Wed, 20 Aug 2014 10:25:28 +0200
8044638: Tidy up Nashorn codebase for code standards
8055199: Tidy up Nashorn codebase for code standards (August 2014)
Reviewed-by: lagergren, sundar
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 */
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
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.
40 You may not use this file except in compliance with either the Apache
41 License or the BSD License.
43 If you choose to use this file in compliance with the Apache License, the
44 following notice applies to you:
46 You may obtain a copy of the Apache License at
48 http://www.apache.org/licenses/LICENSE-2.0
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.
56 If you choose to use this file in compliance with the BSD License, the
57 following notice applies to you:
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.
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 */
84 package jdk.internal.dynalink.beans;
86 import java.lang.invoke.MethodHandle;
87 import jdk.internal.dynalink.linker.GuardedInvocation;
89 /**
90 * Represents one component for a GuardedInvocation of a potentially composite operation of an
91 * {@link AbstractJavaLinker}. In addition to holding a guarded invocation, it holds semantic information about its
92 * guard. All guards produced in the AbstractJavaLinker are either "Class.isInstance()" or "getClass() == clazz"
93 * expressions. This allows choosing the most restrictive guard as the guard for the composition of two components.
94 * @author Attila Szegedi
95 * @version $Id: $
96 */
97 class GuardedInvocationComponent {
98 enum ValidationType {
99 NONE, // No guard; the operation can be linked unconditionally (quite rare); least strict.
100 INSTANCE_OF, // "validatorClass.isInstance(obj)" guard
101 EXACT_CLASS, // "obj.getClass() == validatorClass" guard; most strict.
102 IS_ARRAY, // "obj.getClass().isArray()"
103 }
105 private final GuardedInvocation guardedInvocation;
106 private final Validator validator;
108 GuardedInvocationComponent(final MethodHandle invocation) {
109 this(invocation, null, ValidationType.NONE);
110 }
112 GuardedInvocationComponent(final MethodHandle invocation, final MethodHandle guard, final ValidationType validationType) {
113 this(invocation, guard, null, validationType);
114 }
116 GuardedInvocationComponent(final MethodHandle invocation, final MethodHandle guard, final Class<?> validatorClass,
117 final ValidationType validationType) {
118 this(invocation, guard, new Validator(validatorClass, validationType));
119 }
121 GuardedInvocationComponent(final GuardedInvocation guardedInvocation, final Class<?> validatorClass,
122 final ValidationType validationType) {
123 this(guardedInvocation, new Validator(validatorClass, validationType));
124 }
126 GuardedInvocationComponent replaceInvocation(final MethodHandle newInvocation) {
127 return replaceInvocation(newInvocation, guardedInvocation.getGuard());
128 }
130 GuardedInvocationComponent replaceInvocation(final MethodHandle newInvocation, final MethodHandle newGuard) {
131 return new GuardedInvocationComponent(guardedInvocation.replaceMethods(newInvocation,
132 newGuard), validator);
133 }
135 private GuardedInvocationComponent(final MethodHandle invocation, final MethodHandle guard, final Validator validator) {
136 this(new GuardedInvocation(invocation, guard), validator);
137 }
139 private GuardedInvocationComponent(final GuardedInvocation guardedInvocation, final Validator validator) {
140 this.guardedInvocation = guardedInvocation;
141 this.validator = validator;
142 }
144 GuardedInvocation getGuardedInvocation() {
145 return guardedInvocation;
146 }
148 Class<?> getValidatorClass() {
149 return validator.validatorClass;
150 }
152 ValidationType getValidationType() {
153 return validator.validationType;
154 }
156 GuardedInvocationComponent compose(final MethodHandle compositeInvocation, final MethodHandle otherGuard,
157 final Class<?> otherValidatorClass, final ValidationType otherValidationType) {
158 final Validator compositeValidator = validator.compose(new Validator(otherValidatorClass, otherValidationType));
159 final MethodHandle compositeGuard = compositeValidator == validator ? guardedInvocation.getGuard() : otherGuard;
160 return new GuardedInvocationComponent(compositeInvocation, compositeGuard, compositeValidator);
161 }
163 private static class Validator {
164 /*private*/ final Class<?> validatorClass;
165 /*private*/ final ValidationType validationType;
167 Validator(final Class<?> validatorClass, final ValidationType validationType) {
168 this.validatorClass = validatorClass;
169 this.validationType = validationType;
170 }
172 Validator compose(final Validator other) {
173 if(other.validationType == ValidationType.NONE) {
174 return this;
175 }
176 switch(validationType) {
177 case NONE:
178 return other;
179 case INSTANCE_OF:
180 switch(other.validationType) {
181 case INSTANCE_OF:
182 if(isAssignableFrom(other)) {
183 return other;
184 } else if(other.isAssignableFrom(this)) {
185 return this;
186 }
187 break;
188 case EXACT_CLASS:
189 if(isAssignableFrom(other)) {
190 return other;
191 }
192 break;
193 case IS_ARRAY:
194 if(validatorClass.isArray()) {
195 return this;
196 }
197 break;
198 default:
199 throw new AssertionError();
200 }
201 break;
202 case EXACT_CLASS:
203 switch(other.validationType) {
204 case INSTANCE_OF:
205 if(other.isAssignableFrom(this)) {
206 return this;
207 }
208 break;
209 case EXACT_CLASS:
210 if(validatorClass == other.validatorClass) {
211 return this;
212 }
213 break;
214 case IS_ARRAY:
215 if(validatorClass.isArray()) {
216 return this;
217 }
218 break;
219 default:
220 throw new AssertionError();
221 }
222 break;
223 case IS_ARRAY:
224 switch(other.validationType) {
225 case INSTANCE_OF:
226 case EXACT_CLASS:
227 if(other.validatorClass.isArray()) {
228 return other;
229 }
230 break;
231 case IS_ARRAY:
232 return this;
233 default:
234 throw new AssertionError();
235 }
236 break;
237 default:
238 throw new AssertionError();
239 }
240 throw new AssertionError("Incompatible composition " + this + " vs " + other);
241 }
243 private boolean isAssignableFrom(final Validator other) {
244 return validatorClass.isAssignableFrom(other.validatorClass);
245 }
247 @Override
248 public String toString() {
249 return "Validator[" + validationType + (validatorClass == null ? "" : (" " + validatorClass.getName())) + "]";
250 }
251 }
252 }