1 /* 2 * Copyright 2003-2006 Sun Microsystems, Inc. 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. Sun designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 22 * CA 95054 USA or visit www.sun.com if you need additional information or 23 * have any questions. 24 */ 25 26 package sun.reflect.annotation; 27 28 import java.lang.annotation.*; 29 import java.lang.reflect.*; 30 import java.util.*; 31 import java.security.AccessController; 32 import java.security.PrivilegedAction; 33 34 /** 35 * Represents an annotation type at run time. Used to type-check annotations 36 * and apply member defaults. 37 * 38 * @author Josh Bloch 39 * @since 1.5 40 */ 41 public class AnnotationType { 42 /** 43 * Member name -> type mapping. Note that primitive types 44 * are represented by the class objects for the corresponding wrapper 45 * types. This matches the return value that must be used for a 46 * dynamic proxy, allowing for a simple isInstance test. 47 */ 48 private final Map<String, Class> memberTypes = new HashMap<String,Class>(); 49 50 /** 51 * Member name -> default value mapping. 52 */ 53 private final Map<String, Object> memberDefaults = 54 new HashMap<String, Object>(); 55 56 /** 57 * Member name -> Method object mapping. This (and its assoicated 58 * accessor) are used only to generate AnnotationTypeMismatchExceptions. 59 */ 60 private final Map<String, Method> members = new HashMap<String, Method>(); 61 62 /** 63 * The retention policy for this annotation type. 64 */ 65 private RetentionPolicy retention = RetentionPolicy.RUNTIME;; 66 67 /** 68 * Whether this annotation type is inherited. 69 */ 70 private boolean inherited = false; 71 72 /** 73 * Returns an AnnotationType instance for the specified annotation type. 74 * 75 * @throw IllegalArgumentException if the specified class object for 76 * does not represent a valid annotation type 77 */ 78 public static synchronized AnnotationType getInstance( 79 Class annotationClass) 80 { 81 AnnotationType result = sun.misc.SharedSecrets.getJavaLangAccess(). 82 getAnnotationType(annotationClass); 83 if (result == null) 84 result = new AnnotationType((Class<?>) annotationClass); 85 86 return result; 87 } 88 89 /** 90 * Sole constructor. 91 * 92 * @param annotationClass the class object for the annotation type 93 * @throw IllegalArgumentException if the specified class object for 94 * does not represent a valid annotation type 95 */ 96 private AnnotationType(final Class<?> annotationClass) { 97 if (!annotationClass.isAnnotation()) 98 throw new IllegalArgumentException("Not an annotation type"); 99 100 Method[] methods = 101 AccessController.doPrivileged(new PrivilegedAction<Method[]>() { 102 public Method[] run() { 103 // Initialize memberTypes and defaultValues 104 return annotationClass.getDeclaredMethods(); 105 } 106 }); 107 108 109 for (Method method : methods) { 110 if (method.getParameterTypes().length != 0) 111 throw new IllegalArgumentException(method + " has params"); 112 String name = method.getName(); 113 Class type = method.getReturnType(); 114 memberTypes.put(name, invocationHandlerReturnType(type)); 115 members.put(name, method); 116 117 Object defaultValue = method.getDefaultValue(); 118 if (defaultValue != null) 119 memberDefaults.put(name, defaultValue); 120 121 members.put(name, method); 122 } 123 124 sun.misc.SharedSecrets.getJavaLangAccess(). 125 setAnnotationType(annotationClass, this); 126 127 // Initialize retention, & inherited fields. Special treatment 128 // of the corresponding annotation types breaks infinite recursion. 129 if (annotationClass != Retention.class && 130 annotationClass != Inherited.class) { 131 Retention ret = annotationClass.getAnnotation(Retention.class); 132 retention = (ret == null ? RetentionPolicy.CLASS : ret.value()); 133 inherited = annotationClass.isAnnotationPresent(Inherited.class); 134 } 135 } 136 137 /** 138 * Returns the type that must be returned by the invocation handler 139 * of a dynamic proxy in order to have the dynamic proxy return 140 * the specified type (which is assumed to be a legal member type 141 * for an annotation). 142 */ 143 public static Class invocationHandlerReturnType(Class type) { 144 // Translate primitives to wrappers 145 if (type == byte.class) 146 return Byte.class; 147 if (type == char.class) 148 return Character.class; 149 if (type == double.class) 150 return Double.class; 151 if (type == float.class) 152 return Float.class; 153 if (type == int.class) 154 return Integer.class; 155 if (type == long.class) 156 return Long.class; 157 if (type == short.class) 158 return Short.class; 159 if (type == boolean.class) 160 return Boolean.class; 161 162 // Otherwise, just return declared type 163 return type; 164 } 165 166 /** 167 * Returns member types for this annotation type 168 * (member name -> type mapping). 169 */ 170 public Map<String, Class> memberTypes() { 171 return memberTypes; 172 } 173 174 /** 175 * Returns members of this annotation type 176 * (member name -> associated Method object mapping). 177 */ 178 public Map<String, Method> members() { 179 return members; 180 } 181 182 /** 183 * Returns the default values for this annotation type 184 * (Member name -> default value mapping). 185 */ 186 public Map<String, Object> memberDefaults() { 187 return memberDefaults; 188 } 189 190 /** 191 * Returns the retention policy for this annotation type. 192 */ 193 public RetentionPolicy retention() { 194 return retention; 195 } 196 197 /** 198 * Returns true if this this annotation type is inherited. 199 */ 200 public boolean isInherited() { 201 return inherited; 202 } 203 204 /** 205 * For debugging. 206 */ 207 public String toString() { 208 StringBuffer s = new StringBuffer("Annotation Type:" + "\n"); 209 s.append(" Member types: " + memberTypes + "\n"); 210 s.append(" Member defaults: " + memberDefaults + "\n"); 211 s.append(" Retention policy: " + retention + "\n"); 212 s.append(" Inherited: " + inherited); 213 return s.toString(); 214 } 215 }