/*
* @(#)DataSource.java 1.7 02/08/21
*
* Copyright (c) 1996-2002 Sun Microsystems, Inc. All rights reserved.
*/
package com.ibm.media.protocol.device;
import java.io.*;
/**
* This is a DataSource that reprents an audio capture device
*/
public class DataSource extends javax.media.protocol.PushDataSource {
/**
* The actual stream
*/
DevicePushSourceStream stream;
/**
* The streams array
*/
DevicePushSourceStream[] streams;
static {
com.sun.media.JMFSecurityManager.loadLibrary("jmdevice");
}
/**
* A no-argument constructor required by pre 1.1 implementations
* so that this class can be instantiated by
* calling <CODE>Class.newInstance</CODE>.
*
*/
public DataSource() {
super();
}
/**
* Get a string that describes the content-type of the media
* that the source is providing.
* <p>
* It is an error to call <CODE>getContentType</CODE> if the source is
* not connected.
*
* @return The name that describes the media content.
*/
public String getContentType() {
// tempotary implementation
return "raw";
}
/**
* Open a connection to the source described by
* the <CODE>MediaLocator</CODE>.
* <p>
*
* The <CODE>connect</CODE> method initiates communication with the source.
*
* @exception IOException Thrown if there are IO problems
* when <CODE>connect</CODE> is called.
*/
public void connect() throws IOException {
System.out.println("connecting DataSource");
// currently we don't use the mediaLocator... we use default device
stream = new DevicePushSourceStream();
streams = new DevicePushSourceStream[1];
streams[0] = stream;
connectDevice();
}
/**
* Connect to the actual device
*/
native void connectDevice();
/**
* Close the connection to the source described by the locator.
* <p>
* The <CODE>disconnect</CODE> method frees resources used to maintain a
* connection to the source.
* If no resources are in use, <CODE>disconnect</CODE> is ignored.
* If <CODE>stop</CODE> hasn't already been called,
* calling <CODE>disconnect</CODE> implies a stop.
*
*/
public void disconnect() {
disconnectDevice();
}
/**
* Disconnect from the actual device
*/
native void disconnectDevice();
/**
* Initiate data-transfer. The <CODE>start</CODE> method must be
* called before data is available.
*(You must call <CODE>connect</CODE> before calling <CODE>start</CODE>.)
*
* @exception IOException Thrown if there are IO problems with the source
* when <CODE>start</CODE> is called.
*/
public void start() throws IOException {
/* instantiate a buffer and start the actual device, the read() method
calls start() on the device */
stream.start();
}
/**
* Stop the data-transfer.
* If the source has not been connected and started,
* <CODE>stop</CODE> does nothing.
*/
public void stop() throws IOException {
// stop the stream's thread and the device itself
stream.stop();
stopDevice();
}
/**
* Stops the actual device
*/
native void stopDevice();
/**
* Get the collection of streams that this source
* manages. The collection of streams is entirely
* content dependent. The <code>ContentDescriptor</code>
* of this <CODE>DataSource</CODE> provides the only indication of
* what streams can be available on this connection.
*
* @return The collection of streams for this source.
*/
public javax.media.protocol.PushSourceStream[] getStreams() {
// return the steams the actual device provides
return streams;
}
/**
* Get the duration of the media represented
* by this object.
* The value returned is the media's duration
* when played at the default rate.
* If the duration can't be determined (for example, the media object is presenting live
* video) <CODE>getDuration</CODE> returns <CODE>DURATION_UNKNOWN</CODE>.
*
* @return A <CODE>Time</CODE> object representing the duration or DURATION_UNKNOWN.
*/
public javax.media.Time getDuration() {
return DURATION_UNKNOWN;
}
/**
* Obtain the collection of objects that
* control the object that implements this interface.
* <p>
*
* If no controls are supported, a zero length
* array is returned.
*
* @return the collection of object controls
*/
public Object[] getControls() {
return new Object[0];
}
/**
* Obtain the object that implements the specified
* <code>Class</code> or <code>Interface</code>
* The full class or interface name must be used.
* <p>
*
* If the control is not supported then <code>null</code>
* is returned.
*
* @return the object that implements the control,
* or <code>null</code>.
*/
public Object getControl(String controlType) {
return null;
}
}
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