001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the "License");
007 * you may not use this file except in compliance with the License.
008 * You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 /*
019 * $Id: SecuritySupport.java 1225414 2011-12-29 02:38:30Z mrglavas $
020 */
021
022 package org.apache.xalan.extensions;
023
024 import java.io.File;
025 import java.io.FileInputStream;
026 import java.io.FileNotFoundException;
027 import java.io.InputStream;
028 import java.security.AccessController;
029 import java.security.PrivilegedAction;
030 import java.security.PrivilegedActionException;
031 import java.security.PrivilegedExceptionAction;
032
033 /**
034 * This class is duplicated for each Xalan-Java subpackage so keep it in sync.
035 * It is package private and therefore is not exposed as part of the Xalan-Java
036 * API.
037 *
038 * Security related methods that only work on J2SE 1.2 and newer.
039 */
040 final class SecuritySupport {
041
042 static ClassLoader getContextClassLoader() {
043 return (ClassLoader)
044 AccessController.doPrivileged(new PrivilegedAction() {
045 public Object run() {
046 ClassLoader cl = null;
047 try {
048 cl = Thread.currentThread().getContextClassLoader();
049 } catch (SecurityException ex) { }
050 return cl;
051 }
052 });
053 }
054
055 static ClassLoader getSystemClassLoader() {
056 return (ClassLoader)
057 AccessController.doPrivileged(new PrivilegedAction() {
058 public Object run() {
059 ClassLoader cl = null;
060 try {
061 cl = ClassLoader.getSystemClassLoader();
062 } catch (SecurityException ex) {}
063 return cl;
064 }
065 });
066 }
067
068 static ClassLoader getParentClassLoader(final ClassLoader cl) {
069 return (ClassLoader)
070 AccessController.doPrivileged(new PrivilegedAction() {
071 public Object run() {
072 ClassLoader parent = null;
073 try {
074 parent = cl.getParent();
075 } catch (SecurityException ex) {}
076
077 // eliminate loops in case of the boot
078 // ClassLoader returning itself as a parent
079 return (parent == cl) ? null : parent;
080 }
081 });
082 }
083
084 static String getSystemProperty(final String propName) {
085 return (String)
086 AccessController.doPrivileged(new PrivilegedAction() {
087 public Object run() {
088 return System.getProperty(propName);
089 }
090 });
091 }
092
093 static FileInputStream getFileInputStream(final File file)
094 throws FileNotFoundException
095 {
096 try {
097 return (FileInputStream)
098 AccessController.doPrivileged(new PrivilegedExceptionAction() {
099 public Object run() throws FileNotFoundException {
100 return new FileInputStream(file);
101 }
102 });
103 } catch (PrivilegedActionException e) {
104 throw (FileNotFoundException)e.getException();
105 }
106 }
107
108 static InputStream getResourceAsStream(final ClassLoader cl,
109 final String name)
110 {
111 return (InputStream)
112 AccessController.doPrivileged(new PrivilegedAction() {
113 public Object run() {
114 InputStream ris;
115 if (cl == null) {
116 ris = ClassLoader.getSystemResourceAsStream(name);
117 } else {
118 ris = cl.getResourceAsStream(name);
119 }
120 return ris;
121 }
122 });
123 }
124
125 static boolean getFileExists(final File f) {
126 return ((Boolean)
127 AccessController.doPrivileged(new PrivilegedAction() {
128 public Object run() {
129 return f.exists() ? Boolean.TRUE : Boolean.FALSE;
130 }
131 })).booleanValue();
132 }
133
134 static long getLastModified(final File f) {
135 return ((Long)
136 AccessController.doPrivileged(new PrivilegedAction() {
137 public Object run() {
138 return new Long(f.lastModified());
139 }
140 })).longValue();
141 }
142
143 private SecuritySupport () {}
144 }