1 /*

     2  * Copyright (c) 2010, 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 /*

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

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

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

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

    31  * license:

    32  */

    33 /*

    34    Copyright 2009-2013 Attila Szegedi

    35 

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

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

    38    choose either of the two at their discretion.

    39 

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

    41    License or the BSD License.

    42 

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

    44    following notice applies to you:

    45 

    46        You may obtain a copy of the Apache License at

    47 

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

    49 

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

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

    52        WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or

    53        implied. See the License for the specific language governing

    54        permissions and limitations under the License.

    55 

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

    57    following notice applies to you:

    58 

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

    60        modification, are permitted provided that the following conditions are

    61        met:

    62        * Redistributions of source code must retain the above copyright

    63          notice, this list of conditions and the following disclaimer.

    64        * Redistributions in binary form must reproduce the above copyright

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

    66          documentation and/or other materials provided with the distribution.

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

    68          contributors may be used to endorse or promote products derived from

    69          this software without specific prior written permission.

    70 

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

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

    73        TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

    74        PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER

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

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

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

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

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

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

    81        ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    82 */

    83 

    84 package jdk.internal.dynalink.beans;

    85 

    86 import java.lang.invoke.MethodHandle;

    87 import jdk.internal.dynalink.linker.GuardedInvocation;

    88 

    89 

    90 /**

    91  * Represents one component for a GuardedInvocation of a potentially composite operation of an

    92  * {@link AbstractJavaLinker}. In addition to holding a guarded invocation, it holds semantic information about its

    93  * guard. All guards produced in the AbstractJavaLinker are either "Class.isInstance()" or "getClass() == clazz"

    94  * expressions. This allows choosing the most restrictive guard as the guard for the composition of two components.

    95  * @author Attila Szegedi

    96  * @version $Id: $

    97  */

    98 class GuardedInvocationComponent {

    99     enum ValidationType {

   100         NONE, // No guard; the operation can be linked unconditionally (quite rare); least strict.

   101         INSTANCE_OF, // "validatorClass.isInstance(obj)" guard

   102         EXACT_CLASS, // "obj.getClass() == validatorClass" guard; most strict.

   103         IS_ARRAY, // "obj.getClass().isArray()"

   104     }

   105 

   106     private final GuardedInvocation guardedInvocation;

   107     private final Validator validator;

   108 

   109     GuardedInvocationComponent(MethodHandle invocation) {

   110         this(invocation, null, ValidationType.NONE);

   111     }

   112 

   113     GuardedInvocationComponent(MethodHandle invocation, MethodHandle guard, ValidationType validationType) {

   114         this(invocation, guard, null, validationType);

   115     }

   116 

   117     GuardedInvocationComponent(MethodHandle invocation, MethodHandle guard, Class<?> validatorClass,

   118             ValidationType validationType) {

   119         this(invocation, guard, new Validator(validatorClass, validationType));

   120     }

   121 

   122     GuardedInvocationComponent(GuardedInvocation guardedInvocation, Class<?> validatorClass,

   123             ValidationType validationType) {

   124         this(guardedInvocation, new Validator(validatorClass, validationType));

   125     }

   126 

   127     GuardedInvocationComponent replaceInvocation(MethodHandle newInvocation) {

   128         return replaceInvocation(newInvocation, guardedInvocation.getGuard());

   129     }

   130 

   131     GuardedInvocationComponent replaceInvocation(MethodHandle newInvocation, MethodHandle newGuard) {

   132         return new GuardedInvocationComponent(guardedInvocation.replaceMethods(newInvocation,

   133                 newGuard), validator);

   134     }

   135 

   136     private GuardedInvocationComponent(MethodHandle invocation, MethodHandle guard, Validator validator) {

   137         this(new GuardedInvocation(invocation, guard), validator);

   138     }

   139 

   140     private GuardedInvocationComponent(GuardedInvocation guardedInvocation, Validator validator) {

   141         this.guardedInvocation = guardedInvocation;

   142         this.validator = validator;

   143     }

   144 

   145     GuardedInvocation getGuardedInvocation() {

   146         return guardedInvocation;

   147     }

   148 

   149     Class<?> getValidatorClass() {

   150         return validator.validatorClass;

   151     }

   152 

   153     ValidationType getValidationType() {

   154         return validator.validationType;

   155     }

   156 

   157     GuardedInvocationComponent compose(MethodHandle compositeInvocation, MethodHandle otherGuard,

   158             Class<?> otherValidatorClass, ValidationType otherValidationType) {

   159         final Validator compositeValidator = validator.compose(new Validator(otherValidatorClass, otherValidationType));

   160         final MethodHandle compositeGuard = compositeValidator == validator ? guardedInvocation.getGuard() : otherGuard;

   161         return new GuardedInvocationComponent(compositeInvocation, compositeGuard, compositeValidator);

   162     }

   163 

   164     private static class Validator {

   165         /*private*/ final Class<?> validatorClass;

   166         /*private*/ final ValidationType validationType;

   167 

   168         Validator(Class<?> validatorClass, ValidationType validationType) {

   169             this.validatorClass = validatorClass;

   170             this.validationType = validationType;

   171         }

   172 

   173         Validator compose(Validator other) {

   174             if(other.validationType == ValidationType.NONE) {

   175                 return this;

   176             }

   177             switch(validationType) {

   178                 case NONE:

   179                     return other;

   180                 case INSTANCE_OF:

   181                     switch(other.validationType) {

   182                         case INSTANCE_OF:

   183                             if(isAssignableFrom(other)) {

   184                                 return other;

   185                             } else if(other.isAssignableFrom(this)) {

   186                                 return this;

   187                             }

   188                             break;

   189                         case EXACT_CLASS:

   190                             if(isAssignableFrom(other)) {

   191                                 return other;

   192                             }

   193                             break;

   194                         case IS_ARRAY:

   195                             if(validatorClass.isArray()) {

   196                                 return this;

   197                             }

   198                             break;

   199                         case NONE:

   200                             throw new AssertionError(); // Not possible

   201                     }

   202                     break;

   203                 case EXACT_CLASS:

   204                     switch(other.validationType) {

   205                         case INSTANCE_OF:

   206                             if(other.isAssignableFrom(this)) {

   207                                 return this;

   208                             }

   209                             break;

   210                         case EXACT_CLASS:

   211                             if(validatorClass == other.validatorClass) {

   212                                 return this;

   213                             }

   214                             break;

   215                         case IS_ARRAY:

   216                             if(validatorClass.isArray()) {

   217                                 return this;

   218                             }

   219                             break;

   220                         case NONE:

   221                             throw new AssertionError(); // Not possible

   222                     }

   223                     break;

   224                 case IS_ARRAY:

   225                     switch(other.validationType) {

   226                         case INSTANCE_OF:

   227                         case EXACT_CLASS:

   228                             if(other.validatorClass.isArray()) {

   229                                 return other;

   230                             }

   231                             break;

   232                         case IS_ARRAY:

   233                             return this;

   234                         case NONE:

   235                             throw new AssertionError(); // Not possible

   236                     }

   237                     break;

   238             }

   239             throw new AssertionError("Incompatible composition " + this + " vs " + other);

   240         }

   241 

   242         private boolean isAssignableFrom(Validator other) {

   243             return validatorClass.isAssignableFrom(other.validatorClass);

   244         }

   245 

   246         @Override

   247         public String toString() {

   248             return "Validator[" + validationType + (validatorClass == null ? "" : (" " + validatorClass.getName())) + "]";

   249         }

   250     }

   251 }