How to put a breakpoint on every line in the code using JVMTI?

According to the documentation, I have to use

jvmtiError
SetBreakpoint(jvmtiEnv* env,
            jmethodID method,
            jlocation location)

Basically, I need to iterate over each class, then get each method of each class, and then put a breakpoint on every location. But I want to exclude non-project classes. How to do that? Thank you!