1 /*
   2  * Copyright (c) 2001, 2013, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.internal.reflect;
  27 
  28 import java.lang.reflect.*;
  29 import sun.reflect.misc.ReflectUtil;
  30 
  31 /** Used only for the first few invocations of a Method; afterward,
  32     switches to bytecode-based implementation */
  33 
  34 class NativeMethodAccessorImpl extends MethodAccessorImpl {
  35     private final Method method;
  36     private DelegatingMethodAccessorImpl parent;
  37     private int numInvocations;
  38 
  39     NativeMethodAccessorImpl(Method method) {
  40         this.method = method;
  41     }
  42 
  43     public Object invoke(Object obj, Object[] args)
  44         throws IllegalArgumentException, InvocationTargetException
  45     {
  46         // We can't inflate methods belonging to vm-anonymous classes because
  47         // that kind of class can't be referred to by name, hence can't be
  48         // found from the generated bytecode.
  49         if (++numInvocations > ReflectionFactory.inflationThreshold()
  50                 && !method.getDeclaringClass().isHidden()) {
  51             MethodAccessorImpl acc = (MethodAccessorImpl)
  52                 new MethodAccessorGenerator().
  53                     generateMethod(method.getDeclaringClass(),
  54                                    method.getName(),
  55                                    method.getParameterTypes(),
  56                                    method.getReturnType(),
  57                                    method.getExceptionTypes(),
  58                                    method.getModifiers());
  59             parent.setDelegate(acc);
  60         }
  61 
  62         return invoke0(method, obj, args);
  63     }
  64 
  65     void setParent(DelegatingMethodAccessorImpl parent) {
  66         this.parent = parent;
  67     }
  68 
  69     private static native Object invoke0(Method m, Object obj, Object[] args);
  70 }