MidiFileFormat (Java SE 12 & JDK 12 )
Keywords: javax.sound.midi.MidiFileFormat class

Module java.desktop
Package javax.sound.midi

## Class MidiFileFormat

- java.lang.Object
- - javax.sound.midi.MidiFileFormat

-     public class MidiFileFormat
      extends Object

  A `MidiFileFormat` object encapsulates a MIDI file's type, as well as its length and timing information.

  A `MidiFileFormat` object can include a set of properties. A property is a pair of key and value: the key is of type `String`, 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.

  The following table lists some common properties that should be used in implementations:

  MIDI File Format Properties
  Property key | Value type | Description
  --- | --- | ---
  "author" | `String` | name of the author of this file
  "title" | `String` | title of this file
  "copyright" | `String` | copyright message
  "date" | `Date` | date of the recording or release
  "comment" | `String` | an arbitrary text

  See Also:
    `MidiSystem.getMidiFileFormat(java.io.File)`, `Sequencer.setSequence(java.io.InputStream stream)`

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `protected int` | `byteLength` | The length of the MIDI file in bytes.
    `protected float` | `divisionType` | The division type of the MIDI file.
    `protected long` | `microsecondLength` | The duration of the MIDI file in microseconds.
    `protected int` | `resolution` | The timing resolution of the MIDI file.
    `protected int` | `type` | The type of MIDI file.
    `static int` | `UNKNOWN_LENGTH` | Represents unknown length.

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `MidiFileFormat​(int type, float divisionType, int resolution, int bytes, long microseconds)` | Constructs a `MidiFileFormat`.
    `MidiFileFormat​(int type, float divisionType, int resolution, int bytes, long microseconds, Map<String,​Object> properties)` | Construct a `MidiFileFormat` with a set of properties.

  - ### Method Summary

    Modifier and Type | Method | Description
    --- | --- | ---
    `int` | `getByteLength()` | Obtains the length of the MIDI file, expressed in 8-bit bytes.
    `float` | `getDivisionType()` | Obtains the timing division type for the MIDI file.
    `long` | `getMicrosecondLength()` | Obtains the length of the MIDI file, expressed in microseconds.
    `Object` | `getProperty​(String key)` | Obtain the property value specified by the key.
    `int` | `getResolution()` | Obtains the timing resolution for the MIDI file.
    `int` | `getType()` | Obtains the MIDI file type.
    `Map<String,​Object>` | `properties()` | Obtain an unmodifiable map of properties.

    - ### Methods declared in class java.lang.Object

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

- - ### Field Detail

    - #### UNKNOWN_LENGTH

          public static final int UNKNOWN_LENGTH

      Represents unknown length.
      See Also:
        `getByteLength()`, `getMicrosecondLength()`, Constant Field Values

    - #### type

          protected int type

      The type of MIDI file.

    - #### divisionType

          protected float divisionType

      The division type of the MIDI file.
      See Also:
        `Sequence.PPQ`, `Sequence.SMPTE_24`, `Sequence.SMPTE_25`, `Sequence.SMPTE_30DROP`, `Sequence.SMPTE_30`

    - #### resolution

          protected int resolution

      The timing resolution of the MIDI file.

    - #### byteLength

          protected int byteLength

      The length of the MIDI file in bytes.

    - #### microsecondLength

          protected long microsecondLength

      The duration of the MIDI file in microseconds.

  - ### Constructor Detail

    - #### MidiFileFormat

          public MidiFileFormat​(int type,
                                float divisionType,
                                int resolution,
                                int bytes,
                                long microseconds)

      Constructs a `MidiFileFormat`.
      Parameters:
        `type` - the MIDI file type (0, 1, or 2)
        `divisionType` - the timing division type (PPQ or one of the SMPTE types)
        `resolution` - the timing resolution
        `bytes` - the length of the MIDI file in bytes, or `UNKNOWN_LENGTH` if not known
        `microseconds` - the duration of the file in microseconds, or `UNKNOWN_LENGTH` if not known
      See Also:
        `UNKNOWN_LENGTH`, `Sequence.PPQ`, `Sequence.SMPTE_24`, `Sequence.SMPTE_25`, `Sequence.SMPTE_30DROP`, `Sequence.SMPTE_30`

    - #### MidiFileFormat

          public MidiFileFormat​(int type,
                                float divisionType,
                                int resolution,
                                int bytes,
                                long microseconds,
                                Map<String,​Object> properties)

      Construct a `MidiFileFormat` with a set of properties.
      Parameters:
        `type` - the MIDI file type (0, 1, or 2)
        `divisionType` - the timing division type (PPQ or one of the SMPTE types)
        `resolution` - the timing resolution
        `bytes` - the length of the MIDI file in bytes, or `UNKNOWN_LENGTH` if not known
        `microseconds` - the duration of the file in microseconds, or `UNKNOWN_LENGTH` if not known
        `properties` - a `Map<String,Object>` object with properties
      Since:
        1.5
      See Also:
        `UNKNOWN_LENGTH`, `Sequence.PPQ`, `Sequence.SMPTE_24`, `Sequence.SMPTE_25`, `Sequence.SMPTE_30DROP`, `Sequence.SMPTE_30`

  - ### Method Detail

    - #### getType

          public int getType()

      Obtains the MIDI file type.
      Returns:
        the file's type (0, 1, or 2)

    - #### getDivisionType

          public float getDivisionType()

      Obtains the timing division type for the MIDI file.
      Returns:
        the division type (PPQ or one of the SMPTE types)
      See Also:
        `Sequence(float, int)`, `Sequence.PPQ`, `Sequence.SMPTE_24`, `Sequence.SMPTE_25`, `Sequence.SMPTE_30DROP`, `Sequence.SMPTE_30`, `Sequence.getDivisionType()`

    - #### getResolution

          public int getResolution()

      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.
      Returns:
        the number of ticks per beat (PPQ) or per frame (SMPTE)
      See Also:
        `getDivisionType()`, `Sequence.getResolution()`

    - #### getByteLength

          public int getByteLength()

      Obtains the length of the MIDI file, expressed in 8-bit bytes.
      Returns:
        the number of bytes in the file, or `UNKNOWN_LENGTH` if not known
      See Also:
        `UNKNOWN_LENGTH`

    - #### getMicrosecondLength

          public long getMicrosecondLength()

      Obtains the length of the MIDI file, expressed in microseconds.
      Returns:
        the file's duration in microseconds, or `UNKNOWN_LENGTH` if not known
      See Also:
        `Sequence.getMicrosecondLength()`, `getByteLength()`, `UNKNOWN_LENGTH`

    - #### properties

          public Map<String,​Object> properties()

      Obtain an unmodifiable map of properties. The concept of properties is further explained in the `class description`.
      Returns:
        a `Map<String,Object>` object containing all properties. If no properties are recognized, an empty map is returned.
      Since:
        1.5
      See Also:
        `getProperty(String)`

    - #### getProperty

          public Object getProperty​(String key)

      Obtain the property value specified by the key. The concept of properties is further explained in the `class description`.

      If the specified property is not defined for a particular file format, this method returns `null`.

      Parameters:
        `key` - the key of the desired property
      Returns:
        the value of the property with the specified key, or `null` if the property does not exist
      Since:
        1.5
      See Also:
        `properties()`