There isn't defined set of rules to improve the performance of the application. Few generic comments:
1. Define what is the expected response time of your application.
2. Once you have defined 1 check if you have good enough hardware to support it.
3. Both 1 and 2 are satisfactory, yet application is slow, then check for any network latency issues.
4. 1, 2 and 3 seems to be doing okay, then instrument your application to determine where exactly the time is spent. Is it the database, is it the middle tier code, is it something else?
5. Once you have determined the bottleneck, then work to resolve it.
I understood, you are asking about profiling tools in java. JProfile using this profiler tool we can estimate the usage of memory, the usage of particular instructions, or frequency and duration of function calls. The most common use of profiling information is to aid program optimization.
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