1 /* 2 * Copyright (c) 2005, 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 package com.sun.tools.javac.code; 26 27 import java.lang.annotation.Annotation; 28 import java.lang.annotation.Inherited; 29 import java.lang.reflect.InvocationTargetException; 30 import java.lang.reflect.Method; 31 32 import javax.lang.model.AnnotatedConstruct; 33 34 import com.sun.tools.javac.model.AnnotationProxyMaker; 35 import com.sun.tools.javac.util.List; 36 import com.sun.tools.javac.util.ListBuffer; 37 38 /** 39 * Common super type for annotated constructs such as Types and Symbols. 40 * 41 * This class should *not* contain any fields since it would have a significant 42 * impact on the javac memory footprint. 43 * 44 * <p><b>This is NOT part of any supported API. 45 * If you write code that depends on this, you do so at your own 46 * risk. This code and its internal interfaces are subject to change 47 * or deletion without notice.</b></p> 48 */ 49 public abstract class AnnoConstruct implements AnnotatedConstruct { 50 51 52 // Override to enforce a narrower return type. 53 @Override getAnnotationMirrors()54 public abstract List<? extends Attribute.Compound> getAnnotationMirrors(); 55 56 57 // This method is part of the javax.lang.model API, do not use this in javac code. getAttribute(Class<A> annoType)58 protected <A extends Annotation> Attribute.Compound getAttribute(Class<A> annoType) { 59 String name = annoType.getName(); 60 61 for (Attribute.Compound anno : getAnnotationMirrors()) { 62 if (name.equals(anno.type.tsym.flatName().toString())) 63 return anno; 64 } 65 66 return null; 67 } 68 69 70 @SuppressWarnings("unchecked") getInheritedAnnotations(Class<A> annoType)71 protected <A extends Annotation> A[] getInheritedAnnotations(Class<A> annoType) { 72 return (A[]) java.lang.reflect.Array.newInstance(annoType, 0); // annoType is the Class for A 73 } 74 75 76 // This method is part of the javax.lang.model API, do not use this in javac code. getAnnotationsByType(Class<A> annoType)77 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annoType) { 78 79 if (!annoType.isAnnotation()) 80 throw new IllegalArgumentException("Not an annotation type: " 81 + annoType); 82 // If annoType does not declare a container this is equivalent to wrapping 83 // getAnnotation(...) in an array. 84 Class <? extends Annotation> containerType = getContainer(annoType); 85 if (containerType == null) { 86 A res = getAnnotation(annoType); 87 int size = res == null ? 0 : 1; 88 89 @SuppressWarnings("unchecked") // annoType is the Class for A 90 A[] arr = (A[])java.lang.reflect.Array.newInstance(annoType, size); 91 if (res != null) 92 arr[0] = res; 93 return arr; 94 } 95 96 // So we have a containing type 97 String annoTypeName = annoType.getName(); 98 String containerTypeName = containerType.getName(); 99 int directIndex = -1, containerIndex = -1; 100 Attribute.Compound direct = null, container = null; 101 // Find directly (explicit or implicit) present annotations 102 int index = -1; 103 for (Attribute.Compound attribute : getAnnotationMirrors()) { 104 index++; 105 if (attribute.type.tsym.flatName().contentEquals(annoTypeName)) { 106 directIndex = index; 107 direct = attribute; 108 } else if(containerTypeName != null && 109 attribute.type.tsym.flatName().contentEquals(containerTypeName)) { 110 containerIndex = index; 111 container = attribute; 112 } 113 } 114 115 // Deal with inherited annotations 116 if (direct == null && container == null && 117 annoType.isAnnotationPresent(Inherited.class)) 118 return getInheritedAnnotations(annoType); 119 120 Attribute.Compound[] contained = unpackContained(container); 121 122 // In case of an empty legacy container we might need to look for 123 // inherited annos as well 124 if (direct == null && contained.length == 0 && 125 annoType.isAnnotationPresent(Inherited.class)) 126 return getInheritedAnnotations(annoType); 127 128 int size = (direct == null ? 0 : 1) + contained.length; 129 @SuppressWarnings("unchecked") // annoType is the Class for A 130 A[] arr = (A[])java.lang.reflect.Array.newInstance(annoType, size); 131 132 // if direct && container, which is first? 133 int insert = -1; 134 int length = arr.length; 135 if (directIndex >= 0 && containerIndex >= 0) { 136 if (directIndex < containerIndex) { 137 arr[0] = AnnotationProxyMaker.generateAnnotation(direct, annoType); 138 insert = 1; 139 } else { 140 arr[arr.length - 1] = AnnotationProxyMaker.generateAnnotation(direct, annoType); 141 insert = 0; 142 length--; 143 } 144 } else if (directIndex >= 0) { 145 arr[0] = AnnotationProxyMaker.generateAnnotation(direct, annoType); 146 return arr; 147 } else { 148 // Only container 149 insert = 0; 150 } 151 152 for (int i = 0; i + insert < length; i++) 153 arr[insert + i] = AnnotationProxyMaker.generateAnnotation(contained[i], annoType); 154 155 return arr; 156 } 157 unpackContained(Attribute.Compound container)158 private Attribute.Compound[] unpackContained(Attribute.Compound container) { 159 // Pack them in an array 160 Attribute[] contained0 = null; 161 if (container != null) 162 contained0 = unpackAttributes(container); 163 ListBuffer<Attribute.Compound> compounds = new ListBuffer<>(); 164 if (contained0 != null) { 165 for (Attribute a : contained0) 166 if (a instanceof Attribute.Compound) 167 compounds = compounds.append((Attribute.Compound)a); 168 } 169 return compounds.toArray(new Attribute.Compound[compounds.size()]); 170 } 171 172 // This method is part of the javax.lang.model API, do not use this in javac code. getAnnotation(Class<A> annoType)173 public <A extends Annotation> A getAnnotation(Class<A> annoType) { 174 175 if (!annoType.isAnnotation()) 176 throw new IllegalArgumentException("Not an annotation type: " + annoType); 177 178 Attribute.Compound c = getAttribute(annoType); 179 return c == null ? null : AnnotationProxyMaker.generateAnnotation(c, annoType); 180 } 181 182 // Needed to unpack the runtime view of containing annotations 183 private static final Class<? extends Annotation> REPEATABLE_CLASS = initRepeatable(); 184 private static final Method VALUE_ELEMENT_METHOD = initValueElementMethod(); 185 initRepeatable()186 private static Class<? extends Annotation> initRepeatable() { 187 try { 188 // Repeatable will not be available when bootstrapping on 189 // JDK 7 so use a reflective lookup instead of a class 190 // literal for Repeatable.class. 191 return Class.forName("java.lang.annotation.Repeatable").asSubclass(Annotation.class); 192 } catch (ClassNotFoundException | SecurityException e) { 193 return null; 194 } 195 } 196 initValueElementMethod()197 private static Method initValueElementMethod() { 198 if (REPEATABLE_CLASS == null) 199 return null; 200 201 Method m = null; 202 try { 203 m = REPEATABLE_CLASS.getMethod("value"); 204 if (m != null) 205 m.setAccessible(true); 206 return m; 207 } catch (NoSuchMethodException e) { 208 return null; 209 } 210 } 211 212 213 // Helper to getAnnotationsByType getContainer(Class<? extends Annotation> annoType)214 private static Class<? extends Annotation> getContainer(Class<? extends Annotation> annoType) { 215 // Since we can not refer to java.lang.annotation.Repeatable until we are 216 // bootstrapping with java 8 we need to get the Repeatable annotation using 217 // reflective invocations instead of just using its type and element method. 218 if (REPEATABLE_CLASS != null && 219 VALUE_ELEMENT_METHOD != null) { 220 // Get the Repeatable instance on the annotations declaration 221 Annotation repeatable = (Annotation)annoType.getAnnotation(REPEATABLE_CLASS); 222 if (repeatable != null) { 223 try { 224 // Get the value element, it should be a class 225 // indicating the containing annotation type 226 @SuppressWarnings("unchecked") 227 Class<? extends Annotation> containerType = (Class)VALUE_ELEMENT_METHOD.invoke(repeatable); 228 if (containerType == null) 229 return null; 230 231 return containerType; 232 } catch (ClassCastException | IllegalAccessException | InvocationTargetException e) { 233 return null; 234 } 235 } 236 } 237 return null; 238 } 239 240 241 // Helper to getAnnotationsByType unpackAttributes(Attribute.Compound container)242 private static Attribute[] unpackAttributes(Attribute.Compound container) { 243 // We now have an instance of the container, 244 // unpack it returning an instance of the 245 // contained type or null 246 return ((Attribute.Array)container.member(container.type.tsym.name.table.names.value)).values; 247 } 248 249 } 250