Package jakarta.activation

Class FileDataSource

java.lang.Object

jakarta.activation.FileDataSource

All Implemented Interfaces:

DataSource

public class FileDataSource
extends Object
implements DataSource

The FileDataSource class implements a simple DataSource object that encapsulates a file. It provides data typing services via a FileTypeMap object.

FileDataSource Typing Semantics

The FileDataSource class delegates data typing of files to an object subclassed from the FileTypeMap class. The setFileTypeMap method can be used to explicitly set the FileTypeMap for an instance of FileDataSource. If no FileTypeMap is set, the FileDataSource will call the FileTypeMap's getDefaultFileTypeMap method to get the System's default FileTypeMap.

See Also:

• DataSource
• FileTypeMap
• MimetypesFileTypeMap

Constructor Summary

Constructors

Constructor	Description
FileDataSource(File file)	Creates a FileDataSource from a File object.
FileDataSource(String name)	Creates a FileDataSource from the specified path name.

Method Summary

Modifier and Type	Method	Description
String	getContentType()	This method returns the MIME type of the data in the form of a string.
File	getFile()	Return the File object that corresponds to this FileDataSource.
InputStream	getInputStream()	This method will return an InputStream representing the the data and will throw an IOException if it can not do so.
String	getName()	Return the name of this object.
OutputStream	getOutputStream()	This method will return an OutputStream representing the the data and will throw an IOException if it can not do so.
void	setFileTypeMap(FileTypeMap map)	Set the FileTypeMap to use with this FileDataSource

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

FileDataSource

public FileDataSource(File file)

Creates a FileDataSource from a File object. Note: The file will not actually be opened until a method is called that requires the file to be opened.

Parameters:

file - the file

FileDataSource

public FileDataSource(String name)

Creates a FileDataSource from the specified path name. Note: The file will not actually be opened until a method is called that requires the file to be opened.

Parameters:

name - the system-dependent file name.

Method Details

getInputStream

public InputStream getInputStream()
                           throws IOException

This method will return an InputStream representing the the data and will throw an IOException if it can not do so. This method will return a new instance of InputStream with each invocation.

Specified by:

getInputStream in interface DataSource

Returns:

an InputStream

Throws:

IOException - for failures creating the InputStream

getOutputStream

public OutputStream getOutputStream()
                             throws IOException

This method will return an OutputStream representing the the data and will throw an IOException if it can not do so. This method will return a new instance of OutputStream with each invocation.

Specified by:

getOutputStream in interface DataSource

Returns:

an OutputStream

Throws:

IOException - for failures creating the OutputStream

getContentType

public String getContentType()

This method returns the MIME type of the data in the form of a string. This method uses the currently installed FileTypeMap. If there is no FileTypeMap explictly set, the FileDataSource will call the getDefaultFileTypeMap method on FileTypeMap to acquire a default FileTypeMap. Note: By default, the FileTypeMap used will be a MimetypesFileTypeMap.

Specified by:

getContentType in interface DataSource

Returns:

the MIME Type

See Also:

• FileTypeMap.getDefaultFileTypeMap()

getName

public String getName()

Return the name of this object. The FileDataSource will return the file name of the object.

Specified by:

getName in interface DataSource

Returns:

the name of the object.

See Also:

• DataSource

getFile

public File getFile()

Return the File object that corresponds to this FileDataSource.

Returns:

the File object for the file represented by this object.

setFileTypeMap

public void setFileTypeMap(FileTypeMap map)

Set the FileTypeMap to use with this FileDataSource

Parameters:

map - The FileTypeMap for this object.