0 Replies Latest reply on Oct 16, 2012 10:42 AM by 968571

    Getting return type of method which specializes the interface's return type

      I did this test with the following version of JRockit:

      java version "1.6.0_33"
      Java(TM) SE Runtime Environment (build 1.6.0_33-b03)
      Oracle JRockit(R) (build R28.2.4-14-151097-1.6.0_33-20120618-1634-windows-x86_64, compiled mode)

      Given the classes below:

      --- Base.java ---
      public interface Base {
      public Object getSomething();

      -- Derived.java ---
      public class Derived implements Base {
      public Long getSomething() {
           return 1L;

      -- Main.java ---
      import java.beans.*;

      public class Main {
      public static void main(String s[]) throws Exception {
           BeanInfo info = Introspector.getBeanInfo(Derived.class);
           for (PropertyDescriptor pd: info.getPropertyDescriptors()){
           System.out.printf("%s - %s\n", pd.getReadMethod().getName(), pd.getReadMethod().getReturnType());

      when executing Main, I see the following output:

      getClass - class java.lang.Class
      getSomething - class java.lang.Object

      I would expect the second line to be "getSomething - class java.lang.Long". Should I consider this a bug?