Interface Propagator.Getter<C>

  • Type Parameters:
    C - carrier of propagation fields, such as an http request.
    Enclosing interface:
    Propagator

    public static interface Propagator.Getter<C>
    Interface that allows a TextMapPropagator to read propagated fields from a carrier.

    Getter is stateless and allows to be saved as a constant to avoid runtime allocations.

    • Method Detail

      • get

        @Nullable
        String get​(C carrier,
                   String key)
        Returns the first value of the given propagation key or returns null.
        Parameters:
        carrier - carrier of propagation fields, such as an http request.
        key - the key of the field.
        Returns:
        the first value of the given propagation key or returns null.