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/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*/
/*
* @(#)FileTypeMap.java 1.8 05/11/16
*
* Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
*/
package javax.activation;
import java.io.File;
/**
* The FileTypeMap is an abstract class that provides a data typing
* interface for files. Implementations of this class will
* implement the getContentType methods which will derive a content
* type from a file name or a File object. FileTypeMaps could use any
* scheme to determine the data type, from examining the file extension
* of a file (like the MimetypesFileTypeMap) to opening the file and
* trying to derive its type from the contents of the file. The
* FileDataSource class uses the default FileTypeMap (a MimetypesFileTypeMap
* unless changed) to determine the content type of files.
*
* @see javax.activation.FileTypeMap
* @see javax.activation.FileDataSource
* @see javax.activation.MimetypesFileTypeMap
*/
public abstract class FileTypeMap {
private static FileTypeMap defaultMap = null;
/**
* The default constructor.
*/
public FileTypeMap() {
super();
}
/**
* Return the type of the file object. This method should
* always return a valid MIME type.
*
* @param file A file to be typed.
* @return The content type.
*/
abstract public String getContentType(File file);
/**
* Return the type of the file passed in. This method should
* always return a valid MIME type.
*
* @param filename the pathname of the file.
* @return The content type.
*/
abstract public String getContentType(String filename);
/**
* Sets the default FileTypeMap for the system. This instance
* will be returned to callers of getDefaultFileTypeMap.
*
* @param map The FileTypeMap.
* @exception SecurityException if the caller doesn't have permission
* to change the default
*/
public static void setDefaultFileTypeMap(FileTypeMap map) {
SecurityManager security = System.getSecurityManager();
if (security != null) {
try {
// if it's ok with the SecurityManager, it's ok with me...
security.checkSetFactory();
} catch (SecurityException ex) {
// otherwise, we also allow it if this code and the
// factory come from the same class loader (e.g.,
// the JAF classes were loaded with the applet classes).
if (FileTypeMap.class.getClassLoader() !=
map.getClass().getClassLoader())
throw ex;
}
}
defaultMap = map;
}
/**
* Return the default FileTypeMap for the system.
* If setDefaultFileTypeMap was called, return
* that instance, otherwise return an instance of
* MimetypesFileTypeMap.
*
* @return The default FileTypeMap
* @see javax.activation.FileTypeMap#setDefaultFileTypeMap
*/
public static FileTypeMap getDefaultFileTypeMap() {
// XXX - probably should be synchronized
if (defaultMap == null)
defaultMap = new MimetypesFileTypeMap();
return defaultMap;
}
}