code: /**
   * Copyright (c) 2004-2005, Regents of the University of California
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   *
   * 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.
   *
   * Neither the name of the University of California, Los Angeles nor the
   * names of its contributors may be used to endorse or promote products
   * derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS 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 THE COPYRIGHT
   * OWNER OR 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.
   */
  
  package avrora.core;
  
  import avrora.Main;
  import cck.util.Util;
  import java.io.File;
  
  /**
   * The <code>LoadableProgram</code> class represents a reference to a program on the disk.
   * Since the user may want to reload the program (after recompiling it, for example),
   * this class supports the ability to reload the program from disk.
   *
   * @author Ben L. Titzer
   */
  public class LoadableProgram {
  
      public final String fname;
      public final File file;
      protected Program program;
  
      /**
       * The constructor for the <code>LoadableProgram</code> class creates a new instance with
       * a reference to the file on the disk. The program is NOT automatically loaded.
       * @param f the file containing the program
       */
      public LoadableProgram(File f) {
          file = f;
          fname = f.getAbsolutePath();
      }
  
      /**
       * The constructor for the <code>LoadableProgram</code> class creates a new instance with
       * a reference to the file on the disk. The program is NOT automatically loaded.
       * @param fname the filename of the file containing the program
       */
      public LoadableProgram(String fname) {
          file = new File(fname);
          this.fname = fname;
      }
  
      /**
       * The <code>getProgram()</code> method gets the current representation of the program stored
       * in this object. It will NOT load the program if it has not been loaded yet.
       * @return A program representing a "compiled" version of the file
       */
      public Program getProgram() {
          if ( program == null )
              throw Util.failure("Program "+file+" must be loaded before use");
          return program;
      }
  
      /**
       * The <code>load()</code> method loads (or reloads) the program from the disk.
       */
      public void load() throws Exception {
          program = Main.loadProgram(new String[] { fname });
      }
  
      /**
       * The <code>getName()</code> method returns the name of the program, i.e. the name of the file
       * containing the program.
       * @return the name of the file without its absolute path
       */
      public String getName() {
          return file.getName();
      }
  }
  