LinkerServicesImpl.java revision 1645:15d52fdd9168
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 84package jdk.dynalink; 85 86import java.lang.invoke.MethodHandle; 87import java.lang.invoke.MethodHandles; 88import java.lang.invoke.MethodHandles.Lookup; 89import java.lang.invoke.MethodType; 90import java.util.Objects; 91import java.util.function.Supplier; 92import jdk.dynalink.linker.ConversionComparator.Comparison; 93import jdk.dynalink.linker.GuardedInvocation; 94import jdk.dynalink.linker.GuardingDynamicLinker; 95import jdk.dynalink.linker.LinkRequest; 96import jdk.dynalink.linker.LinkerServices; 97import jdk.dynalink.linker.MethodHandleTransformer; 98 99/** 100 * Default implementation of the {@link LinkerServices} interface. 101 */ 102final class LinkerServicesImpl implements LinkerServices { 103 private static final ThreadLocal<SecureLookupSupplier> threadLookupSupplier = new ThreadLocal<>(); 104 105 private final TypeConverterFactory typeConverterFactory; 106 private final GuardingDynamicLinker topLevelLinker; 107 private final MethodHandleTransformer internalObjectsFilter; 108 109 /** 110 * Creates a new linker services object. 111 * 112 * @param typeConverterFactory the type converter factory exposed by the services. 113 * @param topLevelLinker the top level linker used by the services. 114 * @param internalObjectsFilter a method handle transformer that is supposed to act as the implementation of this 115 * services' {@link #filterInternalObjects(java.lang.invoke.MethodHandle)} method. 116 */ 117 LinkerServicesImpl(final TypeConverterFactory typeConverterFactory, 118 final GuardingDynamicLinker topLevelLinker, final MethodHandleTransformer internalObjectsFilter) { 119 this.typeConverterFactory = typeConverterFactory; 120 this.topLevelLinker = topLevelLinker; 121 this.internalObjectsFilter = internalObjectsFilter; 122 } 123 124 @Override 125 public boolean canConvert(final Class<?> from, final Class<?> to) { 126 return typeConverterFactory.canConvert(from, to); 127 } 128 129 @Override 130 public MethodHandle asType(final MethodHandle handle, final MethodType fromType) { 131 return typeConverterFactory.asType(handle, fromType); 132 } 133 134 @Override 135 public MethodHandle getTypeConverter(final Class<?> sourceType, final Class<?> targetType) { 136 return typeConverterFactory.getTypeConverter(sourceType, targetType); 137 } 138 139 @Override 140 public Comparison compareConversion(final Class<?> sourceType, final Class<?> targetType1, final Class<?> targetType2) { 141 return typeConverterFactory.compareConversion(sourceType, targetType1, targetType2); 142 } 143 144 /** 145 * Used to marshal a checked exception out of Supplier.get() in getGuardedInvocation. 146 */ 147 private static class LinkerException extends RuntimeException { 148 private static final long serialVersionUID = 1L; 149 150 public LinkerException(final Exception cause) { 151 super(null, cause, true, false); 152 } 153 } 154 155 @Override 156 public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest) throws Exception { 157 try { 158 return getWithLookupInternal(() -> { 159 try { 160 return topLevelLinker.getGuardedInvocation(linkRequest, this); 161 } catch (final RuntimeException e) { 162 throw e; 163 } catch (final Exception e) { 164 throw new LinkerException(e); 165 } 166 }, linkRequest.getCallSiteDescriptor()); 167 } catch (final LinkerException e) { 168 throw (Exception)e.getCause(); 169 } 170 } 171 172 @Override 173 public MethodHandle filterInternalObjects(final MethodHandle target) { 174 return internalObjectsFilter != null ? internalObjectsFilter.transform(target) : target; 175 } 176 177 @Override 178 public <T> T getWithLookup(final Supplier<T> operation, final SecureLookupSupplier lookupSupplier) { 179 return getWithLookupInternal( 180 Objects.requireNonNull(operation, "action"), 181 Objects.requireNonNull(lookupSupplier, "lookupSupplier")); 182 } 183 184 private static <T> T getWithLookupInternal(final Supplier<T> operation, final SecureLookupSupplier lookupSupplier) { 185 final SecureLookupSupplier prevLookupSupplier = threadLookupSupplier.get(); 186 final boolean differ = prevLookupSupplier != lookupSupplier; 187 if (differ) { 188 threadLookupSupplier.set(lookupSupplier); 189 } 190 try { 191 return operation.get(); 192 } finally { 193 if (differ) { 194 threadLookupSupplier.set(prevLookupSupplier); 195 } 196 } 197 } 198 199 static Lookup getCurrentLookup() { 200 final SecureLookupSupplier lookupSupplier = threadLookupSupplier.get(); 201 if (lookupSupplier != null) { 202 return lookupSupplier.getLookup(); 203 } 204 return MethodHandles.publicLookup(); 205 } 206} 207