Automatic merge of jdk:master into master

Author: duke

src/java.base/share/classes/java/lang/reflect/Method.java

@@ -95,6 +95,8 @@ public final class Method extends Executable {
     // If this branching structure would ever contain cycles, deadlocks can
     // occur in annotation code.
     private Method              root;
+    // Hash code of this object
+    private int                 hash;
 
     // Generics infrastructure
     private String getGenericSignature() {return signature;}
@@ -381,7 +383,13 @@ public boolean equals(Object obj) {
      * method's declaring class name and the method's name.
      */
     public int hashCode() {
-        return getDeclaringClass().getName().hashCode() ^ getName().hashCode();
+        int hc = hash;
+
+        if (hc == 0) {
+            hc = hash = getDeclaringClass().getName().hashCode() ^ getName()
+                .hashCode();
+        }
+        return hc;
     }
 
     /**

test/micro/org/openjdk/bench/java/lang/reflect/MethodBenchmark.java

@@ -36,8 +36,9 @@
 import org.openjdk.jmh.annotations.Warmup;
 
 /**
- * Benchmark measuring the speed of Method/Method.getExceptionTypes() and
- * getParameterTypes(), in cases where the result array is length zero.
+ * Benchmark measuring the speed of Method/Method.getExceptionTypes(),
+ * getParameterTypes() in cases where the result array is length zero,
+ * and hashCode().
  */
 @BenchmarkMode(Mode.AverageTime)
 @State(Scope.Benchmark)
@@ -50,6 +51,7 @@ public class MethodBenchmark {
     Method emptyParametersMethod;
     Method oneExceptionMethod;
     Method oneParameterMethod;
+    Method hashCodeMethod;
 
     public MethodBenchmark() {
         try {
@@ -58,6 +60,8 @@ public MethodBenchmark() {
 
             emptyExceptionsMethod = emptyParametersMethod;
             oneExceptionMethod = oneParameterMethod;
+
+            hashCodeMethod = String.class.getDeclaredMethod("toString");
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
@@ -82,4 +86,9 @@ public Object[] getParameterTypes() throws Exception {
     public Object[] getParameterTypesEmpty() throws Exception {
         return emptyParametersMethod.getParameterTypes();
     }
+
+    @Benchmark
+    public int getMethodHashCode() {
+        return hashCodeMethod.hashCode();
+    }
 }