6656586: Cursor.predefined is protected static mutable (findbugs)

Reviewed-by: hawtin, igor

src/share/classes/java/awt/Cursor.java

@@ -118,8 +118,18 @@ public class Cursor implements java.io.Serializable {
      */
     public static final int     MOVE_CURSOR                     = 13;
 
+    /**
+      * @deprecated As of JDK version 1.7, the {@link #getPredefinedCursor()}
+      * method should be used instead.
+      */
+    @Deprecated
     protected static Cursor predefined[] = new Cursor[14];
 
+    /**
+     * This field is a private replacement for 'predefined' array.
+     */
+    private final static Cursor[] predefinedPrivate = new Cursor[14];
+
     /* Localization names and default values */
     static final String[][] cursorProperties = {
         { "AWT.DefaultCursor", "Default Cursor" },
@@ -253,10 +263,15 @@ public class Cursor implements java.io.Serializable {
         if (type < Cursor.DEFAULT_CURSOR || type > Cursor.MOVE_CURSOR) {
             throw new IllegalArgumentException("illegal cursor type");
         }
+        Cursor c = predefinedPrivate[type];
+        if (c == null) {
+            predefinedPrivate[type] = c = new Cursor(type);
+        }
+        // fill 'predefined' array for backwards compatibility.
         if (predefined[type] == null) {
-            predefined[type] = new Cursor(type);
+            predefined[type] = c;
         }
-        return predefined[type];
+        return c;
     }
 
     /**

test/java/awt/Cursor/PredefinedPrivate/PredefinedPrivate.java

+/*
+ * Copyright 2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6656586
+ * @summary Test that Cursor.predefined array is not used in
+Cursor.getPredefinedCursor() method
+ * @author Artem Ananiev
+ * @run main PredefinedPrivate
+ */
+
+import java.awt.*;
+
+public class PredefinedPrivate {
+    public static void main(String args[]) {
+        new MyCursor();
+        if (Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR) instanceof MyCursor) {
+            throw new RuntimeException("Test FAILED: getPredefinedCursor() returned modified cursor");
+        }
+    }
+}
+
+class MyCursor extends Cursor {
+    public MyCursor() {
+        super(DEFAULT_CURSOR);
+        Cursor.predefined[DEFAULT_CURSOR] = this;
+    }
+}