Mon, 18 Feb 2013 16:00:15 +0100
8008371: Fix Dynalink compiler warnings and whitespace
Reviewed-by: jlaskey, 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 java.lang.invoke.MethodType;
88 import java.util.Iterator;
89 import java.util.LinkedList;
90 import java.util.List;
91 import jdk.internal.dynalink.beans.ApplicableOverloadedMethods.ApplicabilityTest;
92 import jdk.internal.dynalink.linker.LinkerServices;
93 import jdk.internal.dynalink.support.TypeUtilities;
95 /**
96 * Represents an overloaded method.
97 *
98 * @author Attila Szegedi
99 */
100 class OverloadedDynamicMethod extends DynamicMethod {
101 /**
102 * Holds a list of all methods.
103 */
104 private final LinkedList<MethodHandle> methods;
105 private final ClassLoader classLoader;
107 /**
108 * Creates a new overloaded dynamic method.
109 *
110 * @param clazz the class this method belongs to
111 * @param name the name of the method
112 */
113 OverloadedDynamicMethod(Class<?> clazz, String name) {
114 this(new LinkedList<MethodHandle>(), clazz.getClassLoader(), getClassAndMethodName(clazz, name));
115 }
117 private OverloadedDynamicMethod(LinkedList<MethodHandle> methods, ClassLoader classLoader, String name) {
118 super(name);
119 this.methods = methods;
120 this.classLoader = classLoader;
121 }
123 @Override
124 SimpleDynamicMethod getMethodForExactParamTypes(String paramTypes) {
125 final LinkedList<MethodHandle> matchingMethods = new LinkedList<>();
126 for(MethodHandle method: methods) {
127 if(typeMatchesDescription(paramTypes, method.type())) {
128 matchingMethods.add(method);
129 }
130 }
131 switch(matchingMethods.size()) {
132 case 0: {
133 return null;
134 }
135 case 1: {
136 final MethodHandle target = matchingMethods.get(0);
137 return new SimpleDynamicMethod(target, SimpleDynamicMethod.getMethodNameWithSignature(target, getName()));
138 }
139 default: {
140 throw new BootstrapMethodError("Can't choose among " + matchingMethods + " for argument types "
141 + paramTypes + " for method " + getName());
142 }
143 }
144 }
146 @Override
147 public MethodHandle getInvocation(final MethodType callSiteType, final LinkerServices linkerServices) {
148 // First, find all methods applicable to the call site by subtyping (JLS 15.12.2.2)
149 final ApplicableOverloadedMethods subtypingApplicables = getApplicables(callSiteType,
150 ApplicableOverloadedMethods.APPLICABLE_BY_SUBTYPING);
151 // Next, find all methods applicable by method invocation conversion to the call site (JLS 15.12.2.3).
152 final ApplicableOverloadedMethods methodInvocationApplicables = getApplicables(callSiteType,
153 ApplicableOverloadedMethods.APPLICABLE_BY_METHOD_INVOCATION_CONVERSION);
154 // Finally, find all methods applicable by variable arity invocation. (JLS 15.12.2.4).
155 final ApplicableOverloadedMethods variableArityApplicables = getApplicables(callSiteType,
156 ApplicableOverloadedMethods.APPLICABLE_BY_VARIABLE_ARITY);
158 // Find the methods that are maximally specific based on the call site signature
159 List<MethodHandle> maximallySpecifics = subtypingApplicables.findMaximallySpecificMethods();
160 if(maximallySpecifics.isEmpty()) {
161 maximallySpecifics = methodInvocationApplicables.findMaximallySpecificMethods();
162 if(maximallySpecifics.isEmpty()) {
163 maximallySpecifics = variableArityApplicables.findMaximallySpecificMethods();
164 }
165 }
167 // Now, get a list of the rest of the methods; those that are *not* applicable to the call site signature based
168 // on JLS rules. As paradoxical as that might sound, we have to consider these for dynamic invocation, as they
169 // might match more concrete types passed in invocations. That's why we provisionally call them "invokables".
170 // This is typical for very generic signatures at call sites. Typical example: call site specifies
171 // (Object, Object), and we have a method whose parameter types are (String, int). None of the JLS applicability
172 // rules will trigger, but we must consider the method, as it can be the right match for a concrete invocation.
173 @SuppressWarnings({ "unchecked", "rawtypes" })
174 final List<MethodHandle> invokables = (List)methods.clone();
175 invokables.removeAll(subtypingApplicables.getMethods());
176 invokables.removeAll(methodInvocationApplicables.getMethods());
177 invokables.removeAll(variableArityApplicables.getMethods());
178 for(final Iterator<MethodHandle> it = invokables.iterator(); it.hasNext();) {
179 final MethodHandle m = it.next();
180 if(!isApplicableDynamically(linkerServices, callSiteType, m)) {
181 it.remove();
182 }
183 }
185 // If no additional methods can apply at invocation time, and there's more than one maximally specific method
186 // based on call site signature, that is a link-time ambiguity. In a static scenario, javac would report an
187 // ambiguity error.
188 if(invokables.isEmpty() && maximallySpecifics.size() > 1) {
189 throw new BootstrapMethodError("Can't choose among " + maximallySpecifics + " for argument types "
190 + callSiteType);
191 }
193 // Merge them all.
194 invokables.addAll(maximallySpecifics);
195 switch(invokables.size()) {
196 case 0: {
197 // No overloads can ever match the call site type
198 return null;
199 }
200 case 1: {
201 // Very lucky, we ended up with a single candidate method handle based on the call site signature; we
202 // can link it very simply by delegating to a SimpleDynamicMethod.
203 final MethodHandle mh = invokables.iterator().next();
204 return new SimpleDynamicMethod(mh).getInvocation(callSiteType, linkerServices);
205 }
206 default: {
207 // We have more than one candidate. We have no choice but to link to a method that resolves overloads on
208 // every invocation (alternatively, we could opportunistically link the one method that resolves for the
209 // current arguments, but we'd need to install a fairly complex guard for that and when it'd fail, we'd
210 // go back all the way to candidate selection.
211 // TODO: cache per call site type
212 return new OverloadedMethod(invokables, this, callSiteType, linkerServices).getInvoker();
213 }
214 }
216 }
218 @Override
219 public boolean contains(MethodHandle mh) {
220 final MethodType type = mh.type();
221 for(MethodHandle method: methods) {
222 if(typesEqualNoReceiver(type, method.type())) {
223 return true;
224 }
225 }
226 return false;
227 }
229 private static boolean typesEqualNoReceiver(MethodType type1, MethodType type2) {
230 final int pc = type1.parameterCount();
231 if(pc != type2.parameterCount()) {
232 return false;
233 }
234 for(int i = 1; i < pc; ++i) { // i = 1: ignore receiver
235 if(type1.parameterType(i) != type2.parameterType(i)) {
236 return false;
237 }
238 }
239 return true;
240 }
242 ClassLoader getClassLoader() {
243 return classLoader;
244 }
246 private static boolean isApplicableDynamically(LinkerServices linkerServices, MethodType callSiteType,
247 MethodHandle m) {
248 final MethodType methodType = m.type();
249 final boolean varArgs = m.isVarargsCollector();
250 final int fixedArgLen = methodType.parameterCount() - (varArgs ? 1 : 0);
251 final int callSiteArgLen = callSiteType.parameterCount();
253 // Arity checks
254 if(varArgs) {
255 if(callSiteArgLen < fixedArgLen) {
256 return false;
257 }
258 } else if(callSiteArgLen != fixedArgLen) {
259 return false;
260 }
262 // Fixed arguments type checks, starting from 1, as receiver type doesn't participate
263 for(int i = 1; i < fixedArgLen; ++i) {
264 if(!isApplicableDynamically(linkerServices, callSiteType.parameterType(i), methodType.parameterType(i))) {
265 return false;
266 }
267 }
268 if(!varArgs) {
269 // Not vararg; both arity and types matched.
270 return true;
271 }
273 final Class<?> varArgArrayType = methodType.parameterType(fixedArgLen);
274 final Class<?> varArgType = varArgArrayType.getComponentType();
276 if(fixedArgLen == callSiteArgLen - 1) {
277 // Exactly one vararg; check both array type matching and array component type matching.
278 final Class<?> callSiteArgType = callSiteType.parameterType(fixedArgLen);
279 return isApplicableDynamically(linkerServices, callSiteArgType, varArgArrayType)
280 || isApplicableDynamically(linkerServices, callSiteArgType, varArgType);
281 }
283 // Either zero, or more than one vararg; check if all actual vararg types match the vararg array component type.
284 for(int i = fixedArgLen; i < callSiteArgLen; ++i) {
285 if(!isApplicableDynamically(linkerServices, callSiteType.parameterType(i), varArgType)) {
286 return false;
287 }
288 }
290 return true;
291 }
293 private static boolean isApplicableDynamically(LinkerServices linkerServices, Class<?> callSiteType,
294 Class<?> methodType) {
295 return TypeUtilities.isPotentiallyConvertible(callSiteType, methodType)
296 || linkerServices.canConvert(callSiteType, methodType);
297 }
299 private ApplicableOverloadedMethods getApplicables(MethodType callSiteType, ApplicabilityTest test) {
300 return new ApplicableOverloadedMethods(methods, callSiteType, test);
301 }
303 /**
304 * Add a method identified by a {@link SimpleDynamicMethod} to this overloaded method's set.
305 *
306 * @param method the method to add.
307 */
308 void addMethod(SimpleDynamicMethod method) {
309 addMethod(method.getTarget());
310 }
312 /**
313 * Add a method to this overloaded method's set.
314 *
315 * @param method a method to add
316 */
317 public void addMethod(MethodHandle method) {
318 methods.add(method);
319 }
320 }