Question

I’m looking for the least impacting method to read a few different log files. By ‘least impacting’ I mean the read wont affect log rotation, wont cause undue I/O activity, etc. I’m looking to accomplish this with Java…

Google afforded me the following little snippit of code:

FileStream fs = new FileStream('C:\foo.txt', FileMode.Open,FileAccess.Read, FileShare.ReadWrite); 

This should be failry trivial to implement, but, I’m none too sure of my Java ‘cut and paste’ abilities and would like to know if there is a much better way to do this. The big picture here is to troll some apache and tomcat logs looking for a few key entries based on application activity and take some action based on the entry. Anyway, any tips? Thank you!

Answer 1

Pick one from here

🙂

I haven’t try them all but there are some useful comments from Jon Skeet on how not to do it.

My bet will be for the nio one.

 FileInputStream stream = new FileInputStream(new File(path));   try {     FileChannel fc = stream.getChannel();     MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, fc.size());     /* Instead of using default, pass in a decoder. */     return CharSet.defaultCharset().decode(bb).toString();   }   finally {     stream.close();   } 

See details in that question.