1 /* 2 * Copyright (c) 2003, 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 package sun.reflect.annotation; 27 28 import sun.misc.JavaLangAccess; 29 30 import java.lang.annotation.*; 31 import java.lang.reflect.*; 32 import java.util.*; 33 import java.security.AccessController; 34 import java.security.PrivilegedAction; 35 36 /** 37 * Represents an annotation type at run time. Used to type-check annotations 38 * and apply member defaults. 39 * 40 * @author Josh Bloch 41 * @since 1.5 42 */ 43 public class AnnotationType { 44 /** 45 * Member name -> type mapping. Note that primitive types 46 * are represented by the class objects for the corresponding wrapper 47 * types. This matches the return value that must be used for a 48 * dynamic proxy, allowing for a simple isInstance test. 49 */ 50 private final Map<String, Class<?>> memberTypes; 51 52 /** 53 * Member name -> default value mapping. 54 */ 55 private final Map<String, Object> memberDefaults; 56 57 /** 58 * Member name -> Method object mapping. This (and its assoicated 59 * accessor) are used only to generate AnnotationTypeMismatchExceptions. 60 */ 61 private final Map<String, Method> members; 62 63 /** 64 * The retention policy for this annotation type. 65 */ 66 private final RetentionPolicy retention; 67 68 /** 69 * Whether this annotation type is inherited. 70 */ 71 private final boolean inherited; 72 73 /** 74 * Returns an AnnotationType instance for the specified annotation type. 75 * 76 * @throw IllegalArgumentException if the specified class object for 77 * does not represent a valid annotation type 78 */ 79 public static AnnotationType getInstance( 80 Class<? extends Annotation> annotationClass) 81 { 82 JavaLangAccess jla = sun.misc.SharedSecrets.getJavaLangAccess(); 83 AnnotationType result = jla.getAnnotationType(annotationClass); // volatile read 84 if (result == null) { 85 result = new AnnotationType(annotationClass); 86 // try to CAS the AnnotationType: null -> result 87 if (!jla.casAnnotationType(annotationClass, null, result)) { 88 // somebody was quicker -> read it's result 89 result = jla.getAnnotationType(annotationClass); 90 assert result != null; 91 } 92 } 93 94 return result; 95 } 96 97 /** 98 * Sole constructor. 99 * 100 * @param annotationClass the class object for the annotation type 101 * @throw IllegalArgumentException if the specified class object for 102 * does not represent a valid annotation type 103 */ 104 private AnnotationType(final Class<? extends Annotation> annotationClass) { 105 if (!annotationClass.isAnnotation()) 106 throw new IllegalArgumentException("Not an annotation type"); 107 108 // Initialize memberTypes and defaultValues 109 Method[] methods = 110 AccessController.doPrivileged(new PrivilegedAction<Method[]>() { 111 public Method[] run() { 112 Method[] methods = annotationClass.getDeclaredMethods(); 113 AccessibleObject.setAccessible(methods, true); 114 return methods; 115 } 116 }); 117 118 memberTypes = new HashMap<String,Class<?>>(methods.length+1, 1.0f); 119 memberDefaults = new HashMap<String, Object>(0); 120 members = new HashMap<String, Method>(methods.length+1, 1.0f); 121 122 for (Method method : methods) { 123 if (method.getParameterTypes().length != 0) 124 throw new IllegalArgumentException(method + " has params"); 125 String name = method.getName(); 126 Class<?> type = method.getReturnType(); 127 memberTypes.put(name, invocationHandlerReturnType(type)); 128 members.put(name, method); 129 130 Object defaultValue = method.getDefaultValue(); 131 if (defaultValue != null) 132 memberDefaults.put(name, defaultValue); 133 } 134 135 // Initialize retention, & inherited fields. Special treatment 136 // of the corresponding annotation types breaks infinite recursion. 137 if (annotationClass != Retention.class && 138 annotationClass != Inherited.class) { 139 JavaLangAccess jla = sun.misc.SharedSecrets.getJavaLangAccess(); 140 Map<Class<? extends Annotation>, Annotation> metaAnnotations = 141 AnnotationParser.parseSelectAnnotations( 142 jla.getRawClassAnnotations(annotationClass), 143 jla.getConstantPool(annotationClass), 144 annotationClass, 145 Retention.class, Inherited.class 146 ); 147 Retention ret = (Retention) metaAnnotations.get(Retention.class); 148 retention = (ret == null ? RetentionPolicy.CLASS : ret.value()); 149 inherited = metaAnnotations.containsKey(Inherited.class); 150 } 151 else { 152 retention = RetentionPolicy.RUNTIME; 153 inherited = false; 154 } 155 } 156 157 /** 158 * Returns the type that must be returned by the invocation handler 159 * of a dynamic proxy in order to have the dynamic proxy return 160 * the specified type (which is assumed to be a legal member type 161 * for an annotation). 162 */ 163 public static Class<?> invocationHandlerReturnType(Class<?> type) { 164 // Translate primitives to wrappers 165 if (type == byte.class) 166 return Byte.class; 167 if (type == char.class) 168 return Character.class; 169 if (type == double.class) 170 return Double.class; 171 if (type == float.class) 172 return Float.class; 173 if (type == int.class) 174 return Integer.class; 175 if (type == long.class) 176 return Long.class; 177 if (type == short.class) 178 return Short.class; 179 if (type == boolean.class) 180 return Boolean.class; 181 182 // Otherwise, just return declared type 183 return type; 184 } 185 186 /** 187 * Returns member types for this annotation type 188 * (member name -> type mapping). 189 */ 190 public Map<String, Class<?>> memberTypes() { 191 return memberTypes; 192 } 193 194 /** 195 * Returns members of this annotation type 196 * (member name -> associated Method object mapping). 197 */ 198 public Map<String, Method> members() { 199 return members; 200 } 201 202 /** 203 * Returns the default values for this annotation type 204 * (Member name -> default value mapping). 205 */ 206 public Map<String, Object> memberDefaults() { 207 return memberDefaults; 208 } 209 210 /** 211 * Returns the retention policy for this annotation type. 212 */ 213 public RetentionPolicy retention() { 214 return retention; 215 } 216 217 /** 218 * Returns true if this this annotation type is inherited. 219 */ 220 public boolean isInherited() { 221 return inherited; 222 } 223 224 /** 225 * For debugging. 226 */ 227 public String toString() { 228 return "Annotation Type:\n" + 229 " Member types: " + memberTypes + "\n" + 230 " Member defaults: " + memberDefaults + "\n" + 231 " Retention policy: " + retention + "\n" + 232 " Inherited: " + inherited; 233 } 234 }