diff -r 836adbf7a2cd -r 3317bb8137f4 jdk/src/java.base/share/classes/sun/reflect/Reflection.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/java.base/share/classes/sun/reflect/Reflection.java Sun Aug 17 15:54:13 2014 +0100 @@ -0,0 +1,350 @@ +/* + * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +package sun.reflect; + +import java.lang.reflect.*; +import java.util.HashMap; +import java.util.Map; + +/** Common utility routines used by both java.lang and + java.lang.reflect */ + +public class Reflection { + + /** Used to filter out fields and methods from certain classes from public + view, where they are sensitive or they may contain VM-internal objects. + These Maps are updated very rarely. Rather than synchronize on + each access, we use copy-on-write */ + private static volatile Map,String[]> fieldFilterMap; + private static volatile Map,String[]> methodFilterMap; + + static { + Map,String[]> map = new HashMap,String[]>(); + map.put(Reflection.class, + new String[] {"fieldFilterMap", "methodFilterMap"}); + map.put(System.class, new String[] {"security"}); + fieldFilterMap = map; + + methodFilterMap = new HashMap<>(); + } + + /** Returns the class of the caller of the method calling this method, + ignoring frames associated with java.lang.reflect.Method.invoke() + and its implementation. */ + @CallerSensitive + public static native Class getCallerClass(); + + /** + * @deprecated This method will be removed in JDK 9. + * This method is a private JDK API and retained temporarily for + * existing code to run until a replacement API is defined. + */ + @Deprecated + public static native Class getCallerClass(int depth); + + /** Retrieves the access flags written to the class file. For + inner classes these flags may differ from those returned by + Class.getModifiers(), which searches the InnerClasses + attribute to find the source-level access flags. This is used + instead of Class.getModifiers() for run-time access checks due + to compatibility reasons; see 4471811. Only the values of the + low 13 bits (i.e., a mask of 0x1FFF) are guaranteed to be + valid. */ + public static native int getClassAccessFlags(Class c); + + /** A quick "fast-path" check to try to avoid getCallerClass() + calls. */ + public static boolean quickCheckMemberAccess(Class memberClass, + int modifiers) + { + return Modifier.isPublic(getClassAccessFlags(memberClass) & modifiers); + } + + public static void ensureMemberAccess(Class currentClass, + Class memberClass, + Object target, + int modifiers) + throws IllegalAccessException + { + if (currentClass == null || memberClass == null) { + throw new InternalError(); + } + + if (!verifyMemberAccess(currentClass, memberClass, target, modifiers)) { + throw new IllegalAccessException("Class " + currentClass.getName() + + " can not access a member of class " + + memberClass.getName() + + " with modifiers \"" + + Modifier.toString(modifiers) + + "\""); + } + } + + public static boolean verifyMemberAccess(Class currentClass, + // Declaring class of field + // or method + Class memberClass, + // May be NULL in case of statics + Object target, + int modifiers) + { + // Verify that currentClass can access a field, method, or + // constructor of memberClass, where that member's access bits are + // "modifiers". + + boolean gotIsSameClassPackage = false; + boolean isSameClassPackage = false; + + if (currentClass == memberClass) { + // Always succeeds + return true; + } + + if (!Modifier.isPublic(getClassAccessFlags(memberClass))) { + isSameClassPackage = isSameClassPackage(currentClass, memberClass); + gotIsSameClassPackage = true; + if (!isSameClassPackage) { + return false; + } + } + + // At this point we know that currentClass can access memberClass. + + if (Modifier.isPublic(modifiers)) { + return true; + } + + boolean successSoFar = false; + + if (Modifier.isProtected(modifiers)) { + // See if currentClass is a subclass of memberClass + if (isSubclassOf(currentClass, memberClass)) { + successSoFar = true; + } + } + + if (!successSoFar && !Modifier.isPrivate(modifiers)) { + if (!gotIsSameClassPackage) { + isSameClassPackage = isSameClassPackage(currentClass, + memberClass); + gotIsSameClassPackage = true; + } + + if (isSameClassPackage) { + successSoFar = true; + } + } + + if (!successSoFar) { + return false; + } + + if (Modifier.isProtected(modifiers)) { + // Additional test for protected members: JLS 6.6.2 + Class targetClass = (target == null ? memberClass : target.getClass()); + if (targetClass != currentClass) { + if (!gotIsSameClassPackage) { + isSameClassPackage = isSameClassPackage(currentClass, memberClass); + gotIsSameClassPackage = true; + } + if (!isSameClassPackage) { + if (!isSubclassOf(targetClass, currentClass)) { + return false; + } + } + } + } + + return true; + } + + private static boolean isSameClassPackage(Class c1, Class c2) { + return isSameClassPackage(c1.getClassLoader(), c1.getName(), + c2.getClassLoader(), c2.getName()); + } + + /** Returns true if two classes are in the same package; classloader + and classname information is enough to determine a class's package */ + private static boolean isSameClassPackage(ClassLoader loader1, String name1, + ClassLoader loader2, String name2) + { + if (loader1 != loader2) { + return false; + } else { + int lastDot1 = name1.lastIndexOf('.'); + int lastDot2 = name2.lastIndexOf('.'); + if ((lastDot1 == -1) || (lastDot2 == -1)) { + // One of the two doesn't have a package. Only return true + // if the other one also doesn't have a package. + return (lastDot1 == lastDot2); + } else { + int idx1 = 0; + int idx2 = 0; + + // Skip over '['s + if (name1.charAt(idx1) == '[') { + do { + idx1++; + } while (name1.charAt(idx1) == '['); + if (name1.charAt(idx1) != 'L') { + // Something is terribly wrong. Shouldn't be here. + throw new InternalError("Illegal class name " + name1); + } + } + if (name2.charAt(idx2) == '[') { + do { + idx2++; + } while (name2.charAt(idx2) == '['); + if (name2.charAt(idx2) != 'L') { + // Something is terribly wrong. Shouldn't be here. + throw new InternalError("Illegal class name " + name2); + } + } + + // Check that package part is identical + int length1 = lastDot1 - idx1; + int length2 = lastDot2 - idx2; + + if (length1 != length2) { + return false; + } + return name1.regionMatches(false, idx1, name2, idx2, length1); + } + } + } + + static boolean isSubclassOf(Class queryClass, + Class ofClass) + { + while (queryClass != null) { + if (queryClass == ofClass) { + return true; + } + queryClass = queryClass.getSuperclass(); + } + return false; + } + + // fieldNames must contain only interned Strings + public static synchronized void registerFieldsToFilter(Class containingClass, + String ... fieldNames) { + fieldFilterMap = + registerFilter(fieldFilterMap, containingClass, fieldNames); + } + + // methodNames must contain only interned Strings + public static synchronized void registerMethodsToFilter(Class containingClass, + String ... methodNames) { + methodFilterMap = + registerFilter(methodFilterMap, containingClass, methodNames); + } + + private static Map,String[]> registerFilter(Map,String[]> map, + Class containingClass, String ... names) { + if (map.get(containingClass) != null) { + throw new IllegalArgumentException + ("Filter already registered: " + containingClass); + } + map = new HashMap,String[]>(map); + map.put(containingClass, names); + return map; + } + + public static Field[] filterFields(Class containingClass, + Field[] fields) { + if (fieldFilterMap == null) { + // Bootstrapping + return fields; + } + return (Field[])filter(fields, fieldFilterMap.get(containingClass)); + } + + public static Method[] filterMethods(Class containingClass, Method[] methods) { + if (methodFilterMap == null) { + // Bootstrapping + return methods; + } + return (Method[])filter(methods, methodFilterMap.get(containingClass)); + } + + private static Member[] filter(Member[] members, String[] filteredNames) { + if ((filteredNames == null) || (members.length == 0)) { + return members; + } + int numNewMembers = 0; + for (Member member : members) { + boolean shouldSkip = false; + for (String filteredName : filteredNames) { + if (member.getName() == filteredName) { + shouldSkip = true; + break; + } + } + if (!shouldSkip) { + ++numNewMembers; + } + } + Member[] newMembers = + (Member[])Array.newInstance(members[0].getClass(), numNewMembers); + int destIdx = 0; + for (Member member : members) { + boolean shouldSkip = false; + for (String filteredName : filteredNames) { + if (member.getName() == filteredName) { + shouldSkip = true; + break; + } + } + if (!shouldSkip) { + newMembers[destIdx++] = member; + } + } + return newMembers; + } + + /** + * Tests if the given method is caller-sensitive and the declaring class + * is defined by either the bootstrap class loader or extension class loader. + */ + public static boolean isCallerSensitive(Method m) { + final ClassLoader loader = m.getDeclaringClass().getClassLoader(); + if (sun.misc.VM.isSystemDomainLoader(loader) || isExtClassLoader(loader)) { + return m.isAnnotationPresent(CallerSensitive.class); + } + return false; + } + + private static boolean isExtClassLoader(ClassLoader loader) { + ClassLoader cl = ClassLoader.getSystemClassLoader(); + while (cl != null) { + if (cl.getParent() == null && cl == loader) { + return true; + } + cl = cl.getParent(); + } + return false; + } +}