Package brave.propagation

Class CurrentTraceContext.Default

java.lang.Object

brave.propagation.CurrentTraceContext

brave.propagation.ThreadLocalCurrentTraceContext

brave.propagation.CurrentTraceContext.Default

Enclosing class:

CurrentTraceContext

public static final class CurrentTraceContext.Default
extends ThreadLocalCurrentTraceContext

Default implementation which is backed by a static thread local.

A static thread local ensures we have one context per thread, as opposed to one per thread- tracer. This means all tracer instances will be able to see any tracer's contexts.

The trade-off of this (instance-based reference) vs the reverse: trace contexts are not separated by tracer by default. For example, to make a trace invisible to another tracer, you have to use a non-default implementation.

Sometimes people make different instances of the tracer just to change configuration like the local service name. If we used a thread-instance approach, none of these would be able to see eachother's scopes. This would break Tracing.currentTracer() scope visibility in a way few would want to debug. It might be phrased as "MySQL always starts a new trace and I don't know why."

If you want a different behavior, use a different subtype of CurrentTraceContext, possibly your own, or raise an issue and explain what your use case is.

Nested Class Summary

Nested classes/interfaces inherited from class brave.propagation.ThreadLocalCurrentTraceContext

ThreadLocalCurrentTraceContext.Builder

Nested classes/interfaces inherited from class brave.propagation.CurrentTraceContext

CurrentTraceContext.Default, CurrentTraceContext.Scope, CurrentTraceContext.ScopeDecorator

Method Summary

Modifier and Type	Method	Description
static CurrentTraceContext	create()	Uses a non-inheritable static thread local
static CurrentTraceContext	inheritable()	Uses an inheritable static thread local which allows arbitrary calls to Thread.start() to automatically inherit this context.

Methods inherited from class brave.propagation.ThreadLocalCurrentTraceContext

clear, get, newBuilder, newScope

Methods inherited from class brave.propagation.CurrentTraceContext

decorateScope, executor, executorService, maybeScope, wrap, wrap

Methods inherited from class java.lang.Object

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

Method Details

create

public static CurrentTraceContext create()

Uses a non-inheritable static thread local

inheritable

public static CurrentTraceContext inheritable()

Uses an inheritable static thread local which allows arbitrary calls to Thread.start() to automatically inherit this context. This feature is available as it is was the default in Brave 3, because some users couldn't control threads in their applications.

This can be a problem in scenarios such as thread pool expansion, leading to data being recorded in the wrong span, or spans with the wrong parent. If you are impacted by this, switch to create().