CommandLine.java

/*
 * This file or a portion of this file is licensed under the terms of
 * the Globus Toolkit Public License, found in file GTPL, or at
 * http://www.globus.org/toolkit/download/license.html. This notice must
 * appear in redistributions of this file, with or without modification.
 *
 * Redistributions of this Software, with or without modification, must
 * reproduce the GTPL in: (1) the Software, or (2) the Documentation or
 * some other similar material which is provided with the Software (if
 * any).
 *
 * Copyright 1999-2004 University of Chicago and The University of
 * Southern California. All rights reserved.
 */
package edu.isi.pegasus.planner.invocation;

import java.util.*;
import java.io.Writer;
import java.io.IOException;

/**
 * This class maintains the application that was run, and the
 * arguments to the commandline that were actually passed on to
 * the application.
 *
 * @author Jens-S. Vöckler
 * @author Yong Zhao
 * @version $Revision$
 * @see Job
 */
public class CommandLine extends Invocation implements HasText
{
  /**
   * This is the executable that was run. 
   */
  private String m_executable;

  /**
   * This is the data contained between the tags. There may be
   * no data. 
   */
  private StringBuffer m_value;

  /**
   * Default c'tor: Construct a hollow shell and allow further
   * information to be added later.
   */
  public CommandLine()
  {
    m_executable = null;
    m_value = null;
  }

  /**
   * Constructs an applications without arguments.
   * @param executable is the name of the application.
   */
  public CommandLine( String executable )
  {
    m_executable = executable;
    m_value = null;
  }

  /**
   * Constructs an applications with arguments.
   * @param executable is the name of the application.
   * @param value represents the argument line passed.
   */
  public CommandLine( String executable, String value )
  {
    m_executable = executable;
    m_value = new StringBuffer(value);
  }

  /**
   * Appends a piece of text to the existing text. 
   * @param fragment is a piece of text to append to existing text.
   * Appending <code>null</code> is a noop.
   */
  public void appendValue( String fragment )
  {
    if ( fragment != null ) {
      if ( this.m_value == null ) this.m_value = new StringBuffer(fragment);
      else this.m_value.append( fragment );
    }
  }

  /**
   * Accessor
   *
   * @see #setExecutable(String)
   */
  public String getExecutable()
  { return this.m_executable; }

  /**
   * Accessor.
   *
   * @param executable
   * @see #getExecutable()
   */
  public void setExecutable( String executable )
  { this.m_executable = executable; }


  /**
   * Accessor
   *
   * @see #setValue(String)
   */
  public String getValue()
  { 
    return ( m_value == null ? null : m_value.toString() ); 
  }

  /**
   * Accessor.
   *
   * @param value is the new value to set.
   * @see #getValue()
   */
  public void setValue( String value )
  { 
    this.m_value = ( value == null ? null : new StringBuffer(value) ); 
  }

  /**
   * Converts the active state into something meant for human consumption.
   * The method will be called when recursively traversing the instance
   * tree. 
   *
   * @param stream is a stream opened and ready for writing. This can also
   * be a string stream for efficient output.
   */
  public void toString( Writer stream )
    throws IOException
  { 
    throw new IOException( "method not implemented, please contact vds-support@griphyn.org" );
  }

  /**
   * Dumps the state of the current element as XML output. This function
   * can return the necessary data more efficiently, thus overwriting
   * the inherited method.
   *
   * @param indent is a <code>String</code> of spaces used for pretty
   * printing. The initial amount of spaces should be an empty string.
   * The parameter is used internally for the recursive traversal.
   *
   * @return a String which contains the state of the current class and
   * its siblings using XML. Note that these strings might become large.
   */
  public String toXML( String indent )
  {
    StringBuffer result = new StringBuffer(32 + m_executable.length());

    result.append( "<command-line executable=\"" );
    result.append( quote(m_executable,true) );

    if ( m_value == null ) {
      // no content
      result.append( "\"/>" );
    } else {
      // yes, content
      result.append( "\">" );
      result.append( quote(getValue(),false) );
      result.append( "</command-line>" );
    }

    return result.toString();
  }

  /**
   * Dump the state of the current element as XML output. This function
   * traverses all sibling classes as necessary, and converts the data
   * into pretty-printed XML output. The stream interface should be able
   * to handle large output efficiently.
   *
   * @param stream is a stream opened and ready for writing. This can also
   * be a string stream for efficient output.
   * @param indent is a <code>String</code> of spaces used for pretty
   * printing. The initial amount of spaces should be an empty string.
   * The parameter is used internally for the recursive traversal.
   * If a <code>null</code> value is specified, no indentation nor
   * linefeeds will be generated. 
   * @param namespace is the XML schema namespace prefix. If neither
   * empty nor null, each element will be prefixed with this prefix,
   * and the root element will map the XML namespace. 
   * @exception IOException if something fishy happens to the stream.
   */
  public void toXML( Writer stream, String indent, String namespace )
    throws IOException
  {
    String tag = ( namespace != null && namespace.length() > 0 ) ?
      namespace + ":command-line" : "command-line";

    // open tag
    if ( indent != null && indent.length() > 0 ) stream.write( indent );
    stream.write( '<' );
    stream.write( tag );
    writeAttribute( stream, " executable=\"", m_executable );

    if ( m_value != null ) {
      // yes, content
      stream.write( '>' );
      stream.write( quote(getValue(),false) );
      stream.write( "</" );
      stream.write( tag );
      stream.write( '>' );
    } else {
      // no content
      stream.write( "/>" );
    }
    if ( indent != null ) 
      stream.write( System.getProperty( "line.separator", "\r\n" ) );
  }
}