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How do I create, read and write binary records to a file?

Posted on 2006-11-01
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Last Modified: 2010-03-31
Hello,
This question is kinda basic, but it is something I cannot find any reference to do. I want to be able to create a record of a fixed size. Two Long integers stored in a record / class of some sort. Then I need to be able to write this data record by record to a binary file. I also need to know how to read this binary data back out of the file.

Please provide code examples.

Worth 500 points.

Rick
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Question by:richardsimnett
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by:CEHJ
ID: 17849462
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by:sciuriware
sciuriware earned 800 total points
ID: 17849465
Use RandomAccessFile:

  RandomAccessFile f = new RandomAccessFile(new File("myfile"), "rw");
  long[] k = new long[2];

  k[0] = f.readLong();
  k[1] = f.readLong();
 
;JOOP!
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Expert Comment

by:sciuriware
ID: 17849482
To write the same 'k' after 1200 bytes:

    f.seek(1200L);
    f.writeLong(k[0]);
    f.writeLong(k[1]);

;JOOP!
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Accepted Solution

by:
objects earned 1200 total points
ID: 17853072
agree with sciuriware, you'll find a good intro/example of using RAF here:

http://java.sun.com/developer/TechTips/2000/tt0509.html
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by:richardsimnett
ID: 17881432
Thanks!

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by:sciuriware
ID: 17881469
:)
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