Interface IdGenerator<T>

Type Parameters:
T - the type of identifier produced
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface IdGenerator<T>
Contract for generating Request identifiers of a particular type (for example, sequential Long values, random UUIDs, etc.)

Useful for incorporating request data in nonlocal deployment environments (e.g. a tracing header like X-Amzn-Trace-Id).

Implementations may or may not guarantee uniqueness, ordering, or repeatability of generated identifiers. Callers should not assume any such guarantees unless documented by the implementation.

Standard threadsafe implementations can be acquired via these factory methods:

Author:
Mark Allen

  • Method Details

    • generateId

      @NonNull T generateId(@NonNull Request request)
      Generates an identifier for the given Request.

      Implementations may choose different strategies (sequential, random, host-based, etc.) and are not required to guarantee uniqueness unless explicitly documented.

      Implementations may choose to incorporate request data (e.g. a tracing header like X-Amzn-Trace-Id).

      Parameters:
      request - the request for which an identifier is being generated
      Returns:
      the generated identifier (never null)

    • defaultInstance

      static @NonNull IdGenerator<String> defaultInstance()
      Acquires a threadsafe IdGenerator with a best-effort local IP prefix.

      This method is guaranteed to return a new instance.

      Returns:
      an IdGenerator with default settings

    • fromPrefix

      static @NonNull IdGenerator<String> fromPrefix(@NonNull String prefix)
      Acquires a threadsafe IdGenerator with the given prefix.

      This method is guaranteed to return a new instance.

      Parameters:
      prefix - a string to prepend to the generated numeric ID
      Returns:
      an IdGenerator configured with the given prefix