Identifying lambdas in stacktrace in Java 8

Question

I am trying to profile a Java application that uses lambdas using JProfiler. I am having trouble identifying, which lambda the profiler is showing as a hotspot:

I would appreciate any help on understanding the format of the stack trace involving lambdas like "edu.indiana.soci.spidal.vectorclass.lambda$PairwiseThread_SecDrv$23"

Thank you!

Answer 1

Unfortunately, there is no direct way to identify the lambda because lambdas by nature have no name. At runtime, lambdas are currently implemented with anonymous classes. They are numbered sequentially after the $ sign with respect to the containing class.

If you turn on line number resolution in JProfiler (session settings-> profiling settings tab-> customize-> check box on the "method call recording" tab), you will see a line number on the "run" method in the hot spot back trace which should help you to find the lambda if it's the only lambda on that line.