org.mmbase.util.magicfile

Class MagicFile

java.lang.Object

org.mmbase.util.magicfile.MagicFile

public class MagicFile
extends Object

Tries to determine the mime-type of an input stream (getMimeType(InputStream)) (or a file getMimeType(File)). It uses for that a bunch of Detector, which are all configured via a configuratin file 'magic.xml', that you can find as a resource the jar as org/mmbase/config/magic.xml (you could (temporary) override it if you need an improvement in that XML). Several algoritms are used to determin this mime-type. It can use 'magic' bytes sequences as also is done by the unix 'file' utility. Most recognized file types are determined in that manner BasicDetector). XML based file types can also be determined by trying the parse the file as an XML and check for certain XML-namespaces or public ids of the DTD (see XmlDetector). To recognize some other formats (noticebly microsoft office formats) there is now also recognition based on the contents of zip-files. So it wil be tried to treat the stream as a zip-file and if that succeeds, it is checked wether certain 'magic' files are present in it (see ZipDetector).

Version:

$Id$

Author:

cjr@dds.nl, Michiel Meeuwissen

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	BUFSIZE
protected DetectorProvider	detectors
static String	FAILED A constant that is used as a return value for several methods in this class to indidate that determining a mime type failed.

Method Summary

Modifier and Type	Method and Description
String	extensionToMimeType(String extension) Given a file's extension returns its mimetype (e.g.
List<Detector>	getDetectors() Returns a list of detectors used by this MagicFile instance
static MagicFile	getInstance() Return the current instance of MagicFile.
String	getMimeType(byte[] input)
protected String	getMimeType(byte[] input, InputStream in) Tests the byte[] array for the mime type.
String	getMimeType(byte[] data, String extension)
String	getMimeType(File file) Determins what kind of file the given file represents.
String	getMimeType(InputStream input) Determins what kind of file the given input stream represents.
static void	main(String[] argv) e.g.: java -Dmmbase.config=/home/mmbase/mmbase-app/WEB-INF/config org.mmbase.util.MagicFile test.doc
String	mimeTypeToExtension(String mimeType) Given a mime-type string, this function tries to create a common extension for it.
protected String	test(String path)

Methods inherited from class java.lang.Object

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

Field Detail

BUFSIZE

protected static final int BUFSIZE

See Also:

Constant Field Values

FAILED

public static final String FAILED

A constant that is used as a return value for several methods in this class to indidate that determining a mime type failed.

See Also:

Constant Field Values

detectors

protected final DetectorProvider detectors

Method Detail

getInstance

public static MagicFile getInstance()

Return the current instance of MagicFile. If no instance exists, one is created.

getDetectors

public List<Detector> getDetectors()

Returns a list of detectors used by this MagicFile instance

test

protected String test(String path)

getMimeType

public String getMimeType(File file)
                   throws IOException

Determins what kind of file the given file represents. It first considers the contents of the file using getMimeType(InputStream). If that fails the extension of the file name is used via extensionToMimeType(java.lang.String) to guess the file's type.

Parameters:

file - Location of file to be checked

Returns:

Type of the file as determined by the magic file

Throws:

IOException

getMimeType

protected String getMimeType(byte[] input,
                             InputStream in)
                      throws IOException

Tests the byte[] array for the mime type.

Returns:

The found mime-type or FAILED

Throws:

IOException

Since:

MMBase-2.0

getMimeType

public String getMimeType(byte[] input)

getMimeType

public String getMimeType(InputStream input)
                   throws IOException

Determins what kind of file the given input stream represents.

Returns:

The found mime-type or FAILED

Throws:

IOException

Since:

MMBase-1.9.2

extensionToMimeType

public String extensionToMimeType(String extension)

Given a file's extension returns its mimetype (e.g. image/png).

Returns:

A mimetype string or FAILED.

mimeTypeToExtension

public String mimeTypeToExtension(String mimeType)

Given a mime-type string, this function tries to create a common extension for it.

Returns:

An extension (without the dot), or an empty string if the mime-type is unknown, or '???' if no valid extension for it is found.

Since:

MMBase-1.7.1

getMimeType

public String getMimeType(byte[] data,
                          String extension)

Javadoc:

main

public static void main(String[] argv)

e.g.: java -Dmmbase.config=/home/mmbase/mmbase-app/WEB-INF/config org.mmbase.util.MagicFile test.doc

Javadoc: