FileTypeMap.java

/*
 * FileTypeMap.java
 * Copyright (C) 2004 The Free Software Foundation
 * 
 * This file is part of GNU Java Activation Framework (JAF), a library.
 * 
 * GNU JAF is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * GNU JAF 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * As a special exception, if you link this library with other files to
 * produce an executable, this library does not by itself cause the
 * resulting executable to be covered by the GNU General Public License.
 * This exception does not however invalidate any other reasons why the
 * executable file might be covered by the GNU General Public License.
 */
package javax.activation;

import java.io.File;

/**
 * Classifier for the MIME content type of files.
 *
 * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
 * @version 1.1
 */
public abstract class FileTypeMap
{

  /* Class scope */
  
  private static FileTypeMap defaultMap;
  
  /**
   * Returns the system default file type map.
   * If one has not been set, this returns a MimetypesFileTypeMap.
   */
  public static FileTypeMap getDefaultFileTypeMap()
  {
    if (defaultMap == null)
      {
        defaultMap = new MimetypesFileTypeMap();
      }
    return defaultMap;
  }
  
  /**
   * Sets the default file type map.
   * @param map the new file type map
   */
  public static void setDefaultFileTypeMap(FileTypeMap map)
  {
    SecurityManager security = System.getSecurityManager();
    if (security != null)
      {
        try
          {
            security.checkSetFactory();
          }
        catch (SecurityException e)
          {
            if (map != null && FileTypeMap.class.getClassLoader() !=
                map.getClass().getClassLoader())
              {
                throw e;
              }
          }
      }
    defaultMap = map;
  }

  /* Instance scope */
  
  /**
   * Returns the content type of the specified file.
   * @param file the file to classify
   */
  public abstract String getContentType(File file);
  
  /**
   * Returns the content type of the specified file path.
   * @param filename the path of the file to classify
   */
  public abstract String getContentType(String filename);

}