Package org.apache.jackrabbit.oak.commons

Class Profiler

  • All Implemented Interfaces:
    java.lang.Runnable
    public class Profiler
extends java.lang.Object
implements java.lang.Runnable
    A simple CPU profiling tool similar to java -Xrunhprof. It can be used in-process (to profile the current application) or as a standalone program (to profile a different process, or files containing full thread dumps).

    • Constructor Summary

      Constructors 
      Constructor Description
      Profiler()  

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static java.lang.instrument.Instrumentation getInstrumentation()
      Get the instrumentation object if started as an agent.
      java.lang.String getTop​(int count)
      Get the top stack traces.
      static void main​(java.lang.String... args)
      Run the command line version of the profiler.
      static void premain​(java.lang.String agentArgs, java.lang.instrument.Instrumentation inst)
      This method is called when the agent is installed.
      void run()  
      Profiler startCollecting()
      Start collecting profiling data.
      Profiler stopCollecting()
      Stop collecting.

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • interval

        public int interval

      • depth

        public int depth

      • paused

        public boolean paused

      • sumClasses

        public boolean sumClasses

      • sumMethods

        public boolean sumMethods

    • Constructor Detail

      • Profiler

        public Profiler()

    • Method Detail

      • premain

        public static void premain​(java.lang.String agentArgs,
                           java.lang.instrument.Instrumentation inst)
        This method is called when the agent is installed.
        Parameters:
        agentArgs - the agent arguments
        inst - the instrumentation object

      • getInstrumentation

        public static java.lang.instrument.Instrumentation getInstrumentation()
        Get the instrumentation object if started as an agent.
        Returns:
        the instrumentation, or null

      • main

        public static void main​(java.lang.String... args)
        Run the command line version of the profiler. The JDK (jps and jstack) need to be in the path.
        Parameters:
        args - the process id of the process - if not set the java processes are listed

      • startCollecting

        public Profiler startCollecting()
        Start collecting profiling data.
        Returns:
        this

      • stopCollecting

        public Profiler stopCollecting()
        Stop collecting.
        Returns:
        this

      • run

        public void run()
        Specified by:
        run in interface java.lang.Runnable

      • getTop

        public java.lang.String getTop​(int count)
        Get the top stack traces.
        Parameters:
        count - the maximum number of stack traces
        Returns:
        the stack traces.