Package brave.propagation

Interface TraceContext.Injector<R>

  • Enclosing class:
    TraceContext
    public static interface TraceContext.Injector<R>
    Used to send the trace context downstream. For example, as http headers.

    For example, to put the context on an HttpURLConnection, you can do this: 

    
 // in your constructor
 injector = tracing.propagation().injector(URLConnection::setRequestProperty);

 // later in your code, reuse the function you created above to add trace headers
 HttpURLConnection connection = (HttpURLConnection) new URL("http://myserver").openConnection();
 injector.inject(span.context(), connection);

    Note: This type is safe to implement as a lambda, or use as a method reference as it is effectively a FunctionalInterface. It isn't annotated as such because the project has a minimum Java language level 6.

    Since:
    4.0

    • Method Detail

      • inject

        void inject​(TraceContext traceContext,
            R request)
        Usually calls a setter for each propagation field to send downstream.
        Parameters:
        traceContext - possibly unsampled.
        request - holds propagation fields. For example, an outgoing message or http request.