1 /*
   2  * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /**
  25  * @test
  26  * @bug 7196190
  27  * @summary Improve method of handling MethodHandles
  28  *
  29  * @run main/othervm ClassForNameTest
  30  */
  31 
  32 import java.lang.invoke.*;
  33 import java.lang.reflect.Method;
  34 import java.util.Arrays;
  35 
  36 public class ClassForNameTest {
  37     static final String NAME = ClassForNameTest.class.getName();
  38 
  39     public static void main(String[] args) throws Throwable {
  40         {
  41             final MethodType mt = MethodType.methodType(Class.class, String.class);
  42             final MethodHandle mh = MethodHandles.lookup()
  43                     .findStatic(Class.class, "forName", mt);
  44 
  45             Class.forName(NAME);
  46 
  47             mh.invoke(NAME);
  48             mh.bindTo(NAME).invoke();
  49             mh.invokeWithArguments(Arrays.asList(NAME));
  50             mh.invokeWithArguments(NAME);
  51             Class cls = (Class) mh.invokeExact(NAME);
  52         }
  53 
  54         {
  55             final Method fnMethod = Class.class.getMethod("forName", String.class);
  56             final MethodType mt = MethodType.methodType(Object.class, Object.class, Object[].class);
  57             final MethodHandle mh = MethodHandles.lookup()
  58                     .findVirtual(Method.class, "invoke", mt)
  59                     .bindTo(fnMethod);
  60 
  61             fnMethod.invoke(null, NAME);
  62 
  63             mh.bindTo(null).bindTo(new Object[]{NAME}).invoke();
  64             mh.invoke(null, new Object[]{NAME});
  65             mh.invokeWithArguments(null, new Object[]{NAME});
  66             mh.invokeWithArguments(Arrays.asList(null, new Object[]{NAME}));
  67             Object obj = mh.invokeExact((Object) null, new Object[]{NAME});
  68         }
  69 
  70         {
  71             final Method fnMethod = Class.class.getMethod("forName", String.class);
  72             final MethodType mt = MethodType.methodType(Object.class, Object.class, Object[].class);
  73 
  74             final MethodHandle mh = MethodHandles.lookup()
  75                     .bind(fnMethod, "invoke", mt);
  76 
  77             mh.bindTo(null).bindTo(new Object[]{NAME}).invoke();
  78             mh.invoke(null, new Object[]{NAME});
  79             mh.invokeWithArguments(null, NAME);
  80             mh.invokeWithArguments(Arrays.asList(null, NAME));
  81             Object obj = mh.invokeExact((Object) null, new Object[]{NAME});
  82         }
  83 
  84         {
  85             final Method fnMethod = Class.class.getMethod("forName", String.class);
  86             final MethodHandle mh = MethodHandles.lookup().unreflect(fnMethod);
  87 
  88             mh.bindTo(NAME).invoke();
  89             mh.invoke(NAME);
  90             mh.invokeWithArguments(NAME);
  91             mh.invokeWithArguments(Arrays.asList(NAME));
  92             Class cls = (Class) mh.invokeExact(NAME);
  93         }
  94 
  95         System.out.println("TEST PASSED");
  96     }
  97 }