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 Redistribution and use in source and binary forms, with or without 37 modification, are permitted provided that the following conditions are 38 met: 39 * Redistributions of source code must retain the above copyright 40 notice, this list of conditions and the following disclaimer. 41 * Redistributions in binary form must reproduce the above copyright 42 notice, this list of conditions and the following disclaimer in the 43 documentation and/or other materials provided with the distribution. 44 * Neither the name of the copyright holder nor the names of 45 contributors may be used to endorse or promote products derived from 46 this software without specific prior written permission. 47 48 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 49 IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 50 TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 51 PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER 52 BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 53 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 54 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 55 BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 56 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 57 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 58 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 59 */ 60 61 package jdk.dynalink; 62 63 import java.lang.invoke.MethodHandle; 64 import java.lang.invoke.MethodHandles; 65 import java.lang.invoke.MethodHandles.Lookup; 66 import java.lang.invoke.MethodType; 67 import java.util.Objects; 68 import java.util.function.Supplier; 69 import jdk.dynalink.linker.ConversionComparator.Comparison; 70 import jdk.dynalink.linker.GuardedInvocation; 71 import jdk.dynalink.linker.GuardingDynamicLinker; 72 import jdk.dynalink.linker.LinkRequest; 73 import jdk.dynalink.linker.LinkerServices; 74 import jdk.dynalink.linker.MethodHandleTransformer; 75 76 /** 77 * Default implementation of the {@link LinkerServices} interface. 78 */ 79 final class LinkerServicesImpl implements LinkerServices { 80 private static final ThreadLocal<SecureLookupSupplier> threadLookupSupplier = new ThreadLocal<>(); 81 82 private final TypeConverterFactory typeConverterFactory; 83 private final GuardingDynamicLinker topLevelLinker; 84 private final MethodHandleTransformer internalObjectsFilter; 85 86 /** 87 * Creates a new linker services object. 88 * 89 * @param typeConverterFactory the type converter factory exposed by the services. 90 * @param topLevelLinker the top level linker used by the services. 91 * @param internalObjectsFilter a method handle transformer that is supposed to act as the implementation of this 92 * services' {@link #filterInternalObjects(java.lang.invoke.MethodHandle)} method. 93 */ LinkerServicesImpl(final TypeConverterFactory typeConverterFactory, final GuardingDynamicLinker topLevelLinker, final MethodHandleTransformer internalObjectsFilter)94 LinkerServicesImpl(final TypeConverterFactory typeConverterFactory, 95 final GuardingDynamicLinker topLevelLinker, final MethodHandleTransformer internalObjectsFilter) { 96 this.typeConverterFactory = typeConverterFactory; 97 this.topLevelLinker = topLevelLinker; 98 this.internalObjectsFilter = internalObjectsFilter; 99 } 100 101 @Override canConvert(final Class<?> from, final Class<?> to)102 public boolean canConvert(final Class<?> from, final Class<?> to) { 103 return typeConverterFactory.canConvert(from, to); 104 } 105 106 @Override asType(final MethodHandle handle, final MethodType fromType)107 public MethodHandle asType(final MethodHandle handle, final MethodType fromType) { 108 return typeConverterFactory.asType(handle, fromType); 109 } 110 111 @Override getTypeConverter(final Class<?> sourceType, final Class<?> targetType)112 public MethodHandle getTypeConverter(final Class<?> sourceType, final Class<?> targetType) { 113 return typeConverterFactory.getTypeConverter(sourceType, targetType); 114 } 115 116 @Override compareConversion(final Class<?> sourceType, final Class<?> targetType1, final Class<?> targetType2)117 public Comparison compareConversion(final Class<?> sourceType, final Class<?> targetType1, final Class<?> targetType2) { 118 return typeConverterFactory.compareConversion(sourceType, targetType1, targetType2); 119 } 120 121 /** 122 * Used to marshal a checked exception out of Supplier.get() in getGuardedInvocation. 123 */ 124 private static class LinkerException extends RuntimeException { 125 private static final long serialVersionUID = 1L; 126 LinkerException(final Exception cause)127 public LinkerException(final Exception cause) { 128 super(null, cause, true, false); 129 } 130 } 131 132 @Override getGuardedInvocation(final LinkRequest linkRequest)133 public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest) throws Exception { 134 try { 135 return getWithLookupInternal(() -> { 136 try { 137 return topLevelLinker.getGuardedInvocation(linkRequest, this); 138 } catch (final RuntimeException e) { 139 throw e; 140 } catch (final Exception e) { 141 throw new LinkerException(e); 142 } 143 }, linkRequest.getCallSiteDescriptor()); 144 } catch (final LinkerException e) { 145 throw (Exception)e.getCause(); 146 } 147 } 148 149 @Override 150 public MethodHandle filterInternalObjects(final MethodHandle target) { 151 return internalObjectsFilter != null ? internalObjectsFilter.transform(target) : target; 152 } 153 154 @Override 155 public <T> T getWithLookup(final Supplier<T> operation, final SecureLookupSupplier lookupSupplier) { 156 return getWithLookupInternal( 157 Objects.requireNonNull(operation, "action"), 158 Objects.requireNonNull(lookupSupplier, "lookupSupplier")); 159 } 160 161 private static <T> T getWithLookupInternal(final Supplier<T> operation, final SecureLookupSupplier lookupSupplier) { 162 final SecureLookupSupplier prevLookupSupplier = threadLookupSupplier.get(); 163 final boolean differ = prevLookupSupplier != lookupSupplier; 164 if (differ) { 165 threadLookupSupplier.set(lookupSupplier); 166 } 167 try { 168 return operation.get(); 169 } finally { 170 if (differ) { 171 threadLookupSupplier.set(prevLookupSupplier); 172 } 173 } 174 } 175 176 static Lookup getCurrentLookup() { 177 final SecureLookupSupplier lookupSupplier = threadLookupSupplier.get(); 178 if (lookupSupplier != null) { 179 return lookupSupplier.getLookup(); 180 } 181 return MethodHandles.publicLookup(); 182 } 183 } 184