src/java.base/share/classes/java/io/ObjectStreamClass.java

rev 53109 : [mq]: 6996807-FieldReflectorKey-hash-code-compuation-can-be-improved

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 1996, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2019, Oracle and/or its affiliates. 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.  Oracle designates this

@@ -2273,26 +2273,26 @@
      * FieldReflector cache lookup key.  Keys are considered equal if they
      * refer to the same class and equivalent field formats.
      */
     private static class FieldReflectorKey extends WeakReference<Class<?>> {
 
-        private final String sigs;
+        private final String[] sigs;
         private final int hash;
         private final boolean nullClass;
 
         FieldReflectorKey(Class<?> cl, ObjectStreamField[] fields,
                           ReferenceQueue<Class<?>> queue)
         {
             super(cl, queue);
             nullClass = (cl == null);
-            StringBuilder sbuf = new StringBuilder();
+            sigs = new String[2 * fields.length];
             for (int i = 0; i < fields.length; i++) {
                 ObjectStreamField f = fields[i];
-                sbuf.append(f.getName()).append(f.getSignature());
+                sigs[2 * i] = f.getName();
+                sigs[2 * i + 1] = f.getSignature();
             }
-            sigs = sbuf.toString();
-            hash = System.identityHashCode(cl) + sigs.hashCode();
+            hash = System.identityHashCode(cl) + Arrays.hashCode(sigs);
         }
 
         public int hashCode() {
             return hash;
         }

@@ -2306,11 +2306,11 @@
                 FieldReflectorKey other = (FieldReflectorKey) obj;
                 Class<?> referent;
                 return (nullClass ? other.nullClass
                                   : ((referent = get()) != null) &&
                                     (referent == other.get())) &&
-                    sigs.equals(other.sigs);
+                    Arrays.equals(sigs, other.sigs);
             } else {
                 return false;
             }
         }
     }