manager.java

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 *     audio_type      = bitrate_variable / other_type
 *     other_type      = alphanumeric
 *     pos_integer     = 1*DIGIT
 *
 *   and
 *     <a href="#content-type">content type</a> is given in the MIME syntax.
 * </pre>
 *   <br>
 *   &nbsp;&nbsp;&nbsp;&nbsp;Example:
 *   <br>
 * <pre>
 *     encoding=pcm&rate=11025&bits=16&channels=1
 * </pre>
 *
 * <a name="video_encodings"></a>
 * &nbsp;&nbsp;C. Describing the video or image encodings:<p>
 * <pre>
 *     video_encodings   = video_enc_param *( "&" video_param )
 *     video_enc_param   = "encoding=" video_enc
 *     video_enc         = "gray8" / "rgb888" / "bgr888" /
 *                         "rgb565" / "rgb555" / "yuv444" /
 *                         "yuv422" / "yuv420" / "jpeg" / "png" /
 *                         content_type
 *     video_param       = "width=" width /
 *                         "height=" height /
 *                         "fps=" fps /
 *                         "colors=" colors /
 *                         "progressive=" progressive /
 *                         "interlaced=" interlaced /
 *                         "type=" video_type
 *     width             = pos_integer
 *     height            = pos_integer
 *     fps               = pos_number
 *     quality           = pos_integer
 *     colors            = "p" colors_in_palette /
 *                       = "rgb" r_bits g_bits b_bits /
 *                       = "gray" gray_bits
 *     colors_in_palette = pos_integer
 *     r_bits            = pos_integer
 *     g_bits            = pos_integer
 *     b_bits            = pos_integer
 *     gray_bits         = pos_integer
 *     progressive       = boolean
 *     video_type        = jfif / exif / other_type
 *     other_type        = alphanumeric
 *     interlaced        = boolean
 *     pos_number        = 1*DIGIT [ "." 1*DIGIT ]
 *     boolean           = "true" / "false"
 *
 *   and
 *     <a href="#content-type">content type</a> is given in the MIME syntax.
 * </pre>
 *   <br>
 *   &nbsp;&nbsp;&nbsp;&nbsp;Examples:
 *   <br>
 * <pre>
 *     encoding=gray8&width=160&height=120
 *     encoding=jpeg&quality=80&progressive=true&type=jfif
 *         (progressive JPEG with quality 80 in jfif format)
 *     encoding=jpeg&type=exif
 *         (JPEG in exif format)
 *     encoding=png&colors=rgb888
 *         (24 bits/pixel PNG)
 *     encoding=rgb888
 *         (raw 24-bit rgb image)
 *     encoding=rgb&colors=rgb888
 *         (raw 24-bit rgb image)
 * </pre>
 *
 * <a name="mixed_params"></a>
 * &nbsp;&nbsp;D. Describing mixed audio and video encodings:<p>
 * <pre>
 *     mixed_encodings = audio_encodings "&" video_encodings
 * </pre>
 *   <br>
 *   &nbsp;&nbsp;&nbsp;&nbsp;Example:
 *   <br>
 * <pre>
 *     encoding=pcm&encoding=gray8&width=160&height=160
 * </pre>
 *
 * &nbsp;&nbsp;E. Describing custom media encodings:<p>
 * <pre>
 *     custom_encodings = custom_enc_param *( "&" param )
 *     custom_enc_param = "encoding=" value
 *     param            = key "=" value
 *     key              = alphanumeric
 *     value            = alphanumeric
 * </pre>
 *
 * <a name="encodings_rules"></a>
 * &nbsp;&nbsp;F. Rules for handling the encodings strings:<p>
 * <ul>
 * <li> If a given parameter is a custom parameter and is not recognizable
 *      by the implementation, the parameter is treated as an illegal
 *      parameter and the method must throw an appropriate Exception
 *      to denote that.
 * <li> If the value for a given parameter is incorrect because it is
 *      syntactically wrong or illegal (e.g. out of range),
 *      the method must throw an appropriate Exception to denote that.
 * </ul>
 *
 * @created    January 13, 2005
 * @see        javax.microedition.media.protocol.DataSource
 * @see        Player
 * @see        TimeBase
 */

public final class Manager {
    
    /**
     * The locator to create a tone <code>Player</code>
     * to play back tone sequences.  For example,
     * <pre>
     * try {
     *     Player p = Manager.createPlayer(Manager.TONE_DEVICE_LOCATOR);
     *     p.realize();
     *     ToneControl tc = (ToneControl)p.getControl("ToneControl");
     *     tc.setSequence(mySequence);
     *     p.start();
     * } catch (IOException ioe) {
     * } catch (MediaException me) {}
     * </pre>
     *
     * If a tone sequence is not set on the tone
     * <code>Player</code> via its <code>ToneControl</code>,
     * the <code>Player</code> does not carry any
     * sequence.  <code>getDuration</code> returns 0 for this
     * <code>Player</code>.
     * <p>
     * The content type of the <code>Player</code> created from this
     * locator is <code>audio/x-tone-seq</code>.
     * <p>
     * A <code>Player</code> for this locator may not be supported
     * for all implementations.
     * <p>
     * Value "device://tone" is assigned to <code>TONE_DEVICE_LOCATOR</code>.
     */
    public final static String TONE_DEVICE_LOCATOR = "device://tone";

    // private final static String RADIO_CAPTURE_LOCATOR = "capture://radio";

    private final static String DS_ERR = "Cannot create a DataSource for: ";    

    private final static String PL_ERR = "Cannot create a Player for: ";
    
    private final static String REDIRECTED_MSG = " with exception message: ";


    /**
     * This private constructor keeps anyone from actually
     * getting a <CODE>Manager</CODE>.
     */
    private Manager() { }


    /**
     * Return the list of supported content types for the given protocol.
     * <p>
     * See <a href="#content-type">content types</a> for the syntax
     * of the content types returned.
     * See <a href="#media-protocol">protocol name</a> for the syntax
     * of the protocol used.
     * <p>
     * For example, if the given <code>protocol</code>
     * is <code>"http"</code>,
     * then the supported content types that can be played back
     * with the <code>http</code> protocol will be returned.
     * <p>
     * If <code>null</code> is passed in as the <code>protocol</code>,
     * all the supported content types for this implementation
     * will be returned.  The returned array must be non-empty.
     * <p>
     * If the given <code>protocol</code> is an invalid or
     * unsupported protocol, then an empty array will be returned.
     *
     * @param  protocol  The input protocol for the supported content types.
     * @return           The list of supported content types for the given protocol.
     */
    public static String[] getSupportedContentTypes(String protocol) {
        return new String[0];        
    }


    /**
     * Return the list of supported protocols given the content
     * type.  The protocols are returned
     * as strings which identify what locators can be used for creating
     * <code>Player</code>'s.
     * <p>
     * See <a href="#media-protocol">protocol name</a> for the syntax
     * of the protocols returned.
     * See <a href="#content-type">content types</a> for the syntax
     * of the content type used.
     * <p>
     * For example, if the given <code>content_type</code>
     * is <code>"audio/x-wav"</code>, then the supported protocols
     * that can be used to play back <code>audio/x-wav</code>
     * will be returned.
     * <p>
     * If <code>null</code> is passed in as the
     * <code>content_type</code>,
     * all the supported protocols for this implementation
     * will be returned.  The returned array must be non-empty.
     * <p>
     * If the given <code>content_type</code> is an invalid or
     * unsupported content type, then an empty array will be returned.
     *
     * @param  content_type  The content type for the supported protocols.
     * @return               The list of supported protocols for the given content type.
     */
    public static String[] getSupportedProtocols(String content_type) {
        return new String[0];
    }

    /**
     * Create a <code>Player</code> from an input locator.
     *
     * @param  locator                       A locator string in URI syntax that describes
     * the media content.
     * @return                               A new <code>Player</code>.
     * @exception  MediaException            Thrown if a <code>Player</code> cannot
     * be created for the given locator.
     * @exception  IOException               Thrown if there was a problem connecting
     * with the source pointed to by the <code>locator</code>.
     */
    public static Player createPlayer(String locator)
         throws IOException, MediaException {

        if (locator == null) {
            throw new IllegalArgumentException();
        }

        throw new MediaException("Cannot create Player");
    }


    /**
     * Create a <code>Player</code> to play back media from an
     * <code>InputStream</code>.
     * <p>
     * The <code>type</code> argument
     * specifies the content-type of the input media.  If
     * <code>null</code> is given, <code>Manager</code> will
     * attempt to determine the type.  However, since determining
     * the media type is non-trivial for some media types, it
     * may not be feasible in some cases.  The
     * <code>Manager</code> may throw a <code>MediaException</code>
     * to indicate that.
     *
     * @param  stream                        The <code>InputStream</code> that delivers the
     * input media.
     * @param  type                          The <code>ContentType</code> of the media.
     * @return                               A new <code>Player</code>.
     * @exception  MediaException            Thrown if a <code>Player</code> cannot
     * be created for the given stream and type.
     * @exception  IOException               Thrown if there was a problem reading data
     * from the <code>InputStream</code>.
     */
    public static Player createPlayer(InputStream stream, String type)
         throws IOException, MediaException {
        if (stream == null) {
            throw new IllegalArgumentException();
        }

        if (type == null) {
            throw new MediaException(PL_ERR + "NULL content-type");
        }
        
        throw new MediaException("Cannot create Player");

    }


    /**
     * Play back a tone as specified by a note and its duration.
     * A note is given in the range of 0 to 127 inclusive.  The frequency
     * of the note can be calculated from the following formula:
     * <pre>
     *     SEMITONE_CONST = 17.31234049066755 = 1/(ln(2^(1/12)))
     *     note = ln(freq/8.176)*SEMITONE_CONST
     *     The musical note A = MIDI note 69 (0x45) = 440 Hz.
     * </pre>
     * This call is a non-blocking call. Notice that this method may
     * utilize CPU resources significantly on devices that don't
     * have hardware support for tone generation.
     *
     * @param  note                          Defines the tone of the note as specified by the
     * above formula.
     * @param  duration                      The duration of the tone in milli-seconds.
     * Duration must be positive.
     * @param  volume                        Audio volume range from 0 to 100.  100 represents
     * the maximum
     * volume at the current hardware level.  Setting the volume to a
     * value less
     * than 0 will set the volume to 0.  Setting the volume to greater than
     * 100 will set the volume to 100.
     * @exception  MediaException            Thrown if the tone cannot be played
     * due to a device-related problem.
     */
    public static void playTone(int note, int duration, int volume)
         throws MediaException {
        
        if (note < 0 || note > 127 || duration <= 0) {
            throw new IllegalArgumentException("bad param");
        }
    }
}