Checking to see existance of a file before creating one.

Posted on 2001-08-14
Last Modified: 2010-03-31

I am creating a servlet where in the Init() method, I am creating a file. however, I need to modify it and am not sure how to do it.

when the servlet is loaded, and the init method called, I need to first check to see if there is an existing file before before creating the file. This is to ensure that I do not overwrite the data from a day before. This is the code that I have currently to create a new file. Could you please modify it to include the logic to check to see if this particular file exists in the given directory before creating it. Thanks,

     //Now to set up the Performance log File initially when the servlet is loaded
          outputFile = new File("/u/iscdev/Performance/Performance.txt");
          out = new RandomAccessFile(outputFile, "rw");
     catch( e)
Question by:gvijay1
LVL 19

Accepted Solution

Jim Cakalic earned 100 total points
ID: 6384698
Use the File.exists method. You can do this even before attempting to open. Something like this, for example:

outputFile = new File("/u/iscdev/Performance/Performance.txt");
if (outputFile.exists() == false) {
    // file doesn't exist
    out = new RandomAccessFile(outputFile, "rw");
} else {
    // do whatever

Best regards,
Jim Cakalic


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Expert Comment

by:Jim Cakalic
ID: 9072415
Recommendation: points to jim_cakalic
LVL 20

Expert Comment

ID: 9330386
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