/* |
|
* Copyright (c) 1999, 2003, Oracle and/or its affiliates. All rights reserved. |
|
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
|
* |
|
* This code is free software; you can redistribute it and/or modify it |
|
* under the terms of the GNU General Public License version 2 only, as |
|
* published by the Free Software Foundation. Oracle designates this |
|
* particular file as subject to the "Classpath" exception as provided |
|
* by Oracle in the LICENSE file that accompanied this code. |
|
* |
|
* 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). |
|
* |
|
* You should have received a copy of the GNU General Public License version |
|
* 2 along with this work; if not, write to the Free Software Foundation, |
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
|
* |
|
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
* or visit www.oracle.com if you need additional information or have any |
|
* questions. |
|
*/ |
|
package javax.sound.sampled; |
|
/** |
|
* A source data line is a data line to which data may be written. It acts as |
|
* a source to its mixer. An application writes audio bytes to a source data line, |
|
* which handles the buffering of the bytes and delivers them to the mixer. |
|
* The mixer may mix the samples with those from other sources and then deliver |
|
* the mix to a target such as an output port (which may represent an audio output |
|
* device on a sound card). |
|
* <p> |
|
* Note that the naming convention for this interface reflects the relationship |
|
* between the line and its mixer. From the perspective of an application, |
|
* a source data line may act as a target for audio data. |
|
* <p> |
|
* A source data line can be obtained from a mixer by invoking the |
|
* <code>{@link Mixer#getLine getLine}</code> method of <code>Mixer</code> with |
|
* an appropriate <code>{@link DataLine.Info}</code> object. |
|
* <p> |
|
* The <code>SourceDataLine</code> interface provides a method for writing |
|
* audio data to the data line's buffer. Applications that play or mix |
|
* audio should write data to the source data line quickly enough to keep the |
|
* buffer from underflowing (emptying), which could cause discontinuities in |
|
* the audio that are perceived as clicks. Applications can use the |
|
* <code>{@link DataLine#available available}</code> method defined in the |
|
* <code>DataLine</code> interface to determine the amount of data currently |
|
* queued in the data line's buffer. The amount of data which can be written |
|
* to the buffer without blocking is the difference between the buffer size |
|
* and the amount of queued data. If the delivery of audio output |
|
* stops due to underflow, a <code>{@link LineEvent.Type#STOP STOP}</code> event is |
|
* generated. A <code>{@link LineEvent.Type#START START}</code> event is generated |
|
* when the audio output resumes. |
|
* |
|
* @author Kara Kytle |
|
* @see Mixer |
|
* @see DataLine |
|
* @see TargetDataLine |
|
* @since 1.3 |
|
*/ |
|
public interface SourceDataLine extends DataLine { |
|
/** |
|
* Opens the line with the specified format and suggested buffer size, |
|
* causing the line to acquire any required |
|
* system resources and become operational. |
|
* <p> |
|
* 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 <code>{@link DataLine#getBufferSize}</code>. |
|
* <p> |
|
* If this operation succeeds, the line is marked as open, and an |
|
* <code>{@link LineEvent.Type#OPEN OPEN}</code> event is dispatched to the |
|
* line's listeners. |
|
* <p> |
|
* Invoking this method on a line which is already open is illegal |
|
* and may result in an <code>IllegalStateException</code>. |
|
* <p> |
|
* Note that some lines, once closed, cannot be reopened. Attempts |
|
* to reopen such a line will always result in a |
|
* <code>LineUnavailableException</code>. |
|
* |
|
* @param format the desired audio format |
|
* @param bufferSize the desired buffer size |
|
* @throws LineUnavailableException if the line cannot be |
|
* opened due to resource restrictions |
|
* @throws IllegalArgumentException if the buffer size does not represent |
|
* an integral number of sample frames, |
|
* or if <code>format</code> is not fully specified or invalid |
|
* @throws IllegalStateException if the line is already open |
|
* @throws SecurityException if the line cannot be |
|
* opened due to security restrictions |
|
* |
|
* @see #open(AudioFormat) |
|
* @see Line#open |
|
* @see Line#close |
|
* @see Line#isOpen |
|
* @see LineEvent |
|
*/ |
|
public void open(AudioFormat format, int bufferSize) throws LineUnavailableException; |
|
/** |
|
* Opens the line with the specified format, causing the line to acquire any |
|
* required system resources and become operational. |
|
* |
|
* <p> |
|
* 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 |
|
* <code>{@link DataLine#getBufferSize}</code>. |
|
* <p> |
|
* If this operation succeeds, the line is marked as open, and an |
|
* <code>{@link LineEvent.Type#OPEN OPEN}</code> event is dispatched to the |
|
* line's listeners. |
|
* <p> |
|
* Invoking this method on a line which is already open is illegal |
|
* and may result in an <code>IllegalStateException</code>. |
|
* <p> |
|
* Note that some lines, once closed, cannot be reopened. Attempts |
|
* to reopen such a line will always result in a |
|
* <code>LineUnavailableException</code>. |
|
* |
|
* @param format the desired audio format |
|
* @throws LineUnavailableException if the line cannot be |
|
* opened due to resource restrictions |
|
* @throws IllegalArgumentException if <code>format</code> |
|
* is not fully specified or invalid |
|
* @throws IllegalStateException if the line is already open |
|
* @throws SecurityException if the line cannot be |
|
* opened due to security restrictions |
|
* |
|
* @see #open(AudioFormat, int) |
|
* @see Line#open |
|
* @see Line#close |
|
* @see Line#isOpen |
|
* @see LineEvent |
|
*/ |
|
public void open(AudioFormat format) throws LineUnavailableException; |
|
/** |
|
* Writes audio data to the mixer via this source data line. The requested |
|
* number of bytes of data are read from the specified array, |
|
* starting at the given offset into the array, and written to the data |
|
* line's buffer. If the caller attempts to write more data than can |
|
* currently be written (see <code>{@link DataLine#available available}</code>), |
|
* this method blocks until the requested amount of data has been written. |
|
* This applies even if the requested amount of data to write is greater |
|
* than the data line's buffer size. However, if the data line is closed, |
|
* stopped, or flushed before the requested amount has been written, |
|
* the method no longer blocks, but returns the number of bytes |
|
* written thus far. |
|
* <p> |
|
* The number of bytes that can be written without blocking can be ascertained |
|
* using the <code>{@link DataLine#available available}</code> method of the |
|
* <code>DataLine</code> interface. (While it is guaranteed that |
|
* this number of bytes can be written without blocking, there is no guarantee |
|
* that attempts to write additional data will block.) |
|
* <p> |
|
* The number of bytes to write must represent an integral number of |
|
* sample frames, such that: |
|
* <br> |
|
* <center><code>[ bytes written ] % [frame size in bytes ] == 0</code></center> |
|
* <br> |
|
* The return value will always meet this requirement. A request to write a |
|
* number of bytes representing a non-integral number of sample frames cannot |
|
* be fulfilled and may result in an <code>IllegalArgumentException</code>. |
|
* |
|
* @param b a byte array containing data to be written to the data line |
|
* @param len the length, in bytes, of the valid data in the array |
|
* (in other words, the requested amount of data to write, in bytes) |
|
* @param off the offset from the beginning of the array, in bytes |
|
* @return the number of bytes actually written |
|
* @throws IllegalArgumentException if the requested number of bytes does |
|
* not represent an integral number of sample frames, |
|
* or if <code>len</code> is negative |
|
* @throws ArrayIndexOutOfBoundsException if <code>off</code> is negative, |
|
* or <code>off+len</code> is greater than the length of the array |
|
* <code>b</code>. |
|
* |
|
* @see TargetDataLine#read |
|
* @see DataLine#available |
|
*/ |
|
public int write(byte[] b, int off, int len); |
|
/** |
|
* Obtains the number of sample frames of audio data that can be written to |
|
* the mixer, via this data line, without blocking. Note that the return |
|
* value measures sample frames, not bytes. |
|
* @return the number of sample frames currently available for writing |
|
* @see TargetDataLine#availableRead |
|
*/ |
|
//public int availableWrite(); |
|
} |