Argument.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 org.griphyn.vdl.classes;

import org.griphyn.vdl.classes.*;
import java.util.*;
import java.io.IOException;
import java.io.Writer;
import java.io.Serializable;

/**
 * A class to encapsulate a command line argument line. The command line
 * is separated into a list of distinct fragments. Each fragment can only
 * be of type <code>Use</code> or <code>Text</code>.
 *
 * @author Jens-S. Vöckler
 * @author Yong Zhao
 * @version $Revision$
 * 
 * @see Leaf
 * @see Text
 * @see Use
 */
public class Argument extends VDL implements Serializable
{
  /**
   * Throws this message, if neither <text> nor <use>
   * elements are tried to be added.
   */
  private static final String c_error_message =
    "Only \"text\" and \"use\" elements are allowed inside an \"argument\".";

  /**
   * The command line consists of an ordered list of <code>Leaf</code>
   * pieces, which in their sum create the commandline. Any value passed
   * down is an arbitrary mix of the three potential <code>Leaf</code>
   * types. Each element only allows for <code>Text</code> and
   * <code>Use</code> children in arbitrary number and order.
   *
   * @see Leaf
   * @see Text
   * @see Use
   */
  private ArrayList m_leafList;

  /**
   * Each <code>Argument</code> is a fragment of the complete command
   * line. Each such group (of fragments) can be given a name. Special
   * names of the stdio handles refer to these handles.
   */
  private String m_name;

  /**
   * Array ctor.
   */
  public Argument()
  {
    this.m_leafList = new ArrayList();
  }

  /**
   * Standard ctor: Constructs a named <code>Argument</code> group.
   *
   * @param name is the identifier for the argument group.
   */
  public Argument( String name )
  {
    this.m_name = name;
    this.m_leafList = new ArrayList();
  }

  /**
   * Convenience ctor: Constructs a name argument group, and enters the
   * first (and possibly only) fragment into the group.
   *
   * @param name is the unique identifier for the argument group.
   * @param firstChild is the element to place into the argument group. Only
   * <code>Leaf</code>s of type <code>Use</code> or <code>Text</code>
   * are permissable.
   *
   * @see Leaf
   * @see Use
   * @see Text
   */
  public Argument( String name, Leaf firstChild )
  {
    this.m_name = name;
    this.m_leafList = new ArrayList();
    this.m_leafList.add(firstChild);
  }
  
  /**
   * Accessor: Appends a commandline fragment to the current group.
   *
   * @param vLeaf is the fragment to add. Note that only leaf values of
   * <code>Use</code> or <code>Text</code> are allowed.
   * @throws IndexOutOfBoundsException if the value cannot be added.
   * @throws IllegalArgumentException if the value type is neither
   *         <code>Use</code> nor <code>Text</code>.
   * @see Leaf
   * @see Text
   * @see Use
   */
  public void addLeaf( Leaf vLeaf )
    throws IndexOutOfBoundsException, IllegalArgumentException
  { 
    if ( vLeaf instanceof Text || vLeaf instanceof Use )
      this.m_leafList.add(vLeaf); 
    else
      throw new java.lang.IllegalArgumentException( c_error_message );
  }
  
  /**
   * Accessor: Inserts a <code>Leaf</code> value into a specific position
   * of this commandline group.
   *
   * @param index is the position to insert the item into
   * @param vLeaf is the value to append to the list. Note that only leaf
   *              values of <code>Use</code> or <code>Text</code> are allowed.
   * @throws IndexOutOfBoundsException if the value cannot be added.
   * @throws IllegalArgumentException if the value type is neither
   *         <code>Use</code> nor <code>Text</code>.
   *
   * @see Text
   * @see Use
   */
  public void addLeaf( int index, Leaf vLeaf )
    throws IndexOutOfBoundsException, IllegalArgumentException
  { 
    if ( vLeaf instanceof Text || vLeaf instanceof Use ) 
      this.m_leafList.add(index, vLeaf); 
    else
      throw new java.lang.IllegalArgumentException( c_error_message );
  }

  /**
   * Accessor: Enumerates the internal values that constitute the content
   * this commandline group.
   *
   * @return the iterator to the commandline group internal list.
   * @deprecated Use the new Collection based interfaces
   */
  public Enumeration enumerateLeaf()
  { 
    return Collections.enumeration(this.m_leafList); 
  }
  
  /**
   * Accessor: Obtains the <code>Leaf</code> at a certain position in the
   * commandline argument group.
   * 
   * @param index is the position in the list to obtain a value from
   * @return The <code>Use</code> or <code>Text</code> at the position.
   * @throws IndexOutOfBoundsException if the index points to an element
   *         in the list that does not contain any elments.
   *
   * @see Use
   * @see Text
   */
  public Leaf getLeaf(int index)
    throws IndexOutOfBoundsException
  {
    //-- check bound for index
    if ((index < 0) || (index >= this.m_leafList.size())) 
      throw new IndexOutOfBoundsException();

    return (Leaf) this.m_leafList.get(index);
  }

  /**
   * Accessor: Gets an array of all values that constitute the current
   * value content of this commandline group. This array is a copy to
   * avoid write-through modifications.
   *
   * @return an array with a mixture of either <code>Text</code> or
   *         <code>Use</code> values.
   *
   * @see Use
   * @see Text 
   * @deprecated Use the new Collection based interfaces
   */
  public Leaf[] getLeaf()
  {
    int size = this.m_leafList.size();
    Leaf[] mLeaf = new Leaf[size];
    System.arraycopy( this.m_leafList.toArray(new Leaf[0]), 0,
		      mLeaf, 0, size );
    return mLeaf;
  }

  /**
   * Accessor: Obtains the size of the commandline group. 
   *
   * @return number of elements that an external array needs to be sized to.
   */
  public int getLeafCount()
  {
    return this.m_leafList.size(); 
  }

  /**
   * Accessor: Gets an array of all values that constitute the current
   * content. This list is read-only. 
   *
   * @return an array with a mixture of either <code>Text</code> or
   *         <code>LFN</code> values.
   *
   * @see LFN
   * @see Text
   */
  public java.util.List getLeafList()
  {
    return Collections.unmodifiableList(this.m_leafList);
  }

  /**
   * Accessor: Obtains the current name of this commandline group.
   *
   * @return the name of this commandline group.
   * @see #setName(java.lang.String)
   */
  public String getName()
  {
    return this.m_name; 
  }

  /**
   * Accessor: Enumerates the internal values that constitute the content
   * of the <code>Scalar</code> element.
   *
   * @return an iterator to walk the list with.
   */
  public Iterator iterateLeaf()
  { 
    return this.m_leafList.iterator(); 
  }

  /**
   * Accessor: Enumerates the internal values that constitute the content
   * of the <code>Scalar</code> element.
   *
   * @return an enumeration to walk the list with.
   */
  public ListIterator listIterateLeaf()
  { 
    return this.m_leafList.listIterator(); 
  }

  /**
   * Accessor: Enumerates the internal values that constitute the content
   * of the <code>Scalar</code> element.
   *
   * @param start is the start index
   * @return an enumeration to walk the list with.
   */
  public ListIterator listIterateLeaf(int start)
  { 
    return this.m_leafList.listIterator(start); 
  }

  /**
   * Accessor: Removes all values from this commandline group.
   */
  public void removeAllLeaf()
  {
    this.m_leafList.clear(); 
  }

  /**
   * Accessor: Removes a specific fragment from this commandline group.
   * @param index is the position at which an element is to be removed.
   * @return the object that was removed. The removed item is either an
   *         <code>Use</code> or a <code>Text</code>.
   *
   * @see Use
   * @see Text
   */
  public Leaf removeLeaf( int index )
  {
    return (Leaf) this.m_leafList.remove(index);
  }

  /**
   * Accessor: Overwrites a <code>Use</code> or <code>Text</code> value
   * fragment at a certain position in this command line group.
   * 
   * @param index position to overwrite an elment in.
   * @param vLeaf is either a <code>Use</code> or <code>Text</code> object.
   * @throws IndexOutOfBoundsException if the position pointed to is invalid.
   * @throws IllegalArgumentException if the added element is of the
   *         incorrect <code>Leaf</code> type.
   *
   * @see Use
   * @see Text
   */
  public void setLeaf(int index, Leaf vLeaf)
    throws IndexOutOfBoundsException, IllegalArgumentException
  {
    //-- check bounds for index
    if ((index < 0) || (index >= this.m_leafList.size())) {
      throw new IndexOutOfBoundsException();
    }
    if ( vLeaf instanceof Text || vLeaf instanceof Use )
      this.m_leafList.set(index, vLeaf);
    else
      throw new IllegalArgumentException( c_error_message );
  } //-- void setLeaf(int, Leaf) 

  /**
   * Accessor: Replaces the commandline group with another group value.
   * Warning: The replacements are not checked for being of the correct
   * leaf types.
   *
   * @param leafArray is the external list of <code>Text</code> or
   *        <code>Use</code> objects used to overwrite things.
   * @see Text
   * @see Use
   * @deprecated Use the new Collection based interfaces
   */
  public void setLeaf(Leaf[] leafArray)
  {
    this.m_leafList.clear();
    this.m_leafList.addAll( Arrays.asList(leafArray) );
  }

  /**
   * Accessor: Overwrites internal list with an external list representing
   * a <code>Scalar</code> value.
   *
   * @param leaves is the external list of <code>Text</code> or
   *        <code>LFN</code> objects used to overwrite things.
   * @see Text
   * @see LFN
   */
  public void setLeaf(Collection leaves)
  {
    this.m_leafList.clear();
    this.m_leafList.addAll(leaves);
  }

  /**
   * Accessor: Replaces or sets the current identifier for this
   * commandline group.
   * @param name is the new identifier to use for this commandline group.
   * @see #getName()
   */
  public void setName( String name )
  {
    this.m_name = name; 
  }
  
  /**
   * Converts the commandline group into textual format for human
   * consumption.
   *
   * @param stream is a stream opened and ready for writing. This can also
   * be a string stream for efficient output.
   * @exception IOException if something fishy happens to the stream.
   */
  public void toString( Writer stream )
    throws IOException
  {
    stream.write( "argument" );
    if ( this.m_name != null ) {
      stream.write(' ');
      stream.write(escape(this.m_name));
    }

    stream.write(" = ");
    for ( Iterator i=this.m_leafList.iterator(); i.hasNext(); ) {
      ((Leaf) i.next()).toString(stream);
    }
  }

  /**
   * 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, if you use a buffered writer.
   *
   * @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 newline = System.getProperty( "line.separator", "\r\n" );
    String tag = ( namespace != null && namespace.length() > 0 ) ?
      namespace + ":argument" : "argument";

    // open tag
    if ( indent != null && indent.length() > 0 ) stream.write( indent );
    stream.write( '<' );
    stream.write( tag );
    writeAttribute( stream, " name=\"", this.m_name ); // null-safe
    stream.write( '>' );
    if ( indent != null ) stream.write( newline );

    // dump content
    String newindent = indent==null ? null : indent + "  ";
    for ( Iterator i=this.m_leafList.iterator(); i.hasNext(); ) {
      ((Leaf) i.next()).toXML( stream, newindent, namespace );
    }

    // close tag
    if ( indent != null && indent.length() > 0 ) stream.write( indent );
    stream.write( "</" );
    stream.write( tag );
    stream.write( '>' );
    if ( indent != null ) stream.write( newline );
  }
}