Need to parse and analyse tomcat logs

Hello all,
I have been assinged a projetc where I am to parse and analyse tomcat logs archive of 6 months and search for occurence of a String pattern.

Can someone help me to take the initial steps?
I am looking for either an opensource code project for the same or some code examples.

Please help.

-Viidhya

Well if you're using Java it should be too difficult to read in each log file and search based on a String pattern/Regular Expression. Many might argue that a language like PERL would be more suited for the task though...

In Java you can easily use the File and related I/O APIs to read the file into a buffer and the look at the Pattern and String apis for the regular expression pattern matching.

Thanks Martijn.
Well Pseudo of what I am supposed to do is :
1. Open each zip folder in archive folder.
2. If there is a file starting with 'Flare', open the file.
3. Search for occurence of a String in the file, and if exists, write the entry to an Excel/Csv file.
4. Do the same for all the zips in the folder.

Is this possible to be done using Java?

Absolutely yes.

There are even many tutorials and resources here on Javaranch to help you get started, see Here to begin.

I would look into using splunk. In a nutshell it compresses logs and allows you to query them and run ad hoc reports against them. It is free for even a fair amount of logs. Their site has lots of videos showing how it works. I installed and had it analyzing my logs in about 10 minutes. It is a very cool tool!

Recently I saw another product I can't recall the name of that let us look at our logs for the past 4 years by hour that was quite interesting...