javax.microedition.media.control
Interface MetaDataControl

All Superinterfaces:

Control

public interface MetaDataControl

extends Control

MetaDataControl is used to retrieve metadata information included within the media streams. A MetaDataControl object recognizes and stores metadata and provides XML-like accessor methods to retrieve this information.
Predefined keys are provided to refer to commonly used metadata fields (title, copyright, data, author).

Field Summary

static java.lang.String	AUTHOR_KEY Default key for AUTHOR information.
static java.lang.String	COPYRIGHT_KEY Default key for COPYRIGHT information.
static java.lang.String	DATE_KEY Default key for DATE information.
static java.lang.String	TITLE_KEY Default key for TITLE information.

Method Summary

java.lang.String[]	getKeys() Return the list of keys for the available metadata values.
java.lang.String	getKeyValue(java.lang.String key) Retrieve the value found in the metadata associated with the given key.

Field Detail

AUTHOR_KEY

public static final java.lang.String AUTHOR_KEY

Default key for AUTHOR information.

Value "author" is assigned to AUTHOR_KEY.

COPYRIGHT_KEY

public static final java.lang.String COPYRIGHT_KEY

Default key for COPYRIGHT information.

Value "copyright" is assigned to COPYRIGHT_KEY.

DATE_KEY

public static final java.lang.String DATE_KEY

Default key for DATE information.

Value "date" is assigned to DATE_KEY.

TITLE_KEY

public static final java.lang.String TITLE_KEY

Default key for TITLE information.

Value "title" is assigned to TITLE_KEY.

Method Detail

getKeys

public java.lang.String[] getKeys()

Return the list of keys for the available metadata values. The returned array must be an array with at least one key.

Returns:

The list of keys for the available metadata values.

getKeyValue

public java.lang.String getKeyValue(java.lang.String key)

Retrieve the value found in the metadata associated with the given key. Only keys obtained from getKeys are valid and can be used to retrieve metadata values. If null or an invalid key is used, an IllegalArgumentException will be thrown.

Some keys are valid but the associated metadata may not be available before a certain portion of the media is played. For example, some streaming media types may contain metadata that's stored at the end of the file. As a result, the metadata may not be available until the playback reaches the end of media. When that happens, calling getKeyValues with those keys will return null before the data is available. However, when the playback reaches the end of media, all metadata values must be made available.

Parameters:

key - a key to retrieve the value.

Returns:

the value of the key or null if the given key is valid but the value is not yet available.

Throws:

IllegalArgumentException - Thrown if the given key is null or invalid.