-
- All Superinterfaces:
- AutoCloseable, DataLine, Line
public interface TargetDataLine extends DataLine
A target data line is a type of
from which audio data can be read. The most common example is a data line that gets its data from an audio capture device. (The device is implemented as a mixer that writes to the target data line.)DataLine
Note that the naming convention for this interface reflects the relationship between the line and its mixer. From the perspective of an application, a target data line may act as a source for audio data.
The target data line can be obtained from a mixer by invoking the
method ofgetLine
Mixer
with an appropriate
object.DataLine.Info
The
TargetDataLine
interface provides a method for reading the captured data from the target data line's buffer.Applications that record audio should read data from the target data line quickly enough to keep the buffer from overflowing, which could cause discontinuities in the captured data that are perceived as clicks. Applications can use the
method defined in theavailable
DataLine
interface to determine the amount of data currently queued in the data line's buffer. If the buffer does overflow, the oldest queued data is discarded and replaced by new data.- Since:
- 1.3
- See Also:
Mixer
,DataLine
,SourceDataLine
-
-
Nested Class Summary
-
Nested classes/interfaces inherited from interface javax.sound.sampled.DataLine
DataLine.Info
-
-
Method Summary
Methods Modifier and Type Method and Description void
open(AudioFormat format)
Opens the line with the specified format, causing the line to acquire any required system resources and become operational.void
open(AudioFormat format, int bufferSize)
Opens the line with the specified format and requested buffer size, causing the line to acquire any required system resources and become operational.int
read(byte[] b, int off, int len)
Reads audio data from the data line's input buffer.-
Methods inherited from interface javax.sound.sampled.DataLine
available, drain, flush, getBufferSize, getFormat, getFramePosition, getLevel, getLongFramePosition, getMicrosecondPosition, isActive, isRunning, start, stop
-
Methods inherited from interface javax.sound.sampled.Line
addLineListener, close, getControl, getControls, getLineInfo, isControlSupported, isOpen, open, removeLineListener
-
-
-
-
Method Detail
-
open
void open(AudioFormat format, int bufferSize) throws LineUnavailableException
Opens the line with the specified format and requested buffer size, causing the line to acquire any required system resources and become operational.The buffer size is specified in bytes, but must represent an integral number of sample frames. Invoking this method with a requested buffer size that does not meet this requirement may result in an IllegalArgumentException. The actual buffer size for the open line may differ from the requested buffer size. The value actually set may be queried by subsequently calling
DataLine.getBufferSize()
If this operation succeeds, the line is marked as open, and an
event is dispatched to the line's listeners.OPEN
Invoking this method on a line that is already open is illegal and may result in an
IllegalStateException
.Some lines, once closed, cannot be reopened. Attempts to reopen such a line will always result in a
LineUnavailableException
.- Parameters:
format
- the desired audio formatbufferSize
- the desired buffer size, in bytes.- Throws:
LineUnavailableException
- if the line cannot be opened due to resource restrictionsIllegalArgumentException
- if the buffer size does not represent an integral number of sample frames, or ifformat
is not fully specified or invalidIllegalStateException
- if the line is already openSecurityException
- if the line cannot be opened due to security restrictions- See Also:
open(AudioFormat)
,Line.open()
,Line.close()
,Line.isOpen()
,LineEvent
-
open
void open(AudioFormat format) throws LineUnavailableException
Opens the line with the specified format, causing the line to acquire any required system resources and become operational.The implementation chooses a buffer size, which is measured in bytes but which encompasses an integral number of sample frames. The buffer size that the system has chosen may be queried by subsequently calling
DataLine.getBufferSize()
If this operation succeeds, the line is marked as open, and an
event is dispatched to the line's listeners.OPEN
Invoking this method on a line that is already open is illegal and may result in an
IllegalStateException
.Some lines, once closed, cannot be reopened. Attempts to reopen such a line will always result in a
LineUnavailableException
.- Parameters:
format
- the desired audio format- Throws:
LineUnavailableException
- if the line cannot be opened due to resource restrictionsIllegalArgumentException
- ifformat
is not fully specified or invalidIllegalStateException
- if the line is already openSecurityException
- if the line cannot be opened due to security restrictions- See Also:
open(AudioFormat, int)
,Line.open()
,Line.close()
,Line.isOpen()
,LineEvent
-
read
int read(byte[] b, int off, int len)
Reads audio data from the data line's input buffer. The requested number of bytes is read into the specified array, starting at the specified offset into the array in bytes. This method blocks until the requested amount of data has been read. However, if the data line is closed, stopped, drained, or flushed before the requested amount has been read, the method no longer blocks, but returns the number of bytes read thus far.The number of bytes that can be read without blocking can be ascertained using the
method of theavailable
DataLine
interface. (While it is guaranteed that this number of bytes can be read without blocking, there is no guarantee that attempts to read additional data will block.)The number of bytes to be read must represent an integral number of sample frames, such that:
[ bytes read ] % [frame size in bytes ] == 0
The return value will always meet this requirement. A request to read a number of bytes representing a non-integral number of sample frames cannot be fulfilled and may result in an IllegalArgumentException.- Parameters:
b
- a byte array that will contain the requested input data when this method returnsoff
- the offset from the beginning of the array, in byteslen
- the requested number of bytes to read- Returns:
- the number of bytes actually read
- Throws:
IllegalArgumentException
- if the requested number of bytes does not represent an integral number of sample frames. or iflen
is negative.ArrayIndexOutOfBoundsException
- ifoff
is negative, oroff+len
is greater than the length of the arrayb
.- See Also:
SourceDataLine.write(byte[], int, int)
,DataLine.available()
-
-
Traduction non disponible
Les API Java ne sont pas encore traduites en français sur l'infobrol. Seule la version anglaise est disponible pour l'instant.
Version en cache
05/11/2024 22:12:46 Cette version de la page est en cache (à la date du 05/11/2024 22:12:46) afin d'accélérer le traitement. Vous pouvez activer le mode utilisateur dans le menu en haut pour afficher la dernère version de la page.Document créé le 31/08/2006, dernière modification le 04/03/2020
Source du document imprimé : https://www.gaudry.be/java-api-rf-javax/sound/sampled/TargetDataLine.html
L'infobrol est un site personnel dont le contenu n'engage que moi. Le texte est mis à disposition sous licence CreativeCommons(BY-NC-SA). Plus d'info sur les conditions d'utilisation et sur l'auteur.
Références
Ces références et liens indiquent des documents consultés lors de la rédaction de cette page, ou qui peuvent apporter un complément d'information, mais les auteurs de ces sources ne peuvent être tenus responsables du contenu de cette page.
L'auteur de ce site est seul responsable de la manière dont sont présentés ici les différents concepts, et des libertés qui sont prises avec les ouvrages de référence. N'oubliez pas que vous devez croiser les informations de sources multiples afin de diminuer les risques d'erreurs.