001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019 020 package javax.activation; 021 022 import java.io.File; 023 024 /** 025 * FileTypeMap is an abstract class that provides a data type interface for files. 026 * 027 * @version $Rev: 467553 $ $Date: 2006-10-25 06:01:51 +0200 (Mi, 25. Okt 2006) $ 028 */ 029 public abstract class FileTypeMap { 030 // we use null here rather than a default because 031 // the constructor for MimetypesFileTypeMap does a lot of I/O 032 private static FileTypeMap defaultFileTypeMap = null; 033 034 /** 035 * Sets the default FileTypeMap for the system. 036 * @param fileMap the new default FileTypeMap 037 * @throws SecurityException if the caller does not have "SetFactory" RuntimePermission 038 */ 039 public static void setDefaultFileTypeMap(FileTypeMap fileMap) { 040 SecurityManager sm = System.getSecurityManager(); 041 if (sm != null) { 042 sm.checkSetFactory(); 043 } 044 defaultFileTypeMap = fileMap; 045 } 046 047 /** 048 * Returns the default FileTypeMap 049 * @return the default FileTYpeMap; if null returns a MimetypesFileTypeMap 050 */ 051 public synchronized static FileTypeMap getDefaultFileTypeMap() { 052 if (defaultFileTypeMap == null) { 053 defaultFileTypeMap = new MimetypesFileTypeMap(); 054 } 055 return defaultFileTypeMap; 056 } 057 058 public FileTypeMap() { 059 } 060 061 public abstract String getContentType(File file); 062 063 public abstract String getContentType(String filename); 064 }