FileDocCategorySizeDatePackage
DataSource.javaAPI DocJMF 2.1.1e5123Mon May 12 12:21:22 BST 2003com.ibm.media.protocol.device

DataSource

public class DataSource extends PushDataSource
This is a DataSource that reprents an audio capture device

Fields Summary
DevicePushSourceStream
stream
The actual stream
DevicePushSourceStream[]
streams
The streams array
Constructors Summary
public DataSource()
A no-argument constructor required by pre 1.1 implementations so that this class can be instantiated by calling Class.newInstance.

	com.sun.media.JMFSecurityManager.loadLibrary("jmdevice");
    
	super();
Methods Summary
public voidconnect()
Open a connection to the source described by the MediaLocator.

The connect method initiates communication with the source.

exception
IOException Thrown if there are IO problems when connect is called.

	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();
native voidconnectDevice()
Connect to the actual device

public voiddisconnect()
Close the connection to the source described by the locator.


The disconnect method frees resources used to maintain a
connection to the source.
If no resources are in use, disconnect is ignored.
If stop hasn't already been called,
calling disconnect implies a stop.
	disconnectDevice();
    
native voiddisconnectDevice()
Disconnect from the actual device
public java.lang.StringgetContentType()
Get a string that describes the content-type of the media
that the source is providing.


It is an error to call getContentType if the source is
not connected.
return
The name that describes the media content.
	// tempotary implementation
	return "raw";
    
public java.lang.ObjectgetControl(java.lang.String controlType)
Obtain the object that implements the specified
Class or Interface
The full class or interface name must be used.



If the control is not supported then null
is returned.
return
the object that implements the control,
or null.
	return null;
    
public java.lang.Object[]getControls()
Obtain the collection of objects that
control the object that implements this interface.



If no controls are supported, a zero length
array is returned.
return
the collection of object controls
	return new Object[0];
    
public javax.media.TimegetDuration()
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) getDuration returns DURATION_UNKNOWN.
return
A Time object representing the duration or DURATION_UNKNOWN.
	return DURATION_UNKNOWN;
    
public javax.media.protocol.PushSourceStream[]getStreams()
Get the collection of streams that this source
manages. The collection of streams is entirely
content dependent. The ContentDescriptor
of this DataSource provides the only indication of
what streams can be available on this connection.
return
The collection of streams for this source.
	// return the steams the actual device provides
	return streams;
    
public voidstart()
Initiate data-transfer. The start method must be
called before data is available.
(You must call connect before calling start.)
exception
IOException Thrown if there are IO problems with the source
when start is called.
	/* instantiate a buffer and start the actual device, the read() method
	   calls start() on the device */
	stream.start();
    
public voidstop()
Stop the data-transfer.
If the source has not been connected and started,
stop does nothing.

	// stop the stream's thread and the device itself 
	stream.stop();
	stopDevice();
    
native voidstopDevice()
Stops the actual device