Injection point metadata

There is lots of useful metadata information that is present on an injection point, which is represented in the javax.enterprise.inject.spi.InjectionPoint interface. Weld provides an implementation of InjectionPoint with @Dependent scope and @Default qualifier for us to retrieve the metadata.

The injection point provides the following functions:

When we have an @Dependent scoped bean, there are occasions when it needs to retrieve metadata about the injection point to be properly constructed. A typical example of this requirement is with a logger:

class LoggerFactory {
  @Produces
  Logger createLogger(InjectionPoint point) {
    return Logger.getLogger(point.getMember().getDeclaringClass().getName());
  }
}

Injecting a logger with the name set to that of the class is then:

@Inject
Logger log;

Writing that simple producer has saved us time in not needing to specifically retrieve the class name to set it on a logger in every class we want to use it.