code: public static void assertSame(String message, Object expected, Object actual) {
          if (expected == actual) {
              return;
          }
          failNotSame(message, expected, actual);
      }
docs: Asserts that two objects refer to the same object. If they are not, an
  {@link AssertionError} is thrown with the given message.
  
  @param message the identifying message for the {@link AssertionError} (<code>null</code>
  okay)
  @param expected the expected object
  @param actual the object to compare to <code>expected</code>