shellconsole.java

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/*
 *  Copyright (c) 2001 Sun Microsystems, Inc.  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *  notice, this list of conditions and the following disclaimer.
 *
 *  2. 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.
 *
 *  3. The end-user documentation included with the redistribution,
 *  if any, must include the following acknowledgment:
 *  "This product includes software developed by the
 *  Sun Microsystems, Inc. for Project JXTA."
 *  Alternately, this acknowledgment may appear in the software itself,
 *  if and wherever such third-party acknowledgments normally appear.
 *
 *  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
 *  not be used to endorse or promote products derived from this
 *  software without prior written permission. For written
 *  permission, please contact Project JXTA at http://www.jxta.org.
 *
 *  5. Products derived from this software may not be called "JXTA",
 *  nor may "JXTA" appear in their name, without prior written
 *  permission of Sun.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 SUN MICROSYSTEMS OR
 *  ITS 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.
 *  ====================================================================
 *
 *  This software consists of voluntary contributions made by many
 *  individuals on behalf of Project JXTA.  For more
 *  information on Project JXTA, please see
 *  <http://www.jxta.org/>.
 *
 *  This license is based on the BSD license adopted by the Apache Foundation.
 *
 *  $Id: ShellConsole.java,v 1.56 2006/06/14 16:37:11 bondolo Exp $
 */
package net.jxta.impl.shell;

import java.awt.HeadlessException;
import java.io.BufferedReader;
import java.io.InterruptedIOException;
import java.io.Writer;

import java.util.logging.Level;
import java.util.logging.Logger;

import net.jxta.peergroup.PeerGroup;

import net.jxta.impl.shell.ShellApp;

/**
 *  A container for JXTA Shell Application
 */
public abstract class ShellConsole {
    
    /**
     *  Log4J Logger
     **/
    private static final java.util.logging.Logger LOG = java.util.logging.Logger.getLogger(ShellConsole.class.getName());;
    
    // the name of the system property that will force the shell to
    // come up in terminal mode
    private final static String NOWINDOWPROPNAME = "SHELLNOWINDOW";
    
    /**
     *  The name of this console.
     **/
    private String consoleName = null;
    
    /**
     * The root application for this console. Exiting this application will
     * close the consoloe.
     */
    protected ShellApp  rootApp;

    /**
     *  Creates a new terminal window with rows row and cols columns to display.
     *
     *  @param  useName  the name of the console
     */
    public ShellConsole( ShellApp rootApp, String useName ) {
        this.rootApp = rootApp;
        consoleName = useName;
    }
    
    /**
     *  Gets the consoleName attribute of the ShellConsole object
     *
     * @return    The consoleName value
     **/
    public String getConsoleName() {
        return consoleName;
    }
    
    /**
     *  Clear the shell window.
     **/
    public abstract void clear();
    
    /**
     *  Terminates the current console.
     */
    public void destroy() {
        rootApp = null;
    }
    
    /**
     *  Read from the console.
     *
     * @return a line read from the console.
     * @throws InterruptedIOException when the reading thread is interrupted
     * before a line has been read.
     **/
    public abstract String read() throws InterruptedIOException;
    
    /**
     *  Write to the console.
     *
     * @param  msg  The message to write.
     **/
    public abstract void write(String msg);
    
    /**
     *  Sets the prompt to be used when reading input.
     **/
    public abstract void setPrompt( String prompt );
    
    /**
     *  Replaces the current command line with the command indicated
     *
     *  @param  cmd     the command replacing the typed command
     **/
    public abstract void setCommandLine( String cmd);
    
    /**
     *  Specify which group should be monitored for status.
     **/
    public abstract void setStatusGroup( PeerGroup group );
    
    /**
     *  Returns the application associated with this console.
     *
     *  @return the application associated with this console or <tt>null</tt> if 
     *  the console has been destroyed.
     */
    public ShellApp getShellApp() {
        return rootApp;
    }

    /**
     *  Returns the command this console sends if the cursor down key was
     *  pressed.
     *
     *@return    command this console send if the cursor down key was pressed
     **/
    public abstract String getCursorDownName();
    

    /**
     *  Returns the command this console sends if the cursor up key was pressed.
     *
     *@return    command this console send if the cursor up key was pressed
     **/
    public abstract String getCursorUpName();
    
    /**
     *  Creates a new ShellConsole instance.
     *
     *  @param useName the name of the console to be created.
     **/
    public final static ShellConsole newConsole( ShellApp rootApp, String useName ) {
        boolean tryWindow = !Boolean.getBoolean(NOWINDOWPROPNAME);
        
        try {
            return newConsole(rootApp, useName, tryWindow);
        }
        catch (HeadlessException noWindow) {
            if (LOG.isLoggable(java.util.logging.Level.WARNING)) {
                LOG.log(Level.WARNING,
                        "Could not open console window. Trying text console",
                        noWindow);
            }
            return newConsole(rootApp, useName, false);
        }
    }

    /**
     *  Creates a new ShellConsole instance.
     *
     *  @param useName the name of the console to be created.
     *  @param windowed if true then the console created will be a window.
     **/
    public final static ShellConsole newConsole( ShellApp rootApp, String useName, boolean windowed ) {
        if( windowed ) {
            return new SwingShellConsole( rootApp, useName, 30, 70 );
        } else {
            return new ConsoleShellConsole( rootApp, useName );
        }
    }
}