Package io.quarkus.arc

Interface ClientProxy

public interface ClientProxy
Represents a client proxy - a contextual reference to a bean with a normal scope.

Client proxy delegates all method invocations to a target contextual instance. Note that only method invocations are delegated. So a field of a normal scoped bean should never be read or written in order to avoid working with non-contextual or stale data.

In general, client proxies allow for:

  • Lazy instantiation - the instance is created once a method is invoked upon the proxy.
  • Ability to inject a bean with "narrower" scope to a bean with "wider" scope; i.e. you can inject a @RequestScoped bean into an @ApplicationScoped bean.
  • Circular dependencies in the dependency graph. Having circular dependencies is often an indication that a redesign should be considered, but sometimes it’s inevitable.
  • In rare cases it’s practical to destroy the beans manually. A direct injected reference would lead to a stale bean instance.

  • Method Details

    • arc_contextualInstance

      Object arc_contextualInstance()
      Returns:
      the contextual instance

    • arc_bean

      InjectableBean<?> arc_bean()
      Returns:
      the bean

    • unwrap

      static <T> T unwrap(T obj)
      Attempts to unwrap the object if it represents a client proxy.

      This method should only be used with caution. If you unwrap a client proxy then certain key functionality will not work as expected.

      Type Parameters:
      T -
      Parameters:
      obj -
      Returns:
      the contextual instance if the object represents a client proxy, the object otherwise