com.facebook.litho

Class ThreadTracingRunnable

java.lang.Object

com.facebook.litho.ThreadTracingRunnable

All Implemented Interfaces:

java.lang.Runnable

public abstract class ThreadTracingRunnable
extends java.lang.Object
implements java.lang.Runnable

ThreadTracingRunnable tries to help debugging crashes happening across threads showing the stacktrace of the crash origin which scheduled this runnable.

A stacktrace, together with the origin thread name, is going to be "saved" at the time this class is instantiated and appended as "cause" to whatever is thrown from the run() method.

To use this class, just extends it instead of implementing Runnable. Then just implement tracedRun(ThreadTracingRunnable).

If the runnable is created ahead of time and used somewhere else later, a new, more relevant, stacktrace can be created calling resetTrace().

If you need to chain another Runnable from your run method, you can pass the Throwable parameter from tracedRun(ThreadTracingRunnable) to the constructor tracedRun(ThreadTracingRunnable). Therefore, the crash can now be tracked across boundaries of multiple threads.

Constructor Summary

Constructors

Constructor and Description
ThreadTracingRunnable()
ThreadTracingRunnable(ThreadTracingRunnable prevTracingRunnable) If you are chaining multiple Runnable together that are going to schedule each other within their run() method, use this constructor to track their stacktraces across threads.

Method Summary

Modifier and Type	Method and Description
void	resetTrace() Reset the stacktrace of this Runnable to this point.
void	run()
abstract void	tracedRun(ThreadTracingRunnable prevTracingRunnable) Implement here your Runnable.run() code.

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadTracingRunnable

public ThreadTracingRunnable()

ThreadTracingRunnable

public ThreadTracingRunnable(ThreadTracingRunnable prevTracingRunnable)

If you are chaining multiple Runnable together that are going to schedule each other within their run() method, use this constructor to track their stacktraces across threads. The required parameter here is the argument coming from tracedRun(ThreadTracingRunnable).

Method Detail

tracedRun

public abstract void tracedRun(ThreadTracingRunnable prevTracingRunnable)

Implement here your Runnable.run() code.

Parameters:

prevTracingRunnable - If this ThreadTracingRunnable schedule another ThreadTracingRunnable to another thread, pass this parameter to the new ThreadTracingRunnable class with ThreadTracingRunnable(ThreadTracingRunnable).

resetTrace

public void resetTrace()

Reset the stacktrace of this Runnable to this point. To be called right before the runnable is scheduled to another thread, in case it was instantiated ahead of time with a different code flow.

run

public final void run()

Specified by:

run in interface java.lang.Runnable