Get value of a parameter of an annotation in Java

java reflection aspectj
Darek picture Darek · Nov 25, 2013 · Viewed 51.6k times · Source

So I've got a code:

@Path("/foo")
public class Hello {

@GET
@Produces("text/html")
public String getHtml(@Context Request request, @Context HttpServletRequest requestss){
  ...
}

I am using AspectJ to catch all calls to getHtml method. I would like to get parameters passed to @Produces and to @Path in my advice, i.e. "/foo" and "text/html" in this case. How can I do it using reflection ?

Answer

harsh picture harsh · Nov 25, 2013

To get value of the @Path parameter:

String path = Hello.class.getAnnotation(Path.class).value();

Similarly, Once you have hold of Method getHtml

Method m = Hello.class.getMethod("getHtml", ..);
String mime = m.getAnnotation(Produces.class).value;

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