help,ImageIO

Hi,
  I'm dynamiclly creating image files through screenshot utility of
java(prog name:- Test_ScreenShot.java) and saving

them in memory sequentially(pic0.jpg,pic1.jpg....etc).Simultaneously
I'm accessing the saved files from another

independent application(Prog name:- Test_Main.java) through
piping(executing the application like this  "Java

Test_ScreenShot|Java Test_Main").The application is in infinite
loop.I'm using Version JDK 1.5


I use java ImageIO to read and write image:-
My application was running well for days.But now I'm getting sudden
exceptions.
I got an excepton while trying to save an dynamically generated image
file in the local memory using the ImageIO

class.In brief I'm getting exactly 3 types of exceptions:-



1)java.io.FileNotFoundException: pic5.jpg (Access is denied)
2)"Exception in thread "main" java.lang.NullPointerException
3)Exception in thread "main"
com.sun.image.codec.jpeg.ImageFormatException: Not a JPEG file: starts
with 0xff 0xd9


Here is the code snippent I wrote:



/* Robot robot = new Robot();
  BufferedImage image = robot.createScreenCapture(screenRect);
  // save captured image to jpg file
  ImageIO.write(image, "jpg", new File(outFileName));*/

And here is the exception I am finding (I never  found this before, I
executed the code many times )
=====================================================================================================================
1)Exception Type 1:-

java.io.FileNotFoundException: pic5.jpg (Access is denied)
        at java.io.RandomAccessFile.open(Native Method)
        at java.io.RandomAccessFile.<init>(RandomAccessFile.java:212)
        at
javax.imageio.stream.FileImageOutputStream.<init>(FileImageOutputStream.java:44)
        at
com.sun.imageio.spi.FileImageOutputStreamSpi.createOutputStreamInstance(FileImageOutputStreamSpi.java:37)
        at
javax.imageio.ImageIO.createImageOutputStream(ImageIO.java:391)
        at javax.imageio.ImageIO.write(ImageIO.java:1483)
        at Test_ScreenShot.main(Test_ScreenShot.java:112)
        at Test_Main.main(Test_Main.java:466)
        at Test_ScreenShot.main(Test_ScreenShot.java:129)

2)Exception Type 2:-
"Exception in thread "main" java.lang.NullPointerException
       at Picture.width(Picture.java:84)
       at Test_Edge_Detector.not_main(Test_Edge_Detector.java:38)
       at Test_Main.main(Test_Main.java:88)"



============================================================================================
Now I tried the following as alternative of ImageIO(from jdk 1.2)
to read image:-
FileInputStream fis = new FileInputStream(file);
      JPEGImageDecoder jpeg = JPEGCodec.createJPEGDecoder(fis);
     jpeg.decodeAsBufferedImage();
      fis.close();
But after running a long time suddenly its giving following
exceptions:-

==============================================================================================


Exception Type 3:- )


Exception in thread "main"
com.sun.image.codec.jpeg.ImageFormatException: Not a JPEG file: starts
with 0xff 0xd9
        at
sun.awt.image.codec.JPEGImageDecoderImpl.readJPEGStream(Native Method)
        at
sun.awt.image.codec.JPEGImageDecoderImpl.decodeAsBufferedImage(Unknown
Source)


Exception Type 4:- )


 javax.imageio.IIOException: Not a JPEG file: starts with 0xff 0xd9
        at
com.sun.imageio.plugins.jpeg.JPEGImageReader.readImageHeader(Native
Method)
        at
com.sun.imageio.plugins.jpeg.JPEGImageReader.readNativeHeader(Unknown
Source)
        at
com.sun.imageio.plugins.jpeg.JPEGImageReader.checkTablesOnly(Unknown
Source)
        at
com.sun.imageio.plugins.jpeg.JPEGImageReader.gotoImage(Unknown Source)
        at
com.sun.imageio.plugins.jpeg.JPEGImageReader.readHeader(Unknown Source)
        at
com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(Unknown
Source)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(Unknown
Source)
        at javax.imageio.ImageIO.read(Unknown Source)
        at javax.imageio.ImageIO.read(Unknown Source)
        at Picture.<init>(Picture.java:22)
        at Test_Edge_Detector.not_main(Test_Edge_Detector.java:37)
        at Test_Main.main(Test_Main.java:88)
Exception in thread "main" java.lang.RuntimeException: Could not open
file: pic45.jpg
        at Picture.<init>(Picture.java:27)
        at Test_Edge_Detector.not_main(Test_Edge_Detector.java:37)
        at Test_Main.main(Test_Main.java:88)





My question is:-
1)Where is the actual problem?Is it any kind of bug?
2)I'm using the concept of piping recently to execute the
application.Can it be the cause?


	When I googled I found the following informations.There is a bug in
ImageIO while trying to write image file.But
I'm not sure about that it will be relevent here :-
1)from sun's bug database:-
  http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6247985

2)from SUN Developer Forums

http://forum.java.sun.com/thread.jspa?threadID=768917&messageID=4382833

3)from Java.NET forum(here they r getting the bug while they r using
createScreenCapture() method of robot class,I am

also using that in my code)
http://forums.java.net/jive/thread.jspa?messageID=123247

4)from SUN's archieve
http://archives.java.sun.com/cgi-bin/wa?A2=ind0207&L=java-imageio-interest&D=0&P=1483

5)Here is the actual implemetation of ImageIO class.I'm getting error
at 391 no. line.
http://kickjava.com/src/javax/imageio/ImageIO.java.htm




Thanks And Regards
Subhadip