Re: Method.equals() question

[Archie Cobbs]

Archie Cobbs wrote:
> The practical upshot of this is that the equals() methods that currently
> exist in Classpath for Field and Constructor need to be fixed. But the
> fixes could use "obj1.getDeclaringClass() == obj2.getDeclaringClass()"
> as part of the test.
> 
> Method also needs to be fixed, but for a different reason (it doesn't
> compare the return types as it should (referring to Classpath 0.05)).

Below are my patches (against 0.05) for fixing these equals() methods.

Cheers,
-Archie

__________________________________________________________________________
Archie Cobbs     *     Precision I/O      *     http://www.precisionio.com

diff -ur 
/home/archie/classpath/classpath-0.05/vm/reference/java/lang/reflect/Constructor.java
 ./Constructor.java
--- 
/home/archie/classpath/classpath-0.05/vm/reference/java/lang/reflect/Constructor.java
       Fri Oct 25 16:02:26 2002
+++ ./Constructor.java  Mon Mar  3 12:51:12 2003
@@ -38,6 +38,8 @@
 
 package java.lang.reflect;
 
+import java.util.Arrays;
+
 /**
  * The Constructor class represents a constructor of a class. It also allows
  * dynamic creation of an object, via reflection. Invocation on Constructor
@@ -160,7 +141,14 @@
    */
   public boolean equals(Object o)
   {
-    return this == o;
+    if (!(o instanceof Constructor))
+      return false;
+    Constructor that = (Constructor)o; 
+    if (this.getDeclaringClass() != that.getDeclaringClass())
+      return false;
+    if (!Arrays.equals(this.getParameterTypes(), that.getParameterTypes()))
+      return false;
+    return true;
   }
 
   /**
diff -ur 
/home/archie/classpath/classpath-0.05/vm/reference/java/lang/reflect/Field.java 
./Field.java
--- 
/home/archie/classpath/classpath-0.05/vm/reference/java/lang/reflect/Field.java 
    Fri Oct 25 16:02:26 2002
+++ ./Field.java        Mon Mar  3 12:47:44 2003
@@ -135,7 +125,16 @@
    */
   public boolean equals(Object o)
   {
-    return this == o;
+    if (!(o instanceof Field))
+      return false;
+    Field that = (Field)o; 
+    if (this.getDeclaringClass() != that.getDeclaringClass())
+      return false;
+    if (!this.getName().equals(that.getName()))
+      return false;
+    if (this.getType() != that.getType())
+      return false;
+    return true;
   }
 
   /**
diff -ur 
/home/archie/classpath/classpath-0.05/vm/reference/java/lang/reflect/Method.java
 ./Method.java
--- 
/home/archie/classpath/classpath-0.05/vm/reference/java/lang/reflect/Method.java
    Wed Dec 18 02:28:29 2002
+++ ./Method.java       Mon Mar  3 12:52:48 2003
@@ -38,6 +38,8 @@
 
 package java.lang.reflect;
 
+import java.util.Arrays;
+
 /**
  * The Method class represents a member method of a class. It also allows
  * dynamic invocation, via reflection. This works for both static and
@@ -144,57 +136,25 @@
   /**
    * Compare two objects to see if they are semantically equivalent.
    * Two Methods are semantically equivalent if they have the same declaring
-   * class, name, and parameter list.  This ignores different exception
-   * clauses or return types.
+   * class, name, parameter list, and return type.
    *
    * @param o the object to compare to
    * @return <code>true</code> if they are equal; <code>false</code> if not
    */
   public boolean equals(Object 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 this == o;
-      //
-      if (o == null)
-        return false;
-
-      if (!(o instanceof Method))
-        return false;
-
-      Method m = (Method)o;
-      if(!name.equals(m.name))
-         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;
+    if (!(o instanceof Method))
+      return false;
+    Method that = (Method)o; 
+    if (this.getDeclaringClass() != that.getDeclaringClass())
+      return false;
+    if (!this.getName().equals(that.getName()))
+      return false;
+    if (this.getReturnType() != that.getReturnType())
+      return false;
+    if (!Arrays.equals(this.getParameterTypes(), that.getParameterTypes()))
+      return false;
+    return true;
   }
 
   /**