VersionControlCache.java

/*
 *  Author:  Chris Seguin
 *
 *  This software has been developed under the copyleft
 *  rules of the GNU General Public License.  Please
 *  consult the GNU General Public License for more
 *  details about use and distribution of this software.
 */
package org.acm.seguin.version;

import java.util.Hashtable;

/**
 *  Cache of files - so that it doesn't take so long to get the menu 
 *
 *@author     Chris Seguin 
 *@created    June 17, 1999 
 */
public class VersionControlCache {
	//  Instance Variables
	private Hashtable cache;

	/**
	 *  Description of the Field 
	 */
	public final static int ADD = 0;
	/**
	 *  Description of the Field 
	 */
	public final static int CHECK_IN = 1;
	/**
	 *  Description of the Field 
	 */
	public final static int CHECK_OUT = 2;
	/**
	 *  Description of the Field 
	 */
	public final static int CHECK_IN_PROGRESS = 3;
	/**
	 *  Description of the Field 
	 */
	public final static int CHECK_OUT_PROGRESS = 4;
	/**
	 *  Description of the Field 
	 */
	public final static int ADD_PROGRESS = 5;

	//  Class Variables
	private static VersionControlCache ssc = null;


	/**
	 *  Constructor for the VersionControlCache object 
	 */
	protected VersionControlCache() {
		cache = new Hashtable();
	}


	/**
	 *  Looks up a file in the cache 
	 *
	 *@param  filename  Description of Parameter 
	 *@return           The InCache value 
	 */
	public boolean isInCache(String filename) {
		return cache.get(filename) != null;
	}


	/**
	 *  Looks up a file in the cache 
	 *
	 *@param  filename  Description of Parameter 
	 *@return           Description of the Returned Value 
	 */
	public int lookup(String filename) {
		Integer stored = (Integer) cache.get(filename);
		if (stored == null) {
			return ADD;
		}

		return stored.intValue();
	}


	/**
	 *  Add to the cache 
	 *
	 *@param  filename  the name of the file 
	 *@param  type      the state 
	 */
	public void add(String filename, int type) {
		cache.put(filename, new Integer(type));
	}


	/**
	 *  Return the cache 
	 *
	 *@return    the cache 
	 */
	public static VersionControlCache getCache() {
		if (ssc == null) {
			init();
		}

		return ssc;
	}


	/**
	 *  Create a source safe cache 
	 */
	private static synchronized void init() {
		if (ssc == null) {
			ssc = new VersionControlCache();
		}
	}
}