Synchronized File Writing

Question

Hi,
I have a written a Java Program which Splits any File into two Parts. These parts can again later be rejoined to restore the Original File.
This is how Splitting Operation is performed
1. Read the SourceFile into Array of Bytes
2. Open two FileOutputStreams and Write these Bytes, half of it in each stream. This is Done using a Thread for Each stream, Obviously to save time.
3. Now i have two Files which contain Bytes for Original File.
Now in Restoring Operation:
1. Read the two Files(split using above technique) and store in Byte Arrays.
2. Open the FileOutputStream to a File and write the Above byte Arrays ONE BY ONE into this Stream.
Please note that i had to write Bytes from two byte arrays in the Order i had read it.
Which means to say that i first have to write From First Byte Array, wait for it to finish it and than write from Second Byte Array. I cannot start Threads for Writing Bcoz the Target File is Same. Also, i wouldn't know where to start writing the bytes from Second Byte Array in the target File since, the First Thread may still be performing the Write Operation from the First Byte Array
If i had been writing a C program, this would be fairly easy since i have File Pointers. I can use two programs and use fseek() operation to Know exactly where to start writing from second set of Byte Array.
Please give ur suggestion to above problem. How can i simulate File Pointer operations of C in Java.
I hope i am Clear in describing the Problem. If not, then please let me know......and Thnx for u Patience

Answer 1

try not to cross post.
http://forum.java.sun.com/thread.jsp?forum=4&thread=165965&start=0&range=30#501577