ExtensionRegistry.java #3

/*
 *
 * Perforce/Java Integration Layer
 * Copyright (C) 2001-2002 David Freels
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

package com.dafreels.vcs.util;

//Java
import java.util.List;
import java.util.ArrayList;

/**
 *
 * @author  David Freels
 * @version 1.0
 */
public final class ExtensionRegistry
{
  private static List m_extensions = null;
  private static ExtensionRegistry m_reg = null;

  /** Creates new ExtensionRegistry */
  private ExtensionRegistry()
  {
      // Don't re-initialize the m_extensions ArrayList if it's already
      // been setup.  (Matt Wolinski - 6/4/03)
      if (m_extensions == null)
      {
          m_extensions = new ArrayList(10);
          m_extensions.add("java");
          m_extensions.add("jsp");
          m_extensions.add("html");
          m_extensions.add("htm");
          m_extensions.add("gif");
          m_extensions.add("jpg");
          m_extensions.add("js");
          m_extensions.add("css");
          m_extensions.add("xml");
          m_extensions.add("jsi");
      }
  }

  /**
   * Creates a new instance of the ExtensionRegistry
   * class
   * @param extensions A list of file extensions that the toll will recognize minus the "."
   * @return An instance of the ExtensionRegistry class
   */
  public static ExtensionRegistry newInstance(List extensions)
  {
      // Set the m_extensions ArrayList and overwrite it when it already exists.
      // The list we passed in is the one we want to use. (MJW - 6/4/03)
      ExtensionRegistry.m_extensions = extensions;
      return getInstance();
  }

  /**
   * Gets the singleton instance of this class.
   * @return An instance of the ExtensioRegistry class
   */
  public static ExtensionRegistry getInstance()
  {
	if(m_reg == null)
	{
	  m_reg = new ExtensionRegistry();
	}

	return m_reg;
  }


  /**
   * Validates the filename against the list of
   * valid extensions.
   * @param fileName The filename to validate
   * @return True if the file has a valid extension.
   */
  public boolean validateFile(String fileName)
  {
	if(m_extensions == null) return false;

	return m_extensions.contains(fileName.substring(fileName.lastIndexOf(".") + 1));
  }

}