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Line based access with RandomAccessFile  RSS feed

 
Satya Maheshwari
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Hi
Is there some sort of abstraction available over RandomAccessFile that let me jump(seek) to a specified line number in the file.
Any help appreciated!
 
Andrey Kozhanov
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I believe you have to write your own class. I would extend RandomAccessFile and implement CharSequence, and then use this class in Pattern and Matcher to find EOL sequence.
 
Stephan van Hulst
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This isn't very useful, because the point of a RandomAccessFile is to provide, well, random access. If you need to find the number of lines in a file, whether you do this with a Pattern or otherwise, you still end up reading the entire file up to the point you want to jump to.

Simply wrap the file in a Scanner or a BufferedReader or something.
 
Rob Camick
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Its only useful if the size of each line is a fixed length. Then in this case you can randomly read line.
 
It is sorta covered in the JavaRanch Style Guide.
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