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Java Platform, Enterprise Edition v1.3.1 API Specifications
Java 2 Platform EE v1.3: Class FileTypeMap - Java Platform, Enterprise Edition v1.3.1 API Specifications
javax.activation
Class FileTypeMap
java.lang.Object
|
+--javax.activation.FileTypeMap
- Direct Known Subclasses:
- MimetypesFileTypeMap
- public abstract class FileTypeMap
- extends java.lang.Object
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 Also:
FileTypeMap
,
FileDataSource
,
MimetypesFileTypeMap
Constructor Summary |
FileTypeMap()
The default constructor. |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
FileTypeMap
public FileTypeMap()
- The default constructor.
getContentType
public abstract java.lang.String getContentType(java.io.File file)
- Return the type of the file object. This method should
always return a valid MIME type.
- Parameters:
f
- A file to be typed.- Returns:
- The content type.
getContentType
public abstract java.lang.String getContentType(java.lang.String filename)
- Return the type of the file passed in. This method should
always return a valid MIME type.
- Parameters:
filename
- the pathname of the file.- Returns:
- The content type.
setDefaultFileTypeMap
public static void setDefaultFileTypeMap(FileTypeMap map)
- Sets the default FileTypeMap for the system. This instance
will be returned to callers of getDefaultFileTypeMap.
- Parameters:
map
- The FileTypeMap.- Throws:
java.lang.SecurityException
- if the caller doesn't have permission
to change the default
getDefaultFileTypeMap
public static FileTypeMap getDefaultFileTypeMap()
- Return the default FileTypeMap for the system.
If setDefaultFileTypeMap was called, return
that instance, otherwise return an instance of
MimetypesFileTypeMap
.
- Returns:
- The default FileTypeMap
- See Also:
setDefaultFileTypeMap(javax.activation.FileTypeMap)