Changeset 12660

Timestamp:

05/08/10 21:55:47 (13 years ago)

Author:

astalla

Message:

Fixed and rationalized class precedence list computation for java-class metaclasses.

File:

• trunk/abcl/src/org/armedbear/lisp/java.lisp (modified) (3 diffs)

trunk/abcl/src/org/armedbear/lisp/java.lisp

@@ -326 +326 @@
 
 ;;; JAVA-CLASS support
+(defconstant +java-lang-object+ (jclass "java.lang.Object"))
 
 (defclass java-class (standard-class)
@@ -331 +332 @@
      :initform (error "class is required")
      :reader java-class-jclass)))
+
+;;init java.lang.Object class
+(defconstant +java-lang-object-class+
+  (%register-java-class +java-lang-object+
+      (mop::ensure-class (make-symbol "java.lang.Object")
+             :metaclass (find-class 'java-class)
+             :direct-superclasses (list (find-class 'java-object))
+             :java-class +java-lang-object+)))
 
 (defun ensure-java-class (jclass)
@@ -337 +346 @@
   class
   (%register-java-class
-   jclass (mop::ensure-class (make-symbol (jclass-name jclass))
-           :metaclass (find-class 'java-class)
-           :direct-superclasses (if (jclass-superclass-p jclass (jclass "java.lang.Object"))
-                  (list (find-class 'java-object))
-                  (mapcar #'ensure-java-class
-                    (delete nil
-                      (concatenate 'list (list (jclass-superclass jclass))
-                       (jclass-interfaces jclass)))))
-           :java-class jclass)))))
+   jclass (mop::ensure-class
+     (make-symbol (jclass-name jclass))
+     :metaclass (find-class 'java-class)
+     :direct-superclasses (mapcar #'ensure-java-class
+                (remove-duplicates
+                 (delete nil
+                   (concatenate 'list
+                    (list (jclass-superclass jclass))
+                    (jclass-interfaces jclass)))
+                 :key #'jclass-name :test #'string=))
+     :java-class jclass)))))
+
+(defmethod mop::compute-class-precedence-list ((class java-class))
+  "Sort classes this way:
+   1. Java classes (but not java.lang.Object)
+   2. Java interfaces
+   3. java.lang.Object
+   4. other classes
+   Rationale:
+   1. Concrete classes are the most specific.
+   2. Then come interfaces.
+     So if a generic function is specialized both on an interface and a concrete class,
+     the concrete class comes first.
+   3. because everything is an Object.
+   4. to handle base CLOS classes.
+   Note: Java interfaces are not sorted among themselves in any way, so if a
+   gf is specialized on two different interfaces and you apply it to an object that
+   implements both, it is unspecified which method will be called."
+  (let ((cpl (call-next-method)))
+    (flet ((score (class)
+       (if (not (typep class 'java-class))
+     4
+     (cond
+       ((jcall (jmethod "java.lang.Object" "equals" "java.lang.Object")
+         (java-class-jclass class) +java-lang-object+) 3)
+       ((jclass-interface-p (java-class-jclass class)) 2)
+       (t 1)))))
+      (stable-sort cpl #'(lambda (x y)
+         (< (score x) (score y)))))))
     
 (defmethod make-instance ((class java-class) &rest initargs &key &allow-other-keys)