SecuritySupport12.java

/*
 * Copyright 2002-2008 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.googlecode.html;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;

/**
 * This class is duplicated for each JAXP subpackage so keep it in sync. It is package private and
 * therefore is not exposed as part of the JAXP API.
 * <p>
 * Security related methods that only work on J2SE 1.2 and newer.
 */
class SecuritySupport12 extends SecuritySupport {

    ClassLoader getContextClassLoader() {
        return (ClassLoader) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                ClassLoader cl = null;
                try {
                    cl = Thread.currentThread().getContextClassLoader();
                } catch (SecurityException ex) {
                }
                return cl;
            }
        });
    }

    boolean getFileExists(final File f) {
        return ((Boolean) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                return new Boolean(f.exists());
            }
        })).booleanValue();
    }

    FileInputStream getFileInputStream(final File file) throws FileNotFoundException {
        try {
            return (FileInputStream) AccessController.doPrivileged(new PrivilegedExceptionAction() {
                public Object run() throws FileNotFoundException {
                    return new FileInputStream(file);
                }
            });
        } catch (PrivilegedActionException e) {
            throw (FileNotFoundException) e.getException();
        }
    }

    long getLastModified(final File f) {
        return ((Long) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                return new Long(f.lastModified());
            }
        })).longValue();
    }

    ClassLoader getParentClassLoader(final ClassLoader cl) {
        return (ClassLoader) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                ClassLoader parent = null;
                try {
                    parent = cl.getParent();
                } catch (SecurityException ex) {
                }

                // eliminate loops in case of the boot
                // ClassLoader returning itself as a parent
                return (parent == cl) ? null : parent;
            }
        });
    }

    InputStream getResourceAsStream(final ClassLoader cl, final String name) {
        return (InputStream) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                InputStream ris;
                if (cl == null) {
                    ris = ClassLoader.getSystemResourceAsStream(name);
                } else {
                    ris = cl.getResourceAsStream(name);
                }
                return ris;
            }
        });
    }

    ClassLoader getSystemClassLoader() {
        return (ClassLoader) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                ClassLoader cl = null;
                try {
                    cl = ClassLoader.getSystemClassLoader();
                } catch (SecurityException ex) {
                }
                return cl;
            }
        });
    }

    String getSystemProperty(final String propName) {
        return (String) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                return System.getProperty(propName);
            }
        });
    }

}