| /* |
| * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package javax.activation; |
| |
| import java.io.File; |
| import java.util.Map; |
| import java.util.WeakHashMap; |
| |
| /** |
| * 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 |
| * |
| * @since 1.6 |
| */ |
| |
| public abstract class FileTypeMap { |
| |
| private static FileTypeMap defaultMap = null; |
| private static Map<ClassLoader,FileTypeMap> map = |
| new WeakHashMap<ClassLoader,FileTypeMap>(); |
| |
| /** |
| * 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 fileTypeMap The FileTypeMap. |
| * @exception SecurityException if the caller doesn't have permission |
| * to change the default |
| */ |
| public static synchronized void setDefaultFileTypeMap(FileTypeMap fileTypeMap) { |
| 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 (non-system) class loader (e.g., |
| // the JAF classes were loaded with the applet classes). |
| ClassLoader cl = FileTypeMap.class.getClassLoader(); |
| if (cl == null || cl.getParent() == null || |
| cl != fileTypeMap.getClass().getClassLoader()) |
| throw ex; |
| } |
| } |
| // remove any per-thread-context-class-loader FileTypeMap |
| map.remove(SecuritySupport.getContextClassLoader()); |
| defaultMap = fileTypeMap; |
| } |
| |
| /** |
| * Return the default FileTypeMap for the system. |
| * If setDefaultFileTypeMap was called, return |
| * that instance, otherwise return an instance of |
| * <code>MimetypesFileTypeMap</code>. |
| * |
| * @return The default FileTypeMap |
| * @see javax.activation.FileTypeMap#setDefaultFileTypeMap |
| */ |
| public static synchronized FileTypeMap getDefaultFileTypeMap() { |
| if (defaultMap != null) |
| return defaultMap; |
| |
| // fetch per-thread-context-class-loader default |
| ClassLoader tccl = SecuritySupport.getContextClassLoader(); |
| FileTypeMap def = map.get(tccl); |
| if (def == null) { |
| def = new MimetypesFileTypeMap(); |
| map.put(tccl, def); |
| } |
| return def; |
| } |
| } |