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CloneableCapturePushBufferDataSource.javaAPI DocJMF 2.1.1e6164Mon May 12 12:21:04 BST 2003com.ibm.media.protocol

CloneableCapturePushBufferDataSource.java

/*
 * @(#)CloneableCapturePushBufferDataSource.java	1.2 02/08/21
 *
 * Copyright (c) 1996-2002 Sun Microsystems, Inc.  All rights reserved.
 */

package com.ibm.media.protocol;

import java.io.*;

import javax.media.*;
import javax.media.protocol.*;


/**
 * This is a utility class for creating clones of PushBufferDataSource. 
 * THe class reflects the functionality of a PushBufferDataSource and provides
 * a getClone() method for generating clones. The generated clone will be of
 * type PushBufferDataSource and its streams will generate a trasferData() call
 * each time the PushBufferDataSource's streams call transferData().
 * This class also implements the CaptureDevice interface.
 */  
public class CloneableCapturePushBufferDataSource extends PushBufferDataSource 
  implements SourceCloneable, CaptureDevice {
  
  private SuperCloneableDataSource superClass;
  
  /**
   * Constructor
   *
   * @param source  the source to be cloned
   */
  public CloneableCapturePushBufferDataSource(PushBufferDataSource source) {
    
    superClass = new SuperCloneableDataSource(source);
  }
  
  /**
   * 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 PushBufferStream[] getStreams() {
    
    if (superClass.streams == null) {
      superClass.streams = new PushBufferStream[superClass.streamsAdapters.length];
      for (int i = 0; i < superClass.streamsAdapters.length; i++)
	superClass.streams[i] = (PushBufferStream)superClass.streamsAdapters[i].getAdapter();
    }
    
    return (PushBufferStream[])superClass.streams;
  }
  
  
  /**
   * Clone the original datasource, returning an object of the type
   * <code>PushDataSource</code> or <code>PushBufferDataSource</code>. 
   * If the original data source was a
   * PullDataSource, then this will be a PushDataSource which pushes at
   * the same rate at which the CloneableDataSource is being pulled.
   * @return a slave DataSource for this DataSource.
   */
  public DataSource createClone() {
    
    return superClass.createClone();
  }
  
  /**
   * 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() {
    
    return superClass.getContentType();
  }
  
  /**
   * 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 {
    
    superClass.connect();
  }
  
  /**
   * 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() {
    
    superClass.disconnect();
  }
  
  /**
   * 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 {
    
    superClass.start(); 
  }
  
  /**
   * Stop the data-transfer.
   * If the source has not been connected and started,
   * <CODE>stop</CODE> does nothing.
   */
  public void stop() throws IOException {
    
    superClass.stop();
  }
  
  /**
   * 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 superClass.getControls();
  }
  
  /**
   * 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 superClass.getControl(controlType);
  }
  
  /**
   * 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 Time getDuration() {
    
    return superClass.getDuration();
  }
  
  /**
   * Return the <code>CaptureDeviceInfo</code> object that describes 
   * this device.
   * @return The <code>CaptureDeviceInfo</code> object that describes 
   * this device.
   */
  public javax.media.CaptureDeviceInfo getCaptureDeviceInfo() {
    
    return ((CaptureDevice)superClass.input).getCaptureDeviceInfo();
  }

  /**
   * Returns an array of <code>FormatControl</code> objects.  Each of
   * them can be used to set and get the format of each capture stream. 
   * This method can be used before connect to set and get the
   * capture formats. 
   * @return an array for FormatControls.
   */
  public javax.media.control.FormatControl[] getFormatControls() {
    
    return ((CaptureDevice)superClass.input).getFormatControls();
  }
}