/*

 * Copyright (c) 2004, 2008, 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.net;

import java.io.*;

import java.security.AccessController;

import java.security.PrivilegedAction;

import java.util.Properties;

/*

 * This class allows for centralized access to Networking properties.

 * Default values are loaded from the file jre/lib/net.properties

 *

 *

 * @author Jean-Christophe Collet

 *

 */

public class NetProperties {

    static private Properties props = new Properties();

    static {

        AccessController.doPrivileged(

            new PrivilegedAction<Void>() {

                public Void run() {

                    loadDefaultProperties();

                    return null;

                }});

    }

    private NetProperties() { };

    /*

     * Loads the default networking system properties

     * the file is in jre/lib/net.properties

     */

    static private void loadDefaultProperties() {

        String fname = System.getProperty("java.home");

        if (fname == null) {

            throw new Error("Can't find java.home ??");

        }

        try {

            File f = new File(fname, "lib");

            f = new File(f, "net.properties");

            fname = f.getCanonicalPath();

            InputStream in = new FileInputStream(fname);

            BufferedInputStream bin = new BufferedInputStream(in);

            props.load(bin);

            bin.close();

        } catch (Exception e) {

            // Do nothing. We couldn't find or access the file

            // so we won't have default properties...

        }

    }

    /**

     * Get a networking system property. If no system property was defined

     * returns the default value, if it exists, otherwise returns

     * <code>null</code>.

     * @param      key  the property name.

     * @throws  SecurityException  if a security manager exists and its

     *          <code>checkPropertiesAccess</code> method doesn't allow access

     *          to the system properties.

     * @return the <code>String</code> value for the property,

     *         or <code>null</code>

     */

    static public String get(String key) {

        String def = props.getProperty(key);

        try {

            return System.getProperty(key, def);

        } catch (IllegalArgumentException e) {

        } catch (NullPointerException e) {

        }

        return null;

    }

    /**

     * Get an Integer networking system property. If no system property was

     * defined returns the default value, if it exists, otherwise returns

     * <code>null</code>.

     * @param   key     the property name.

     * @param   defval  the default value to use if the property is not found

     * @throws  SecurityException  if a security manager exists and its

     *          <code>checkPropertiesAccess</code> method doesn't allow access

     *          to the system properties.

     * @return the <code>Integer</code> value for the property,

     *         or <code>null</code>

     */

    static public Integer getInteger(String key, int defval) {

        String val = null;

        try {

            val = System.getProperty(key, props.getProperty(key));

        } catch (IllegalArgumentException e) {

        } catch (NullPointerException e) {

        }

        if (val != null) {

            try {

                return Integer.decode(val);

            } catch (NumberFormatException ex) {

            }

        }

        return new Integer(defval);

    }

    /**

     * Get a Boolean networking system property. If no system property was

     * defined returns the default value, if it exists, otherwise returns

     * <code>null</code>.

     * @param   key     the property name.

     * @throws  SecurityException  if a security manager exists and its

     *          <code>checkPropertiesAccess</code> method doesn't allow access

     *          to the system properties.

     * @return the <code>Boolean</code> value for the property,

     *         or <code>null</code>

     */

    static public Boolean getBoolean(String key) {

        String val = null;

        try {

            val = System.getProperty(key, props.getProperty(key));

        } catch (IllegalArgumentException e) {

        } catch (NullPointerException e) {

        }

        if (val != null) {

            try {

                return Boolean.valueOf(val);

            } catch (NumberFormatException ex) {

            }

        }

        return null;

    }

}