Get class annotations from Java source file

Question

I am parsing Java source files to collect various information about my classes. Therefore, I use JavaParser , since I could not find a good alternative (good suggestions can become "answers") to analyze the source files.

I have already managed to get annotations of all methods from my class. The code is as follows:

package de.mackaz; import japa.parser.JavaParser; import japa.parser.ParseException; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import japa.parser.ast.CompilationUnit; import japa.parser.ast.body.MethodDeclaration; import japa.parser.ast.expr.AnnotationExpr; import japa.parser.ast.expr.MarkerAnnotationExpr; import japa.parser.ast.expr.MemberValuePair; import japa.parser.ast.expr.NormalAnnotationExpr; import japa.parser.ast.visitor.VoidVisitorAdapter; import java.io.FileInputStream; public class JavaSourceUtils { public static void main(String[] args) throws Exception { File f = new File("/home/mackaz/SourceFile.java"); inspectJavaFile(f); } public static void inspectJavaFile(File pFile) throws FileNotFoundException, ParseException, IOException { CompilationUnit cu; FileInputStream in = new FileInputStream(pFile); try { cu = JavaParser.parse(in); } finally { in.close(); } new MethodVisitor().visit(cu, null); } /** * Simple visitor implementation for visiting MethodDeclaration nodes. */ private static class MethodVisitor extends VoidVisitorAdapter { @Override public void visit(MethodDeclaration n, Object arg) { System.out.println(n.getName()); if (n.getAnnotations() != null) { for (AnnotationExpr annotation : n.getAnnotations()) { System.out.println(annotation.getClass()); // MarkerAnnotations, for example @Test if (annotation.getClass().equals(MarkerAnnotationExpr.class)) { System.out.println("MarkerAnnotation:" + ((MarkerAnnotationExpr)annotation).getName()); } if (annotation.getClass().equals(NormalAnnotationExpr.class)) { for (MemberValuePair pair : ((NormalAnnotationExpr)annotation).getPairs()) { if (pair.getName().equals("groups")) System.out.println("Group:\"" + pair.getValue() + "\""); } } } } } } } 

Now, how can I get annotations of the class itself?

Answer 1

You are overriding the public void visit(MethodDeclaration n, Object arg) that the methods are visiting. You can also override public void visit(ClassOrInterfaceDeclaration n, A arg) or public void visit(ClassOrInterfaceType n, A arg) , which should give you access to the information you are looking for.

Answer 2

Here's how I solved it at the end - I added another visitor to "ClassVisitor":

 private static class ClassVisitor extends VoidVisitorAdapter { @Override public void visit(ClassOrInterfaceDeclaration n, Object arg) { for (AnnotationExpr ann: n.getAnnotations()) { System.out.println(ann.toString()); } } } 

Answer 3

It looks like you need to extend ModifierVisitorAdapter and implement

public Node visit(ClassOrInterfaceDeclaration n, A arg) {

Take a look at the implementation here to see what you can do:

  public Node visit(ClassOrInterfaceDeclaration n, A arg) { if (n.getJavaDoc() != null) { n.setJavaDoc((JavadocComment) n.getJavaDoc().accept(this, arg)); } List<AnnotationExpr> annotations = n.getAnnotations(); if (annotations != null) { for (int i = 0; i < annotations.size(); i++) { annotations.set(i, (AnnotationExpr) annotations.get(i).accept(this, arg)); } removeNulls(annotations); } List<TypeParameter> typeParameters = n.getTypeParameters(); if (typeParameters != null) { for (int i = 0; i < typeParameters.size(); i++) { typeParameters.set(i, (TypeParameter) typeParameters.get(i).accept(this, arg)); } removeNulls(typeParameters); } List<ClassOrInterfaceType> extendz = n.getExtends(); if (extendz != null) { for (int i = 0; i < extendz.size(); i++) { extendz.set(i, (ClassOrInterfaceType) extendz.get(i).accept(this, arg)); } removeNulls(extendz); } List<ClassOrInterfaceType> implementz = n.getImplements(); if (implementz != null) { for (int i = 0; i < implementz.size(); i++) { implementz.set(i, (ClassOrInterfaceType) implementz.get(i).accept(this, arg)); } removeNulls(implementz); } List<BodyDeclaration> members = n.getMembers(); if (members != null) { for (int i = 0; i < members.size(); i++) { members.set(i, (BodyDeclaration) members.get(i).accept(this, arg)); } removeNulls(members); } return n; }