1	// WISEList.java
     2	//
     3	// For final project, cs110. 
     4	// Based on example in exam2
     5	// Ethan Bolker  Spring 2004
     6	
     7	import java.util.*;
     8	import java.io.*;
     9	
    10	/**
    11	 * This abstract class wraps a TreeMap, providing Map
    12	 * functionality for WISE maps.
    13	 */
    14	public abstract class WISEList
    15	{
    16	    private String name;
    17	    private Map elements = new TreeMap();
    18	
    19	    /**
    20	     * Create an empty WISEList.
    21	     */
    22	    public WISEList( String name )
    23	    {
    24		this.name = name;
    25	    }
    26	    
    27	    /**
    28	     * Create a WISEList; populate it by reading a file.
    29	     *
    30	     * @param fileName the file to read.
    31	     */
    32	    public WISEList( String name, String fileName )
    33		throws WISEException
    34	    {
    35		this(name);
    36	        BufferedReader inStream  = null;
    37	        try {
    38	            // open the file
    39	            inStream =  new BufferedReader(new FileReader(fileName));
    40	
    41	            // parse a line at a time
    42		    String line;
    43	            while ((line = inStream.readLine()) != null) {
    44			line = line.trim();
    45			if (( line.length() == 0 ) || line.startsWith("#") ) {
    46			    continue;
    47			}
    48			WISEObject obj = parseLine( new StringTokenizer(line) ); 
    49			this.put( obj );
    50	            }
    51	        }
    52	        catch (Exception e) {
    53		    throw new WISEException( e.toString() );
    54	        }
    55	        finally { // close the file
    56	            try {
    57			inStream.close();
    58	            }
    59	            catch (Exception e) {
    60			throw new WISEException( e.toString() );
    61	            }
    62	        }
    63	    }
    64	
    65	    /**
    66	     * Abstract parseLine method is written in each subclass, 
    67	     * since Student, Course and Professor lines are different.
    68	     */
    69	    public abstract WISEObject parseLine( StringTokenizer st )
    70		throws WISEException;
    71	
    72	    // Standard Map management tools
    73	    public void put( WISEObject obj ) 
    74	    {
    75		elements.put(obj.getName(), obj);
    76	    }
    77	
    78	    public void remove( WISEObject obj )
    79	    {
    80		elements.remove(obj.getName());
    81	    }
    82	
    83	    public Iterator iterator( ) 
    84	    {
    85		return elements.values().iterator();
    86	    }
    87	
    88	    public boolean contains( WISEObject obj )
    89	    {
    90		return elements.containsValue(obj);
    91	    }
    92	
    93	    public int size()
    94	    {
    95		return elements.size();
    96	    }
    97	
    98	    /**
    99	     * Look up a WISEObject on this WISEList
   100	     */
   101	    public WISEObject get( String name )
   102		throws WISEException
   103	    {
   104		WISEObject obj = (WISEObject)elements.get(name);
   105		if (obj == null) {
   106		    throw new WISEException( name + " not found in  " + this.name);
   107		}
   108		return obj;
   109	    }
   110	
   111	    /**
   112	     * Each subclass decides what its header should look like
   113	     * when list is printed.
   114	     */
   115	    public abstract String getHeader( );
   116	
   117	    public String getName()
   118	    {
   119		return name;
   120	    }
   121	   
   122	    public String getPrintableList( )
   123	    {
   124		// should do this with a StringBuffer
   125		String s = getHeader() + '\n';
   126		for (Iterator i = elements.values().iterator(); i.hasNext(); ) {
   127		    s += i.next().toString() + '\n';
   128		}
   129		return s;
   130	    }
   131	}