Class ThreadTracer

java.lang.Object
edu.berkeley.cs.jqf.instrument.tracing.ThreadTracer
public class ThreadTracer extends Object
This class is responsible for tracing for an instruction stream generated by a single thread in the application.

A ThreadTracer instance processes low-level bytecode instructions instrumented by JQF/Janala and converts them into appropriate TraceEvent instances, which are then emitted to be processed by the guidance-provided callback.

Author:
Rohan Padhye

  • Field Details

    • tracee

      protected final Thread tracee

    • entryPointClass

      protected final String entryPointClass

    • entryPointMethod

      protected final String entryPointMethod

    • callback

      protected final Consumer<TraceEvent> callback

    • callBackException

      protected RuntimeException callBackException

  • Constructor Details

    • ThreadTracer

      protected ThreadTracer(Thread tracee, String entryPoint, Consumer<TraceEvent> callback)
      Creates a new tracer that will process instructions executed by an application thread.
      Parameters:
      tracee - the thread to trace
      entryPoint - the outermost method call to trace (formatted as fq-class#method)
      callback - the callback to invoke whenever a trace event is emitted

  • Method Details

    • spawn

      protected static ThreadTracer spawn(Thread thread)
      Spawns a thread tracer for the given thread.
      Parameters:
      thread - the thread to trace
      Returns:
      a tracer for the given thread

    • emit

      protected final void emit(TraceEvent e)
      Emits a trace event to be consumed by the registered callback.
      Parameters:
      e - the event to emit

    • consume

      protected final void consume(Instruction ins)
      Handles tracing of a single bytecode instruction.
      Parameters:
      ins - the instruction to process