Re: Method.equals()

[Mark Wielaard]

Hi,

On Wed, 2002-02-20 at 03:19, Bryce McKinlay wrote:
> Cierniak, Michal wrote:
> >
> >But I thought that Bryce indicated in his message that he also liked the
> >patch submitted by Gansha.  It sounds like this modification is useful for
> >both ORP and GCJ since they both have their own internal data structures to
> >represent a method.
> 
> Right. Gansha's implementation should be the one that goes in 
> vm/reference. It may not be optimal for all VMs, but it is always 
> correct and most accurately matches the JDK spec, and it is the 
> implementation required for both ORP and GCJ.

OK. I think I understand the issue now. So this is the patch that
went in:

--- vm/reference/java/lang/reflect/Method.java  19 Feb 2002 22:52:10
-0000   
1.6
+++ vm/reference/java/lang/reflect/Method.java  2 Mar 2002 15:03:20 -0000
@@ -153,7 +153,46 @@
    */
   public boolean equals(Object o)
   {
-    return this == o;
+      // Implementation note:
+      // The following is a correct but possibly slow implementation.
+      //
+      // This class has a private field 'slot' that could be used by
+      // the VM implementation to "link" a particular method to a
Class.
+      // In that case equals could be simply implemented as:
+      //
+      // if (o instanceof Method)
+      // {
+      //    Method m = (Method)o;
+      //    return m.declaringClass == this.declaringClass
+      //           && m.slot == this.slot;
+      // }
+      // return false;
+      //
+      // If a VM uses the Method class as their native/internal
representation
+      // then just using the following would be optimal:
+      //
+      // return return this == o;
+      //
+
+      if (!(o instanceof Method))
+        return false;
+
+      Method m = (Method)o;
+      if(!name.equals(m.getName()))
+         return false;
+
+      if(declaringClass != m.declaringClass)
+         return false;
+
+      Class[] params1 = getParameterTypes();
+      Class[] params2 = m.getParameterTypes();
+      if(params1.length != params2.length)
+         return false;
+      for(int i = 0; i < params1.length; i++)
+         if(params1[i] != params2[i])
+             return false;
+
+      return true;
   }
 
   /**

There is now also a corresponding Mauve test case. Although I have been
unable to test it because for some reason my Orp doesn't like the CVS
Classpath anymore :(

Cheers,

Mark