sessioncommandgroup.java

OSGI这是一个中间件,与UPNP齐名,是用于移植到嵌入式平台之上

/*
 * Copyright (c) 2003, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.knopflerfish.bundle.console;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Reader;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;

import org.knopflerfish.service.console.CommandGroup;
import org.knopflerfish.service.console.Session;
import org.osgi.framework.BundleContext;
import org.osgi.framework.InvalidSyntaxException;
import org.osgi.framework.ServiceReference;
import org.osgi.service.log.LogService;

// ******************** SessionCommandGroup ********************
/**
 * * Interface for commands to be handled by the console. * *
 * 
 * @author Gatespace AB *
 * @version $Revision: 1.1.1.1 $
 */

public class SessionCommandGroup implements CommandGroup {

    final static String NAME = "session";

    final static String help_alias = "alias [<alias>] [<val>] ...  - Set or show aliases";

    final static String help_help = "help [<command group> | all] - Help about specific command group or all command groups";

    final static String help_echo = "echo [-n] ...                - Echo command arguments";

    final static String help_enter = "enter <command group>        - Enter command group mode";

    final static String help_leave = "leave                        - Leave command group mode";

    final static String help_prompt = "prompt <command prompt>      - Set command prompt";

    final static String help_quit = "quit                         - Exit this session";

    final static String help_save = "save [<file>]                - Save current aliases as a property file";

    final static String help_restore = "restore [<file>]             - Restore aliases from a property file or from default aliases";

    final static String help_source = "source <URL>                 - Source commands at URL";

    final static String help_unalias = "unalias <alias name>         - Remove an alias";

    private BundleContext bc;

    public SessionCommandGroup(BundleContext bc) {
        this.bc = bc;
    }

    /**
     * Utility method used for logging.
     * 
     * @param level
     *            log level
     * @param msg
     *            log message
     * @param t
     *            throwable
     */
    void log(int level, String msg, Throwable t) {
        ServiceReference srLog = bc
                .getServiceReference("org.osgi.service.log.LogService");
        if (srLog != null) {
            LogService sLog = (LogService) bc.getService(srLog);
            if (sLog != null) {
                sLog.log(level, msg, t);
            }
            bc.ungetService(srLog);
        }
    }

    /**
     * Returns the command group name.
     * 
     * @return command name.
     */
    public String getGroupName() {
        return NAME;
    }

    /**
     * Returns short command group help.
     * 
     * @return short command group help.
     */
    public String getShortHelp() {
        return "Session commands built into the console";
    }

    /**
     * Returns long command group help.
     * 
     * @return long command group help.
     */
    public String getLongHelp() {
        return "Available " + NAME + " commands:\n" + "  " + help_alias + "\n"
                + "  " + help_echo + "\n" + "  " + help_enter + "\n" + "  "
                + help_help + "\n" + "  " + help_leave + "\n" + "  "
                + help_prompt + "\n" + "  " + help_quit + "\n" + "  "
                + help_save + "\n" + "  " + help_restore + "\n" + "  "
                + help_source + "\n" + "  " + help_unalias + "\n";
    }

    /**
     * Executes the command.
     * 
     * @param args
     *            argument list passed to the command
     * @param out
     *            output device to print result
     * @param in
     *            input for command
     * @return params logical format parameters
     */
    public int execute(String[] args, Reader in, PrintWriter out,
            Session session) {
        SessionImpl si = (SessionImpl) session;
        String usage = null;
        if (args.length > 0) {
            //
            // Help
            //
            if ("help".startsWith(args[0])) {
                if (args.length == 1) {
                    if ("".equals(si.currentGroup)) {
                        return help(out, si);
                    }
                    return helpAbout(si.currentGroup, out, si);
                } else if (args.length == 2) {
                    if (args[1].equals("all")) {
                        return help(out, si);
                    }
                    return helpAbout(args[1], out, si);
                }
                usage = help_help;
                //
                // Alias
                //
            } else if ("alias".startsWith(args[0])) {
                if (si == null) {
                    out.println("Alias not available from runCommand method");
                    return 1;
                }
                if (args.length == 1) {
                    for (Enumeration e = si.aliases.keys(); e.hasMoreElements();) {
                        String a = (String) e.nextElement();
                        out.println(a + " = " + si.aliases.getString(a));
                    }
                } else if (args.length == 2) {
                    String a = si.aliases.getString(args[1]);
                    if (a != null) {
                        out.println(args[1] + " = " + a);
                    } else {
                        out.println("No alias for: " + args[1]);
                    }
                } else {
                    String[] na = new String[args.length - 2];
                    System.arraycopy(args, 2, na, 0, na.length);
                    si.aliases.put(args[1], na);
                }
                return 0;
                //
                // Enter
                //
            } else if ("enter".startsWith(args[0])) {
                if (args.length == 2) {
                    try {
                        ServiceReference ref = Command.matchCommandGroup(bc,
                                args[1]);
                        if (ref != null) {
                            si.currentGroup = (String) ref
                                    .getProperty("groupName");
                        } else {
                            si.currentGroup = NAME;
                        }
                        return 0;
                    } catch (IOException e) {
                        out.println(e.getMessage());
                        return 1;
                    }
                }