/*
 * 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;

/**
 * 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>
 * Base class with security related methods that work on JDK 1.1.
 */
class SecuritySupport {

    /*
     * Make this of type Object so that the verifier won't try to prove its type, thus possibly
     * trying to load the SecuritySupport12 class.
     */
    private static final Object securitySupport;

    static {
        SecuritySupport ss = null;
        try {
            Class c = Class.forName("java.security.AccessController");
            // if that worked, we're on 1.2.
         /*
          * // don't reference the class explicitly so it doesn't // get dragged in accidentally. c
          * = Class.forName("javax.mail.SecuritySupport12"); Constructor cons = c.getConstructor(new
          * Class[] { }); ss = (SecuritySupport)cons.newInstance(new Object[] { });
          */
         /*
          * Unfortunately, we can't load the class using reflection because the class is package
          * private. And the class has to be package private so the APIs aren't exposed to other
          * code that could use them to circumvent security. Thus, we accept the risk that the
          * direct reference might fail on some JDK 1.1 JVMs, even though we would never execute
          * this code in such a case. Sigh...
          */
            ss = new SecuritySupport12();
        } catch (Exception ex) {
            // ignore it
        } finally {
            if (ss == null)
                ss = new SecuritySupport();
            securitySupport = ss;
        }
    }

    /**
     * Return an appropriate instance of this class, depending on whether we're on a JDK 1.1 or J2SE
     * 1.2 (or later) system.
     */
    static SecuritySupport getInstance() {
        return (SecuritySupport) securitySupport;
    }

    ClassLoader getContextClassLoader() {
        return null;
    }

    boolean getFileExists(File f) {
        return f.exists();
    }

    FileInputStream getFileInputStream(File file) throws FileNotFoundException {
        return new FileInputStream(file);
    }

    long getLastModified(File f) {
        return f.lastModified();
    }

    ClassLoader getParentClassLoader(ClassLoader cl) {
        return null;
    }

    InputStream getResourceAsStream(ClassLoader cl, String name) {
        InputStream ris;
        if (cl == null) {
            ris = ClassLoader.getSystemResourceAsStream(name);
        } else {
            ris = cl.getResourceAsStream(name);
        }
        return ris;
    }

    ClassLoader getSystemClassLoader() {
        return null;
    }

    String getSystemProperty(String propName) {
        return System.getProperty(propName);
    }
}