Mercurial > jdk8-mips64-public > nashorn / file revision

 /*

  * Copyright (c) 2010, 2013, 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

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the LICENSE file that accompanied this code.

  *

  * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 /*

  * This file is available under and governed by the GNU General Public

  * License version 2 only, as published by the Free Software Foundation.

  * However, the following notice accompanied the original version of this

  * file, and Oracle licenses the original version of this file under the BSD

  * license:

  */

 /*

    Copyright 2009-2013 Attila Szegedi

    Licensed under both the Apache License, Version 2.0 (the "Apache License")

    and the BSD License (the "BSD License"), with licensee being free to

    choose either of the two at their discretion.

    You may not use this file except in compliance with either the Apache

    License or the BSD License.

    If you choose to use this file in compliance with the Apache License, the

    following notice applies to you:

        You may obtain a copy of the Apache License at

            http://www.apache.org/licenses/LICENSE-2.0

        Unless required by applicable law or agreed to in writing, software

        distributed under the License is distributed on an "AS IS" BASIS,

        WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or

        implied. See the License for the specific language governing

        permissions and limitations under the License.

    If you choose to use this file in compliance with the BSD License, the

    following notice applies to you:

        Redistribution and use in source and binary forms, with or without

        modification, are permitted provided that the following conditions are

        met:

        * Redistributions of source code must retain the above copyright

          notice, this list of conditions and the following disclaimer.

        * Redistributions in binary form must reproduce the above copyright

          notice, this list of conditions and the following disclaimer in the

          documentation and/or other materials provided with the distribution.

        * Neither the name of the copyright holder nor the names of

          contributors may be used to endorse or promote products derived from

          this software without specific prior written permission.

        THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

        IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED

        TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

        PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER

        BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

        CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

        SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR

        BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,

        WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

        OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

        ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

 package jdk.internal.dynalink.beans;

 import java.lang.invoke.MethodHandle;

 import java.lang.invoke.MethodHandles;

 import java.lang.invoke.MethodType;

 import java.lang.reflect.Array;

 import java.lang.reflect.Constructor;

 import java.util.ArrayList;

 import java.util.List;

 import jdk.internal.dynalink.CallSiteDescriptor;

 import jdk.internal.dynalink.beans.GuardedInvocationComponent.ValidationType;

 import jdk.internal.dynalink.linker.GuardedInvocation;

 import jdk.internal.dynalink.linker.GuardingDynamicLinker;

 import jdk.internal.dynalink.linker.LinkRequest;

 import jdk.internal.dynalink.linker.LinkerServices;

 import jdk.internal.dynalink.linker.TypeBasedGuardingDynamicLinker;

 import jdk.internal.dynalink.support.Lookup;

 /**

  * Provides a linker for the {@link StaticClass} objects.

  * @author Attila Szegedi

  */

 class StaticClassLinker implements TypeBasedGuardingDynamicLinker {

     private final ClassValue<GuardingDynamicLinker> linkers = new ClassValue<GuardingDynamicLinker>() {

         @Override

         protected GuardingDynamicLinker computeValue(Class<?> clazz) {

             return new SingleClassStaticsLinker(clazz);

         }

     };

     private static class SingleClassStaticsLinker extends AbstractJavaLinker {

         private final DynamicMethod constructor;

         SingleClassStaticsLinker(Class<?> clazz) {

             super(clazz, IS_CLASS.bindTo(clazz));

             // Map "staticClassObject.class" to StaticClass.getRepresentedClass(). Some adventurous soul could subclass

             // StaticClass, so we use INSTANCE_OF validation instead of EXACT_CLASS.

             setPropertyGetter("class", GET_CLASS, ValidationType.INSTANCE_OF);

             constructor = createConstructorMethod(clazz);

         }

         /**

          * Creates a dynamic method containing all overloads of a class' public constructor

          * @param clazz the target class

          * @return a dynamic method containing all overloads of a class' public constructor. If the class has no public

          * constructors, returns null.

          */

         private static DynamicMethod createConstructorMethod(Class<?> clazz) {

             if(clazz.isArray()) {

                 final MethodHandle boundArrayCtor = ARRAY_CTOR.bindTo(clazz.getComponentType());

                 return new SimpleDynamicMethod(drop(boundArrayCtor.asType(boundArrayCtor.type().changeReturnType(

                         clazz))), clazz, "<init>");

             }

             final Constructor<?>[] ctrs = clazz.getConstructors();

             final List<MethodHandle> mhs = new ArrayList<>(ctrs.length);

             for(int i = 0; i < ctrs.length; ++i) {

                 mhs.add(drop(Lookup.PUBLIC.unreflectConstructor(ctrs[i])));

             }

             return createDynamicMethod(mhs, clazz, "<init>");

         }

         private static MethodHandle drop(MethodHandle mh) {

             return MethodHandles.dropArguments(mh, 0, StaticClass.class);

         }

         @Override

         FacetIntrospector createFacetIntrospector() {

             return new StaticClassIntrospector(clazz);

         }

         @Override

         public GuardedInvocation getGuardedInvocation(LinkRequest request, LinkerServices linkerServices)

                 throws Exception {

             final GuardedInvocation gi = super.getGuardedInvocation(request, linkerServices);

             if(gi != null) {

                 return gi;

             }

             final CallSiteDescriptor desc = request.getCallSiteDescriptor();

             final String op = desc.getNameToken(CallSiteDescriptor.OPERATOR);

             final MethodType methodType = desc.getMethodType();

             if("new" == op && constructor != null) {

                 final MethodHandle ctorInvocation = constructor.getInvocation(methodType, linkerServices);

                 if(ctorInvocation != null) {

                     return new GuardedInvocation(ctorInvocation, getClassGuard(methodType));

                 }

             }

             return null;

         }

     }

     @Override

     public GuardedInvocation getGuardedInvocation(LinkRequest request, LinkerServices linkerServices) throws Exception {

         final Object receiver = request.getReceiver();

         if(receiver instanceof StaticClass) {

             return linkers.get(((StaticClass)receiver).getRepresentedClass()).getGuardedInvocation(request,

                     linkerServices);

         }

         return null;

     }

     @Override

     public boolean canLinkType(Class<?> type) {

         return type == StaticClass.class;

     }

     /*private*/ static final MethodHandle GET_CLASS = new Lookup(MethodHandles.lookup()).findVirtual(StaticClass.class,

             "getRepresentedClass", MethodType.methodType(Class.class));

     /*private*/ static final MethodHandle IS_CLASS = new Lookup(MethodHandles.lookup()).findStatic(StaticClassLinker.class,

             "isClass", MethodType.methodType(Boolean.TYPE, Class.class, Object.class));

     /*private*/ static final MethodHandle ARRAY_CTOR = Lookup.PUBLIC.findStatic(Array.class, "newInstance",

             MethodType.methodType(Object.class, Class.class, int.class));

     @SuppressWarnings("unused")

     private static boolean isClass(Class<?> clazz, Object obj) {

         return obj instanceof StaticClass && ((StaticClass)obj).getRepresentedClass() == clazz;

     }

 }