MidiFileFormat.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package javax.sound.midi;

import java.io.InputStream;
import java.io.IOException;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;


/**
 * A <code>MidiFileFormat</code> object encapsulates a MIDI file's
 * type, as well as its length and timing information.
 *
 * <p>A <code>MidiFileFormat</code> object can
 * include a set of properties. A property is a pair of key and value:
 * the key is of type <code>String</code>, the associated property
 * value is an arbitrary object.
 * Properties specify additional informational
 * meta data (like a author, or copyright).
 * Properties are optional information, and file reader and file
 * writer implementations are not required to provide or
 * recognize properties.
 *
 * <p>The following table lists some common properties that should
 * be used in implementations:
 *
 * <table border=1>
    <caption>MIDI File Format Properties</caption>
 *  <tr>
 *   <th>Property key</th>
 *   <th>Value type</th>
 *   <th>Description</th>
 *  </tr>
 *  <tr>
 *   <td>&quot;author&quot;</td>
 *   <td>{@link java.lang.String String}</td>
 *   <td>name of the author of this file</td>
 *  </tr>
 *  <tr>
 *   <td>&quot;title&quot;</td>
 *   <td>{@link java.lang.String String}</td>
 *   <td>title of this file</td>
 *  </tr>
 *  <tr>
 *   <td>&quot;copyright&quot;</td>
 *   <td>{@link java.lang.String String}</td>
 *   <td>copyright message</td>
 *  </tr>
 *  <tr>
 *   <td>&quot;date&quot;</td>
 *   <td>{@link java.util.Date Date}</td>
 *   <td>date of the recording or release</td>
 *  </tr>
 *  <tr>
 *   <td>&quot;comment&quot;</td>
 *   <td>{@link java.lang.String String}</td>
 *   <td>an arbitrary text</td>
 *  </tr>
 * </table>
 *
 * @see MidiSystem#getMidiFileFormat(java.io.File)
 * @see Sequencer#setSequence(java.io.InputStream stream)
 *
 * @author Kara Kytle
 * @author Florian Bomers
 */

public class MidiFileFormat {


    /**
     * Represents unknown length.
     * @see #getByteLength
     * @see #getMicrosecondLength
     */
    public static final int UNKNOWN_LENGTH = -1;


    /**
     * The type of MIDI file.
     */
    protected int type;

    /**
     * The division type of the MIDI file.
     *
     * @see Sequence#PPQ
     * @see Sequence#SMPTE_24
     * @see Sequence#SMPTE_25
     * @see Sequence#SMPTE_30DROP
     * @see Sequence#SMPTE_30
     */
    protected float divisionType;

    /**
     * The timing resolution of the MIDI file.
     */
    protected int resolution;

    /**
     * The length of the MIDI file in bytes.
     */
    protected int byteLength;

    /**
     * The duration of the MIDI file in microseconds.
     */
    protected long microsecondLength;


    /** The set of properties */
    private HashMap<String, Object> properties;


    /**
     * Constructs a <code>MidiFileFormat</code>.
     *
     * @param type the MIDI file type (0, 1, or 2)
     * @param divisionType the timing division type (PPQ or one of the SMPTE types)
     * @param resolution the timing resolution
     * @param bytes the length of the MIDI file in bytes, or UNKNOWN_LENGTH if not known
     * @param microseconds the duration of the file in microseconds, or UNKNOWN_LENGTH if not known
     * @see #UNKNOWN_LENGTH
     * @see Sequence#PPQ
     * @see Sequence#SMPTE_24
     * @see Sequence#SMPTE_25
     * @see Sequence#SMPTE_30DROP
     * @see Sequence#SMPTE_30
     */
    public MidiFileFormat(int type, float divisionType, int resolution, int bytes, long microseconds) {

        this.type = type;
        this.divisionType = divisionType;
        this.resolution = resolution;
        this.byteLength = bytes;
        this.microsecondLength = microseconds;
        this.properties = null;
    }


    /**
     * Construct a <code>MidiFileFormat</code> with a set of properties.
     *
     * @param type         the MIDI file type (0, 1, or 2)
     * @param divisionType the timing division type
     *      (PPQ or one of the SMPTE types)
     * @param resolution   the timing resolution
     * @param bytes the length of the MIDI file in bytes,
     *      or UNKNOWN_LENGTH if not known
     * @param microseconds the duration of the file in microseconds,
     *      or UNKNOWN_LENGTH if not known
     * @param properties  a <code>Map&lt;String,Object&gt;</code> object
     *        with properties
     *
     * @see #UNKNOWN_LENGTH
     * @see Sequence#PPQ
     * @see Sequence#SMPTE_24
     * @see Sequence#SMPTE_25
     * @see Sequence#SMPTE_30DROP
     * @see Sequence#SMPTE_30
     * @since 1.5
     */
    public MidiFileFormat(int type, float divisionType,
                          int resolution, int bytes,
                          long microseconds, Map<String, Object> properties) {
        this(type, divisionType, resolution, bytes, microseconds);
        this.properties = new HashMap<String, Object>(properties);
    }



    /**
     * Obtains the MIDI file type.
     * @return the file's type (0, 1, or 2)
     */
    public int getType() {
        return type;
    }

    /**
     * Obtains the timing division type for the MIDI file.
     *
     * @return the division type (PPQ or one of the SMPTE types)
     *
     * @see Sequence#Sequence(float, int)
     * @see Sequence#PPQ
     * @see Sequence#SMPTE_24
     * @see Sequence#SMPTE_25
     * @see Sequence#SMPTE_30DROP
     * @see Sequence#SMPTE_30
     * @see Sequence#getDivisionType()
     */
    public float getDivisionType() {
        return divisionType;
    }


    /**
     * Obtains the timing resolution for the MIDI file.
     * If the division type is PPQ, the resolution is specified in ticks per beat.
     * For SMTPE timing, the resolution is specified in ticks per frame.
     *
     * @return the number of ticks per beat (PPQ) or per frame (SMPTE)
     * @see #getDivisionType
     * @see Sequence#getResolution()
     */
    public int getResolution() {
        return resolution;
    }


    /**
     * Obtains the length of the MIDI file, expressed in 8-bit bytes.
     * @return the number of bytes in the file, or UNKNOWN_LENGTH if not known
     * @see #UNKNOWN_LENGTH
     */
    public int getByteLength() {
        return byteLength;
    }

    /**
     * Obtains the length of the MIDI file, expressed in microseconds.
     * @return the file's duration in microseconds, or UNKNOWN_LENGTH if not known
     * @see Sequence#getMicrosecondLength()
     * @see #getByteLength
     * @see #UNKNOWN_LENGTH
     */
    public long getMicrosecondLength() {
        return microsecondLength;
    }

    /**
     * Obtain an unmodifiable map of properties.
     * The concept of properties is further explained in
     * the {@link MidiFileFormat class description}.
     *
     * @return a <code>Map&lt;String,Object&gt;</code> object containing
     *         all properties. If no properties are recognized, an empty map is
     *         returned.
     *
     * @see #getProperty(String)
     * @since 1.5
     */
    public Map<String,Object> properties() {
        Map<String,Object> ret;
        if (properties == null) {
            ret = new HashMap<String,Object>(0);
        } else {
            ret = (Map<String,Object>) (properties.clone());
        }
        return (Map<String,Object>) Collections.unmodifiableMap(ret);
    }


    /**
     * Obtain the property value specified by the key.
     * The concept of properties is further explained in
     * the {@link MidiFileFormat class description}.
     *
     * <p>If the specified property is not defined for a
     * particular file format, this method returns
     * <code>null</code>.
     *
     * @param key the key of the desired property
     * @return the value of the property with the specified key,
     *         or <code>null</code> if the property does not exist.
     *
     * @see #properties()
     * @since 1.5
     */
    public Object getProperty(String key) {
        if (properties == null) {
            return null;
        }
        return properties.get(key);
    }


}