How to multiple objects stored in a file.

Hi,
there is a file on which multiple object have been written.
Now while reading it back, is it necessary to read the objects in the same sequence in which they were written or i can randomly read any object?
thanx
deepak saini

If that's really a concern, you could write the objects to separate files.
Alternatively, if you're really keen, look at RandomAccessFile. You'd have to build InputStream and OutputStream bridges to be able to use ObjectInputStream and ObjectOutputStream. You'd probably want to use BufferedInputStream and BufferedOutputStream in there too.
You'd start by writing a long of value zero the file. Then use a new ObjectOuptutStream for each object (rembering to close each one), retaining a List of offsets into the file where the objects start. Then you'd write the List itself using another ObjectOutputStream. Finally you position back to the beginning of the file, and write the offset of the List as a long, overwriting the long zero value.
The reading side is left for as exercise for the reader.
This would allow you to read directly any object given its index into the List.
This is only worthwhile if you're talking about lots of objects.
And, as I said, only if you're keen :)
Sylvia.

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Hi,
there is a file on which multiple object have been written.
Now while reading it back, is it necessary to read the objects in the same sequence in which they were written or i can randomly read any object?
thanx
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