uninstjar.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: uninstjar.java,v 1.7 2004/05/20 00:16:50 bondolo Exp $
 */


package net.jxta.impl.shell.bin.uninstjar;

import net.jxta.impl.shell.*;

import java.io.*;
import java.util.*;
import java.net.*;

import net.jxta.pipe.*;
import net.jxta.peergroup.*;
import net.jxta.peer.*;
import net.jxta.document.*;
import net.jxta.id.*;


/**
 * 'uninstjar' Shell command to remove installed commands contained in the jar-file to be uninstalled.
 */
public class uninstjar extends ShellApp {
	protected List instJarList;
	protected ShellCmds cmds;
	
    public int startApp (String[] args) {
		if (args.length == 0) {
		    return syntaxError();
		}

        cmds = new ShellCmds(getEnv());
		
		// Construct a list containing all installed files (if any)
        instJarList = new ArrayList( Arrays.asList(cmds.getInstJars()) );

		// Check whether the environment variable contains files
		if (instJarList.isEmpty()) {
			return noJarsInstalledError();
		}
		
		// Check if we must uninstall all files
		if (args[0].equals("-all")) {
			List toRemoveList = new ArrayList( instJarList );
			uninstallJars(toRemoveList);
		} else {
	        // Construct list containing all File objects to be removed.
	        Vector toRemoveList = new Vector();
	        for (int i = 0, max = instJarList.size() - 1; i < args.length; i++) {
	        	// Check for index parameter.
	        	if (args[i].equals("-i")) {
		        	// Test whether the neccessary index argument exists.
			        if (++i >= args.length) {
			        	println("Error: Missing index argument!");
			        	break;
				    }
				    // Add file with parsed index argument to toRemoveList.
				    try {
				        int index = Integer.parseInt(args[i]);
				        if (index < 0 || index > max) {
					    	println("Error: '" + index + "' out of range [0.." + max + "]!");
						    continue;
						}
				        toRemoveList.addElement(instJarList.get(index));
				    } catch (NumberFormatException e) {
						println("Error: '" + args[i] + "' is not a valid number!");
				    }
				} else
				// Check for file parameter.
				if (args[i].equals("-f")) {
		        	// Test whether the neccessary file argument exists.
			        if (++i >= args.length) {
			        	println("Error: Missing file argument!");
			        	break;
				    }
					// Add corresponding File object to toRemoveList.
					File file = new File(args[i]);
		        	if (instJarList.contains(file)) {
			        	toRemoveList.addElement(file);
				    } else {
				    	println("Error: '" + file + "' not found!");
					}
				} else {
					println("Error: Unknown parameter '" + args[i] + "'!");
				}
	        }
	        // Remove all files contained in toRemoveList.
	        uninstallJars(toRemoveList);
	    }

        // Set the new value of environment variable INST_JARS.
        cmds.setInstJars(instJarList);
        
        return ShellApp.appNoError;
	}

    private int syntaxError () {
	    println ("Usage: uninstjar <-all | -f jar-file | -i index> [<-f jar-file | -i index> [...]]");
	    return ShellApp.appParamError;
    }

	private int noJarsInstalledError() {
		println("Error: No jar-files installed!");
		return ShellApp.appMiscError;
	}
	
	/**
	 * Removes a file from the list of installed jars.
	 *
	 * @param	file	the file to be uninstalled.
	 */
	protected void uninstallJar(File file) {
		instJarList.remove(file);
	}
	
	/**
	 * Uninstalls a given list of File objects from the list of installed jar-files.
	 *
	 * @param	list	URLs to be removed.
	 */
	protected void uninstallJars(List list) {
		for (Iterator e = list.iterator(); e.hasNext();) {
			uninstallJar((File)e.next());
		}
	}
	
	/**
	 * Returns a short description for this command (used by the Shell command 'man').
	 */
	public String getDescription() {
		return "Uninstalls jar-files previously installed with 'instjar'";
	}
	
	/**
	 * Prints the help text.
	 */
    public void help() {
      println("NAME");
      println("     uninstjar - uninstalls one or more jar-files previously");
      println("     installed with the command 'instjar'.");
      println(" "); 
      println("SYNOPSIS");
      println("     uninstjar <-all | -f file | -i index> [<-f file | -i index> [...]]");
      println(" ");
      println("DESCRIPTION");
      println(" ");
      println("This command uninstalls previously installed jar-files containing");
      println("additional Shell commands. Once uninstalled, the commands placed");
      println("in that jar-file are no longer available to the Shell.");
      println("An arbirtary number of jar-files to uninstall can be supplied.");
      println("Either through supplying the path to the jar-file itself or through");
      println("their indices, which can be obtained through invoking 'instjars'");
      println("with no arguments. The list of installed urls is stored in the environment");
      println("variable '" + ShellCmds.INST_JARS + "'.");
      println("So uninstalling means removing the corresponding entry from this");
      println("environment variable.");
      println(" ");
      println("EXAMPLE");
      println(" ");
      println("To uninstall a jar-file by supplying the path:");
      println("    JXTA>uninstjar -f c:/userlib/usrcmds.jar");
      println(" ");
      println("To uninstall a jar-file by its index first list all installed");
      println("jar-files with 'instjar':");
      println("    JXTA> instjar");
      println("    0 c:/userlib/usrcmds.jar");
      println("    1 c:/userlib/toolcmds.jar");
      println("Now uninstall a jar-file with its index:");
      println("    JXTA>uninstjar -i 1");
      println(" ");
      println("To uninstall all jar-files:");
      println("    JXTA>uninstjar -all");
      println(" ");
      println("SEE ALSO");
      println("    instjar ");
    }
}