Static calls and performance

Question

Is there anyone with knowledge fo the internal workings of the JVM?
I was wondering, is a static call in Java automatically synchronized? I can't find a resource with a satisfying answer, so I thought I try it here. I was having some performance problems reading from a file, So I decided to read the file once while strating up the application. But it's a web application, so I'm using servlets. You have to be careful not to use synchronized methods within the dopost or doget of a servlet, because all requests will be handled by the same thread initially. But referencing a class using a static method also gave me performance problems. Simply doing a static call for a String for times instead of one time increased the performance of the application by 100%. Does anyone have the theoretical foundation behind this behaviour?
regards,
Jeroen.

Answer 1

static methods are not synchronized unless you use the key word "synchronized". Using "synchronized" with a static function blocks on any other static synchronized methods from a different thread, however it will allow access via a synchronized non-static method. Check out "Taming Java Threads" by allen holub for more info.
if you can read the file in the init() method and cache it then you wouldn't have to read it every time in the dopost(), doget() methods.
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