Java Performance measurement

Question

I am doing some Java performance comparison between my classes, and wondering if there is some sort of Java Performance Framework to make writing performance measurement cod

Answer 1

OpenJDK guys have developed a benchmarking tool called JMH:

http://openjdk.java.net/projects/code-tools/jmh/

This provides quite an easy to setup framework, and there is a couple of samples showing how to use that.

http://hg.openjdk.java.net/code-tools/jmh/file/tip/jmh-samples/src/main/java/org/openjdk/jmh/samples/

Nothing can prevent you from writing the benchmark wrong, but they did a great job at eliminating the non-obvious mistakes (such as false sharing between threads, preventing dead code elimination etc).