Static methods and threads

[harry.clarkknovalent.com]

I have a class in a jar in my JasperServer lib which provides static methods called in expressions to process various things in a report. I did it this way to make the Java redistributable yet hide it from non-programmers. Is my class loaded once and forever by JasperServer? In which case do my static methods need to be thread-safe? And what impact would that have on performance with heavy usage? Suppose a method is called for a column in a report, i.e., every row, with the report run by >1 user at the same time. Or does JS batch the jobs and run them in sequence?

 

Or is the class loaded with each session supported in JasperServer? If that were so I wouldn't need to restart JS (Tomcat) to pick up a new jar with changes to the class.

[lucianc]

If you put a jar in the JasperServer lib folder classes from the jar would only be loaded once, by the web app class loader.

 

JasperServer runs several report simultaneously, hence your static methods need to be thread safe.

 

Regards,

Lucian