io.opentracing

Interface ScopeManager

public interface ScopeManager

The ScopeManager interface abstracts both the activation of Span instances via activate(Span) and access to an active Span via activeSpan().

See Also:

Scope, Tracer.scopeManager()

Method Summary

Modifier and Type	Method and Description
Scope	activate(Span span) Set the specified Span as the active instance for the current context (usually a thread).
Span	activeSpan() Return the currently active Span.

Method Detail

activate

Scope activate(Span span)

Set the specified Span as the active instance for the current context (usually a thread).

The returned Scope represents the active state for the span. Once its active period is due, Scope.close() ought to be called. To ease this operation, Scope supports try-with-resources. Observe the span will not be automatically finished when Scope.close() is called.

The corresponding Span can be accessed at any time through activeSpan().

Usage:

     Span span = tracer.buildSpan("...").start();
     try (Scope scope = tracer.scopeManager().activate(span)) {
         span.setTag("...", "...");
         ...
     } catch (Exception e) {
         span.log(...);
     } finally {
         // Optionally finish the Span if the operation it represents
         // is logically completed at this point.
         span.finish();
     }
 

Parameters:

span - the Span that should become the activeSpan()

Returns:

a Scope instance to control the end of the active period for the Span. It is a programming error to neglect to call Scope.close() on the returned instance.

activeSpan

Span activeSpan()

Return the currently active Span.

Because both #active() and activeSpan() reference the current active state, they both will be either null or non-null.

Returns:

the active span, or null if none could be found.