Problem Converting Byte Array to Datasource For JMF

[shahiz]

basically im having null pointer exception

//read an inputstream
is = new DataInputStream (new FileInputStream ("test.mpg") );
loadBytes(is);

//pass it as a datasource for the player
public void loadBytes(Input Stream is){
DataSource ds=new DataSource(is);
player = Manager.createP layer(ds);

//datasource class
import java.io.*;
import java.nio.ByteBu ffer;
import javax.media.*;
import javax.media.pro tocol.*;

public class DataSource extends PullDataSource {
private InputStream is;
private byte [] bytes;

/** Creates new MediaViewerData Source */
public DataSource(Inpu tStream is) {
super();
this.is = is;
try{
int byteCount = is.available();
bytes = new byte [byteCount];
is.read(bytes);
}
catch (Exception e){
System.out.prin tln(e);
}
}

public PullSourceStrea m [] getStreams() {

PullSourceStrea m [] streams = new PullSourceStrea m [1];
InputSourceStre am iss = new InputSourceStre am(new ByteArrayInputS tream(bytes), new FileTypeDescrip tor(ContentDesc riptor.RAW));
streams[0] = iss;
return streams;

}

public void connect() {}

public void disconnect() {}

public String getContentType( ) {
return new String(FileType Descriptor.MPEG );
}

public MediaLocator getLocator() {
return null;
}

public void initCheck() {}

public void setLocator(Medi aLocator source) {}

public void start() {}

public void stop() {}

public Object getControl(Stri ng s){
return null;
}


public Object [] getControls(){
return null;
}

public Time getDuration(){
return null;
}

}

//inputsourcestre am class
import java.io.InputSt ream;
import java.io.IOExcep tion;
import java.nio.ByteBu ffer;

import javax.media.pro tocol.ContentDe scriptor;
import javax.media.pro tocol.PullSourc eStream;
import javax.media.pro tocol.Seekable;
import javax.media.pro tocol.SourceStr eam;

/**
* Build a source stream out of an input stream.
*
* @see DataSource
* @see SourceStream
* @see java.io.InputSt ream
*
* @version %I%, %E%.
*
*/
public
class InputSourceStre am implements PullSourceStrea m, Seekable {

protected InputStream stream;
protected boolean eosReached;
ContentDescript or contentType;
protected ByteBuffer inputBuffer;
/**
* Construct an <CODE>InputSour ceStream</CODE> from an input stream.
*
* @param s The input stream to build the source stream from.
* @param type The content-type of the source stream.
*/
public InputSourceStre am(InputStream s, ContentDescript or type) {
stream = s;
eosReached = false;
contentType = type;

}

/**
* Get the content type for this stream.
*
* @return content descriptor for the stream.
*/
public ContentDescript or getContentDescr iptor() {
return contentType;
}

/**
* Obtain the content length
*
* @return content length for this stream.
*/
public long getContentLengt h() {
return SourceStream.LE NGTH_UNKNOWN;
}

/**
* Query if the next read will block.
*
* @return true if a read will block.
*/
public boolean willReadBlock() {
if( eosReached == true) {
return true;
} else {
try {
return stream.availabl e() == 0;
} catch (IOException e) {
return true;
}
}
}

/**
* Read a buffer of data.
*
* @param buffer The buffer to read data into.
* @param offset The offset into the buffer for reading.
* @param length The number of bytes to read.
* @return The number of bytes read or -1 indicating end-of-stream.
*/
//this where the problem lies
//unable to read the stream into the
// inputBuffer thus giving me the error
public int read(byte[] buffer, int offset, int length) throws IOException { int bytesRead = stream.read(buf fer, offset, length); if( bytesRead == -1) { eosReached = true;
}
inputBuffer.get (buffer,offset, length);
return bytesRead;
}

/**
* Turn the stream off.
*
* @exception IOException Thrown if there is a problem closing the stream.
*/
public void close() throws IOException {
stream.close();
}
/**
* Return if the end of stream has been reached.
* @return true if the end of the stream has been reached.
*/
// $jdr: This is a bug. Need to figure out
// the "correct" way to determine, before a read
// is done, if we're at EOS.
public boolean endOfStream() {
return eosReached;
}

/**
* Returns an zero length array because no controls
* are supported.
*
* @return a zero length <code>Object</code> array.
*/
public Object[] getControls() {
return new Object[0];
}

/**
* Returns <code>null</code> because no controls are implemented.
*
* @return <code>null</code>.
*/
public Object getControl(Stri ng controlName) {
return null;
}
public long seek(long where) {
try {
inputBuffer.pos ition((int)(whe re));
return where;
}
catch (IllegalArgumen tException E) {
return this.tell(); // staying at the current position
}
}
public long tell() {
return inputBuffer.pos ition();
}

public void SeekableStream( ByteBuffer byteBuffer) {
inputBuffer = byteBuffer;
this.seek((long )(0)); // set the ByteBuffer to to beginning
}
public boolean isRandomAccess( ) {
// TODO Auto-generated method stub
return false;
}
}

please take a look and i'll appreciate any assistance
thank you

[r035198x]

1.) Please use code tags when posting code.
2.) Read the exception trace again. Which line in your code is reported for that exception?

[shahiz]

im sorry about not using code tags
was my first post

this is error from the program

LoadInputStream.loadBytes() - Creating DataSource (InputStream)
LoadInputStream.loadBytes() - Creating Player
LoadInputStream.loadBytes() - Adding Controller Listener
LoadInputStream.loadBytes() - realizing player
Exception in thread "JMF thread: com.sun.media.amovie.AMController@1855af5[ com.
sun.media.amovie.AMController@1855af5 ] ( realizeThread)" java.lang.NullPointerException
        at InputSourceStream.tell(InputSourceStream.java:146)
        at com.sun.media.amovie.AMController.seek(AMController.java:361)
        at com.sun.media.amovie.ActiveMovie.seek(ActiveMovie.java:279)
        at com.sun.media.amovie.ActiveMovie.<init>(ActiveMovie.java:66)
        at com.sun.media.amovie.AMController.createActiveMovie(AMController.java:324)
        at com.sun.media.amovie.AMController.doRealize(AMController.java:416)
        at com.sun.media.RealizeWorkThread.process(BasicController.java:1400)
        at com.sun.media.StateTransitionWorkThread.run(BasicController.java:1339

it seem that the read method in InputSourceStre am class does not read the stream

public int read(byte[] buffer, int offset, int length) throws IOException {	
int bytesRead = stream.read(buffer, offset, length);
if( bytesRead == -1) {
eosReached = true;
}
inputBuffer.get(buffer,offset,length);
return bytesRead;
}

this is the null pointer exception error

public long tell() {
return inputBuffer.position();
}