HistoryPath.java

package de.unisiegen.gtitool.ui.history;


import java.util.ArrayList;

import de.unisiegen.gtitool.core.entities.DefaultTransition;
import de.unisiegen.gtitool.core.entities.State;
import de.unisiegen.gtitool.core.entities.Symbol;
import de.unisiegen.gtitool.core.entities.Transition;
import de.unisiegen.gtitool.core.exceptions.transition.TransitionSymbolNotInAlphabetException;
import de.unisiegen.gtitool.core.exceptions.transition.TransitionSymbolOnlyOneTimeException;


/**
 * The history path.
 * 
 * @author Christian Fehler
 * @version $Id$
 */
public final class HistoryPath implements Comparable < HistoryPath >
{

  /**
   * The start {@link State}.
   */
  private State startState;


  /**
   * The {@link Transition} list.
   */
  private ArrayList < Transition > transitionList;


  /**
   * The {@link Symbol} list.
   */
  private ArrayList < Symbol > symbolList;


  /**
   * Allocates a new {@link HistoryPath}.
   */
  public HistoryPath ()
  {
    this.startState = null;
    this.transitionList = new ArrayList < Transition > ();
    this.symbolList = new ArrayList < Symbol > ();
  }


  /**
   * Adds the values to the {@link HistoryPath}.
   * 
   * @param transition The {@link Transition}.
   * @param symbol The {@link Symbol}.
   */
  public final void add ( Transition transition, Symbol symbol )
  {
    if ( ( symbol != null ) && !transition.contains ( symbol ) )
    {
      throw new IllegalArgumentException (
          "the symbol is not a member of the transition" ); //$NON-NLS-1$
    }

    Transition newTransition = new DefaultTransition ();

    newTransition.setStateBegin ( transition.getStateBegin () );
    newTransition.setStateEnd ( transition.getStateEnd () );

    try
    {
      newTransition.replace ( transition.getSymbol () );
    }
    catch ( TransitionSymbolNotInAlphabetException exc )
    {
      exc.printStackTrace ();
      System.exit ( 1 );
      return;
    }
    catch ( TransitionSymbolOnlyOneTimeException exc )
    {
      exc.printStackTrace ();
      System.exit ( 1 );
      return;
    }

    for ( Symbol current : newTransition )
    {
      if ( current.equals ( symbol ) )
      {
        current.setActive ( true );
        break;
      }
    }

    this.transitionList.add ( newTransition );
    this.symbolList.add ( symbol );
  }


  /**
   * {@inheritDoc}
   * 
   * @see Comparable#compareTo(Object)
   */
  public final int compareTo ( HistoryPath other )
  {
    if ( ( this.startState != null ) && ( other.startState != null ) )
    {
      return 0;
    }
    if ( this.startState != null )
    {
      return -1;
    }
    if ( other.startState != null )
    {
      return 1;
    }

    if ( this.transitionList.size () == other.transitionList.size () )
    {
      return 0;
    }
    if ( this.transitionList.size () < other.transitionList.size () )
    {
      return -1;
    }
    if ( this.transitionList.size () > other.transitionList.size () )
    {
      return 1;
    }

    return 0;
  }


  /**
   * Returns the start {@link State}.
   * 
   * @return The start {@link State}.
   * @see #startState
   */
  public final State getStartState ()
  {
    return this.startState;
  }


  /**
   * Returns the {@link Symbol} list.
   * 
   * @return The {@link Symbol} list.
   * @see #symbolList
   */
  public final ArrayList < Symbol > getSymbolList ()
  {
    return this.symbolList;
  }


  /**
   * Returns the {@link Transition} list.
   * 
   * @return The {@link Transition} list.
   * @see #transitionList
   */
  public final ArrayList < Transition > getTransitionList ()
  {
    return this.transitionList;
  }


  /**
   * Sets the start {@link State}.
   * 
   * @param startState The start {@link State} to set.
   * @see #startState
   */
  public final void setStartState ( State startState )
  {
    this.startState = startState;
  }


  /**
   * {@inheritDoc}
   * 
   * @see Object#toString()
   */
  @Override
  public final String toString ()
  {
    StringBuilder result = new StringBuilder ();

    for ( int i = 0 ; i < this.transitionList.size () ; i++ )
    {
      if ( i == 0 )
      {
        result.append ( this.transitionList.get ( i ).getStateBegin ()
            .getName () );
      }
      result.append ( " \u2192 " ); //$NON-NLS-1$
      result.append ( this.transitionList.get ( i ).getStateEnd ().getName () );
    }

    return result.toString ();
  }
}