Showing the changes to java/pkg/sun/reflect/Reflection.java (1 of 18352 files). Show all
Unified · Split
| @@ -0,0 +1,325 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (c) 2001, 2006, 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; | ||
| 27 | |||
| 28 | import java.lang.reflect.*; | ||
| 29 | import java.util.Collections; | ||
| 30 | import java.util.HashMap; | ||
| 31 | import java.util.Map; | ||
| 32 | |||
| 33 | /** Common utility routines used by both java.lang and | ||
| 34 | java.lang.reflect */ | ||
| 35 | |||
| 36 | public class Reflection { | ||
| 37 | |||
| 38 | /** Used to filter out fields and methods from certain classes from public | ||
| 39 | view, where they are sensitive or they may contain VM-internal objects. | ||
| 40 | These Maps are updated very rarely. Rather than synchronize on | ||
| 41 | each access, we use copy-on-write */ | ||
| 42 | private static volatile Map<Class,String[]> fieldFilterMap; | ||
| 43 | private static volatile Map<Class,String[]> methodFilterMap; | ||
| 44 | |||
| 45 | static { | ||
| 46 | Map<Class,String[]> map = new HashMap<Class,String[]>(); | ||
| 47 | map.put(Reflection.class, | ||
| 48 | new String[] {"fieldFilterMap", "methodFilterMap"}); | ||
| 49 | map.put(System.class, new String[] {"security"}); | ||
| 50 | fieldFilterMap = map; | ||
| 51 | |||
| 52 | methodFilterMap = new HashMap<Class,String[]>(); | ||
| 53 | } | ||
| 54 | |||
| 55 | /** Returns the class of the method <code>realFramesToSkip</code> | ||
| 56 | frames up the stack (zero-based), ignoring frames associated | ||
| 57 | with java.lang.reflect.Method.invoke() and its implementation. | ||
| 58 | The first frame is that associated with this method, so | ||
| 59 | <code>getCallerClass(0)</code> returns the Class object for | ||
| 60 | sun.reflect.Reflection. Frames associated with | ||
| 61 | java.lang.reflect.Method.invoke() and its implementation are | ||
| 62 | completely ignored and do not count toward the number of "real" | ||
| 63 | frames skipped. */ | ||
| 64 | public static native Class getCallerClass(int realFramesToSkip); | ||
| 65 | |||
| 66 | /** Retrieves the access flags written to the class file. For | ||
| 67 | inner classes these flags may differ from those returned by | ||
| 68 | Class.getModifiers(), which searches the InnerClasses | ||
| 69 | attribute to find the source-level access flags. This is used | ||
| 70 | instead of Class.getModifiers() for run-time access checks due | ||
| 71 | to compatibility reasons; see 4471811. Only the values of the | ||
| 72 | low 13 bits (i.e., a mask of 0x1FFF) are guaranteed to be | ||
| 73 | valid. */ | ||
| 74 | private static native int getClassAccessFlags(Class c); | ||
| 75 | |||
| 76 | /** A quick "fast-path" check to try to avoid getCallerClass() | ||
| 77 | calls. */ | ||
| 78 | public static boolean quickCheckMemberAccess(Class memberClass, | ||
| 79 | int modifiers) | ||
| 80 | { | ||
| 81 | return Modifier.isPublic(getClassAccessFlags(memberClass) & modifiers); | ||
| 82 | } | ||
| 83 | |||
| 84 | public static void ensureMemberAccess(Class currentClass, | ||
| 85 | Class memberClass, | ||
| 86 | Object target, | ||
| 87 | int modifiers) | ||
| 88 | throws IllegalAccessException | ||
| 89 | { | ||
| 90 | if (currentClass == null || memberClass == null) { | ||
| 91 | throw new InternalError(); | ||
| 92 | } | ||
| 93 | |||
| 94 | if (!verifyMemberAccess(currentClass, memberClass, target, modifiers)) { | ||
| 95 | throw new IllegalAccessException("Class " + currentClass.getName() + | ||
| 96 | " can not access a member of class " + | ||
| 97 | memberClass.getName() + | ||
| 98 | " with modifiers \"" + | ||
| 99 | Modifier.toString(modifiers) + | ||
| 100 | "\""); | ||
| 101 | } | ||
| 102 | } | ||
| 103 | |||
| 104 | public static boolean verifyMemberAccess(Class currentClass, | ||
| 105 | // Declaring class of field | ||
| 106 | // or method | ||
| 107 | Class memberClass, | ||
| 108 | // May be NULL in case of statics | ||
| 109 | Object target, | ||
| 110 | int modifiers) | ||
| 111 | { | ||
| 112 | // Verify that currentClass can access a field, method, or | ||
| 113 | // constructor of memberClass, where that member's access bits are | ||
| 114 | // "modifiers". | ||
| 115 | |||
| 116 | boolean gotIsSameClassPackage = false; | ||
| 117 | boolean isSameClassPackage = false; | ||
| 118 | |||
| 119 | if (currentClass == memberClass) { | ||
| 120 | // Always succeeds | ||
| 121 | return true; | ||
| 122 | } | ||
| 123 | |||
| 124 | if (!Modifier.isPublic(getClassAccessFlags(memberClass))) { | ||
| 125 | isSameClassPackage = isSameClassPackage(currentClass, memberClass); | ||
| 126 | gotIsSameClassPackage = true; | ||
| 127 | if (!isSameClassPackage) { | ||
| 128 | return false; | ||
| 129 | } | ||
| 130 | } | ||
| 131 | |||
| 132 | // At this point we know that currentClass can access memberClass. | ||
| 133 | |||
| 134 | if (Modifier.isPublic(modifiers)) { | ||
| 135 | return true; | ||
| 136 | } | ||
| 137 | |||
| 138 | boolean successSoFar = false; | ||
| 139 | |||
| 140 | if (Modifier.isProtected(modifiers)) { | ||
| 141 | // See if currentClass is a subclass of memberClass | ||
| 142 | if (isSubclassOf(currentClass, memberClass)) { | ||
| 143 | successSoFar = true; | ||
| 144 | } | ||
| 145 | } | ||
| 146 | |||
| 147 | if (!successSoFar && !Modifier.isPrivate(modifiers)) { | ||
| 148 | if (!gotIsSameClassPackage) { | ||
| 149 | isSameClassPackage = isSameClassPackage(currentClass, | ||
| 150 | memberClass); | ||
| 151 | gotIsSameClassPackage = true; | ||
| 152 | } | ||
| 153 | |||
| 154 | if (isSameClassPackage) { | ||
| 155 | successSoFar = true; | ||
| 156 | } | ||
| 157 | } | ||
| 158 | |||
| 159 | if (!successSoFar) { | ||
| 160 | return false; | ||
| 161 | } | ||
| 162 | |||
| 163 | if (Modifier.isProtected(modifiers)) { | ||
| 164 | // Additional test for protected members: JLS 6.6.2 | ||
| 165 | Class targetClass = (target == null ? memberClass : target.getClass()); | ||
| 166 | if (targetClass != currentClass) { | ||
| 167 | if (!gotIsSameClassPackage) { | ||
| 168 | isSameClassPackage = isSameClassPackage(currentClass, memberClass); | ||
| 169 | gotIsSameClassPackage = true; | ||
| 170 | } | ||
| 171 | if (!isSameClassPackage) { | ||
| 172 | if (!isSubclassOf(targetClass, currentClass)) { | ||
| 173 | return false; | ||
| 174 | } | ||
| 175 | } | ||
| 176 | } | ||
| 177 | } | ||
| 178 | |||
| 179 | return true; | ||
| 180 | } | ||
| 181 | |||
| 182 | private static boolean isSameClassPackage(Class c1, Class c2) { | ||
| 183 | return isSameClassPackage(c1.getClassLoader(), c1.getName(), | ||
| 184 | c2.getClassLoader(), c2.getName()); | ||
| 185 | } | ||
| 186 | |||
| 187 | /** Returns true if two classes are in the same package; classloader | ||
| 188 | and classname information is enough to determine a class's package */ | ||
| 189 | private static boolean isSameClassPackage(ClassLoader loader1, String name1, | ||
| 190 | ClassLoader loader2, String name2) | ||
| 191 | { | ||
| 192 | if (loader1 != loader2) { | ||
| 193 | return false; | ||
| 194 | } else { | ||
| 195 | int lastDot1 = name1.lastIndexOf('.'); | ||
| 196 | int lastDot2 = name2.lastIndexOf('.'); | ||
| 197 | if ((lastDot1 == -1) || (lastDot2 == -1)) { | ||
| 198 | // One of the two doesn't have a package. Only return true | ||
| 199 | // if the other one also doesn't have a package. | ||
| 200 | return (lastDot1 == lastDot2); | ||
| 201 | } else { | ||
| 202 | int idx1 = 0; | ||
| 203 | int idx2 = 0; | ||
| 204 | |||
| 205 | // Skip over '['s | ||
| 206 | if (name1.charAt(idx1) == '[') { | ||
| 207 | do { | ||
| 208 | idx1++; | ||
| 209 | } while (name1.charAt(idx1) == '['); | ||
| 210 | if (name1.charAt(idx1) != 'L') { | ||
| 211 | // Something is terribly wrong. Shouldn't be here. | ||
| 212 | throw new InternalError("Illegal class name " + name1); | ||
| 213 | } | ||
| 214 | } | ||
| 215 | if (name2.charAt(idx2) == '[') { | ||
| 216 | do { | ||
| 217 | idx2++; | ||
| 218 | } while (name2.charAt(idx2) == '['); | ||
| 219 | if (name2.charAt(idx2) != 'L') { | ||
| 220 | // Something is terribly wrong. Shouldn't be here. | ||
| 221 | throw new InternalError("Illegal class name " + name2); | ||
| 222 | } | ||
| 223 | } | ||
| 224 | |||
| 225 | // Check that package part is identical | ||
| 226 | int length1 = lastDot1 - idx1; | ||
| 227 | int length2 = lastDot2 - idx2; | ||
| 228 | |||
| 229 | if (length1 != length2) { | ||
| 230 | return false; | ||
| 231 | } | ||
| 232 | return name1.regionMatches(false, idx1, name2, idx2, length1); | ||
| 233 | } | ||
| 234 | } | ||
| 235 | } | ||
| 236 | |||
| 237 | static boolean isSubclassOf(Class queryClass, | ||
| 238 | Class ofClass) | ||
| 239 | { | ||
| 240 | while (queryClass != null) { | ||
| 241 | if (queryClass == ofClass) { | ||
| 242 | return true; | ||
| 243 | } | ||
| 244 | queryClass = queryClass.getSuperclass(); | ||
| 245 | } | ||
| 246 | return false; | ||
| 247 | } | ||
| 248 | |||
| 249 | // fieldNames must contain only interned Strings | ||
| 250 | public static synchronized void registerFieldsToFilter(Class containingClass, | ||
| 251 | String ... fieldNames) { | ||
| 252 | fieldFilterMap = | ||
| 253 | registerFilter(fieldFilterMap, containingClass, fieldNames); | ||
| 254 | } | ||
| 255 | |||
| 256 | // methodNames must contain only interned Strings | ||
| 257 | public static synchronized void registerMethodsToFilter(Class containingClass, | ||
| 258 | String ... methodNames) { | ||
| 259 | methodFilterMap = | ||
| 260 | registerFilter(methodFilterMap, containingClass, methodNames); | ||
| 261 | } | ||
| 262 | |||
| 263 | private static Map<Class,String[]> registerFilter(Map<Class,String[]> map, | ||
| 264 | Class containingClass, String ... names) { | ||
| 265 | if (map.get(containingClass) != null) { | ||
| 266 | throw new IllegalArgumentException | ||
| 267 | ("Filter already registered: " + containingClass); | ||
| 268 | } | ||
| 269 | map = new HashMap<Class,String[]>(map); | ||
| 270 | map.put(containingClass, names); | ||
| 271 | return map; | ||
| 272 | } | ||
| 273 | |||
| 274 | public static Field[] filterFields(Class containingClass, | ||
| 275 | Field[] fields) { | ||
| 276 | if (fieldFilterMap == null) { | ||
| 277 | // Bootstrapping | ||
| 278 | return fields; | ||
| 279 | } | ||
| 280 | return (Field[])filter(fields, fieldFilterMap.get(containingClass)); | ||
| 281 | } | ||
| 282 | |||
| 283 | public static Method[] filterMethods(Class containingClass, Method[] methods) { | ||
| 284 | if (methodFilterMap == null) { | ||
| 285 | // Bootstrapping | ||
| 286 | return methods; | ||
| 287 | } | ||
| 288 | return (Method[])filter(methods, methodFilterMap.get(containingClass)); | ||
| 289 | } | ||
| 290 | |||
| 291 | private static Member[] filter(Member[] members, String[] filteredNames) { | ||
| 292 | if ((filteredNames == null) || (members.length == 0)) { | ||
| 293 | return members; | ||
| 294 | } | ||
| 295 | int numNewMembers = 0; | ||
| 296 | for (Member member : members) { | ||
| 297 | boolean shouldSkip = false; | ||
| 298 | for (String filteredName : filteredNames) { | ||
| 299 | if (member.getName() == filteredName) { | ||
| 300 | shouldSkip = true; | ||
| 301 | break; | ||
| 302 | } | ||
| 303 | } | ||
| 304 | if (!shouldSkip) { | ||
| 305 | ++numNewMembers; | ||
| 306 | } | ||
| 307 | } | ||
| 308 | Member[] newMembers = | ||
| 309 | (Member[])Array.newInstance(members[0].getClass(), numNewMembers); | ||
| 310 | int destIdx = 0; | ||
| 311 | for (Member member : members) { | ||
| 312 | boolean shouldSkip = false; | ||
| 313 | for (String filteredName : filteredNames) { | ||
| 314 | if (member.getName() == filteredName) { | ||
| 315 | shouldSkip = true; | ||
| 316 | break; | ||
| 317 | } | ||
| 318 | } | ||
| 319 | if (!shouldSkip) { | ||
| 320 | newMembers[destIdx++] = member; | ||
| 321 | } | ||
| 322 | } | ||
| 323 | return newMembers; | ||
| 324 | } | ||
| 325 | } | ||