context-propagation 1.1.0 · io.micrometer.context

This package contains abstractions and implementations for context propagation.

io.micrometer.context.ThreadLocalAccessor and io.micrometer.context.ContextAccessor allow applications and frameworks to plug in support for java.lang.ThreadLocal and other Map-like types of context such as the Project Reactor Contexts.
io.micrometer.context.ContextRegistry provides a static instance with global access to all known accessors that should be registered on startup.
io.micrometer.context.ContextSnapshot uses the ContextRegistry and is used to capture context values, and then propagate them from one type of context to another or from one thread to another.

Interface Summary

Modifier and Type	Interface and Description
public interface	ContextAccessor< type of context for reading READ, type of context for writing WRITE> Contract to assist with access to an external, map-like context, such as the Project Reactor `Context`, including the ability to read values from it a `Map` and to write values to it from a `Map`.
public interface	ContextSnapshot Holds values extracted from `ThreadLocal` and other types of context and exposes methods to propagate those values.
public interface	ContextSnapshotFactory Factory for creating `ContextSnapshot` objects and restoring `ThreadLocal` values using a context object for which a `ContextAccessor` exists in the `ContextRegistry`.
public interface	ThreadLocalAccessor<V> Contract to assist with setting and clearing a `ThreadLocal`.

Modifier and Type	Annotation and Description
pack-priv @interface	NonNullApi Declares all method parameters and return values within a package as non-nullable via JSR-305 meta-annotations to indicate nullability in Java.
pack-priv @interface	NonNullFields Declares all fields within a package as non-nullable via JSR-305 meta-annotations to indicate nullability in Java.
pack-priv @interface	Nullable Annotation to declare that a method parameter, return value, or field can be `null` under some circumstance.

Modifier and Type	Class and Description
public class	ContextExecutorService<EXECUTOR extends ExecutorService> Wraps an `ExecutorService` in order to capture context via `ContextSnapshot` when a task is submitted, and propagate context to the task when it is executed.
public class	ContextRegistry Registry that provides access to, instances of `ContextAccessor` and `ThreadLocalAccessor`.
public class	ContextScheduledExecutorService Wraps a `ScheduledExecutorService` in order to capture context via `ContextSnapshot` when a task is submitted, and propagate context to the task when it is executed.
pack-priv class	DefaultContextSnapshot Default implementation of `ContextSnapshot`.
pack-priv class	DefaultContextSnapshotFactory Default implementation of `ContextSnapshotFactory`.