Retention(RetentionPolicy.RUNTIME)
 @Inherited
 @Documented
-@GroovyASTTransformationClass("grails.plugin.cache.compiler.CacheableTransformation")
+@GroovyASTTransformationClass("grails.plugin.cache.compiler.CacheTransformation")
 public @interface Cacheable {
 
     /**

src/java/grails/plugin/cache/compiler/CacheTransformation.java

@@ -0,0 +1,50 @@
+package grails.plugin.cache.compiler;
+
+import java.lang.annotation.Annotation;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.codehaus.groovy.ast.ASTNode;
+import org.codehaus.groovy.ast.AnnotatedNode;
+import org.codehaus.groovy.ast.AnnotationNode;
+import org.codehaus.groovy.ast.ClassNode;
+import org.codehaus.groovy.ast.expr.Expression;
+import org.codehaus.groovy.control.CompilePhase;
+import org.codehaus.groovy.control.SourceUnit;
+import org.codehaus.groovy.transform.ASTTransformation;
+import org.codehaus.groovy.transform.GroovyASTTransformation;
+
+@GroovyASTTransformation(phase = CompilePhase.CANONICALIZATION)
+public class CacheTransformation implements ASTTransformation {
+
+	@SuppressWarnings("serial")
+	private static final Map<ClassNode, Class<? extends Annotation>> GRAILS_ANNOTATION_CLASS_NODE_TO_SPRING_ANNOTATION = new HashMap<ClassNode, Class<? extends Annotation>>(){{
+		put(new ClassNode(grails.plugin.cache.Cacheable.class), org.springframework.cache.annotation.Cacheable.class);
+		put(new ClassNode(grails.plugin.cache.CachePut.class), org.springframework.cache.annotation.CachePut.class);
+		put(new ClassNode(grails.plugin.cache.CacheEvict.class), org.springframework.cache.annotation.CacheEvict.class);
+	}};
+
+    public void visit(final ASTNode[] astNodes, final SourceUnit sourceUnit) {
+        final ASTNode firstNode = astNodes[0];
+        final ASTNode secondNode = astNodes[1];
+        if (!(firstNode instanceof AnnotationNode) || !(secondNode instanceof AnnotatedNode)) {
+            throw new RuntimeException("Internal error: wrong types: " + firstNode.getClass().getName() + " / " + secondNode.getClass().getName());
+        }
+
+        final AnnotationNode grailsCacheAnnotationNode = (AnnotationNode) firstNode;
+        final AnnotatedNode parent = (AnnotatedNode) secondNode;
+        final AnnotationNode springCacheableAnnotationNode = getCorrespondingSpringAnnotation(grailsCacheAnnotationNode);
+        parent.addAnnotation(springCacheableAnnotationNode);
+    }
+
+	protected AnnotationNode getCorrespondingSpringAnnotation(final AnnotationNode grailsCacheAnnotationNode) {
+		final Map<String, Expression> grailsAnnotationMembers = grailsCacheAnnotationNode.getMembers();
+
+		final Class<? extends Annotation> springAnnotationClass = GRAILS_ANNOTATION_CLASS_NODE_TO_SPRING_ANNOTATION.get(grailsCacheAnnotationNode.getClassNode());
+		final AnnotationNode springCacheableAnnotationNode = new AnnotationNode(new ClassNode(springAnnotationClass));
+        for(Map.Entry<String, Expression> entry : grailsAnnotationMembers.entrySet()) {
+            springCacheableAnnotationNode.addMember(entry.getKey(), entry.getValue());
+        }
+		return springCacheableAnnotationNode;
+	}
+}