Appending data to the beginning of a file

How do you write data to the first line of a file without overwriting the data which is already present?
Data before:
888826759 100011021
888826767 100011026
888826916 100011024
888826916 100011023
888826940 100011029
888826940 100011028
888857389 100011020
888871480 100011029
What I want data to look like after:
ABC
888826759 100011021
888826767 100011026
888826916 100011024
888826916 100011023
888826940 100011029
888826940 100011028
888857389 100011020
888871480 100011029
I'm trying this, but it doesn't work as it overwrites the first piece of data in the file
file.seek(0);
file.writeBytes("ABC");so that the output is:
ABC826759 100011021
Edited by: drakester on Oct 12, 2007 10:59 AM

You might be able to write the file into one of the Collection Lists that maintain order (like LinkedList, but there are others), add the first line, and then rewrite the file from the list. You might also find the Collections methods reverse and rotate could be useful if you add the data at the end of the list.
You could also create an array and fill the 2nd through last elements with the file lines, insert your data as the first element, then write the file from the array.
Ther are a number of variations on the above approaches.

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Attachments:
how to save data acquisition in excel.jpg ‏51 KB
data acquisition_excel.jpg ‏20 KB

On the Write To Spreadsheet File function, there is a boolean input to append to file. Set that to TRUE.
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[How to Upload and Download Files in a Web Dynpro for Java Application|http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/9076a593-2b08-2d10-2890-9a7078246ec4?QuickLink=index&overridelayout=true]
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