mkpipe.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: mkpipe.java,v 1.15 2003/11/24 21:29:20 tra Exp $
 */

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

import net.jxta.impl.shell.*;

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

import net.jxta.peer.*;
import net.jxta.peergroup.*;
import net.jxta.pipe.*;
import net.jxta.protocol.*;

/**
 * create an input or output pipe from a pipe advertisement
 */

public class mkpipe extends ShellApp {
    ShellEnv env;

    public mkpipe() {
    }

    public void stopApp () {
    }

    private int syntaxError () {

	println ("usage: mkpipe -i|o pipeAdv");
	return ShellApp.appParamError;
    }

    public int startApp (String[] args) {

      // check for the proper number of arguements and make sure they are valid
      if ((args == null) || (args.length != 2)) {
        return syntaxError();
      } else if ((args[0].equals ("-i") == false) &&
		 (args[0].equals ("-o") == false)) {
	return syntaxError();
      }

      env = getEnv();

      ShellObject obj = env.get (args[1]);
      if (obj == null) {
        println ("cat: cannot access " + args[1]);
        return ShellApp.appMiscError;
      }

      PipeAdvertisement adv = null;
      try {
        adv = (PipeAdvertisement) obj.getObject();
      } catch (Exception e) {
        // This is not an Advertisement
        println ("mkpipe: " + args[1] + " is not an PipeAdvertisement");
        return ShellApp.appMiscError;
      }

      if (adv == null) {
        println ("mkpipe: " + args[1] + " is empty");
        return ShellApp.appMiscError;
      }


      // InputPipe or OutputPipe ?
      if (args[0].equals ("-i")) {
	  InputPipe ip = null;
	  try {
	      ip = getGroup().getPipeService().createInputPipe (adv);
	  } catch (IOException e) {
	      println("mkpipe: cannot create an InputPipe onto " + args[1]);
	      return ShellApp.appMiscError;
	  }

          ShellObject old =
               env.add (getReturnVariable(),
			new ShellObject ("InputPipe of " + args[1], ip));
      } else {
	  OutputPipe op = null;
	  try {
              op = getGroup().getPipeService().createOutputPipe (adv,-1);
	  } catch (IOException e) {
	      println("mkpipe: cannot create an OutputPipe onto " + args[1]);
	      return ShellApp.appMiscError;
	  }
          ShellObject old =
               env.add (getReturnVariable(),
                        new ShellObject ("OutputPipe of " + args[1], op));
      }
      return ShellApp.appNoError;
    }

   public String getDescription() {
      return "Create a pipe";
   }

   public void help() {
      println("NAME");
      println("     mkpipe - create a pipe");
      println(" ");
      println("SYNOPSIS");
      println("     mkpipe -i|o <pipe advertisement>");
      println(" ");
      println("DESCRIPTION");
      println(" ");
      println("'mkpipe' creates an input pipe or an output pipe from a given");
      println("pipe advertisement document. In order for pipes to communicate");
      println("an input and output pipe needs to be created with the same");
      println("pipe advertisement. PipeServiceService advertisements are structured documents that");
      println("contains at least the unique pipe Id. The pipe Id uniquely");
      println("identifies a pipe in the JXTA world. Pipes are not localized");
      println("or binded to a physical peer. PipeServiceService connections are established");
      println("by searching for pipe advertisements and resolving dynamically");
      println("the location of an input pipe object binded to that advertisement.");
      println("An input pipe can be binded to the same pipe advertisement on");
      println("multiple peers transparently to the output pipe. The output pipe");
      println("does not need to known on which physical peer the input pipe is");
      println("located. To communicate with the pipe, the output pipe needs");
      println("to search for the input pipe that binds that advertisement.");
      println(" ");
      println("OPTIONS");
      println(" ");
      println("  -i create an input pipe");
      println("  -o create an output pipe");
      println(" ");
      println("EXAMPLE");
      println(" ");
      println("    JXTA> pipeadv = newpipe -n mypipe");
      println("    JXTA> inpipe = mkpipe -i pipeadv");
      println("    JXTA> msg = recv inpipe");
      println("    JXTA> data = get msg mytag");
      println(" ");
      println("This example creates a pipe advertisement 'pipeadv'");
      println("create an input pipe 'inpipe' and receive a message 'msg'");
      println("The body of the message associated with the tag 'mytag' is");
      println("retreived from the message via the 'get' command.");
      println(" ");
      println("SEE ALSO");
      println("    mkmsg put get send recv mkadv");
  }

}