core/src/com/google/inject/internal/Errors.java
static <T> T checkNotNull(T reference, String name) {
    if (reference != null) {
      return reference;
    }

    NullPointerException npe = new NullPointerException(name);
    throw new ConfigurationException(ImmutableSet.of(new Message(npe.toString(), npe)));
  }
static <T> T checkNotNull(T reference, String name) {
    if (reference != null) {
      return reference;
    }

    NullPointerException npe = new NullPointerException(name);
    throw new ConfigurationException(ImmutableSet.of(new Message(npe.toString(), npe)));
  }
Throws a ConfigurationException with an NullPointerExceptions as the cause if the given
reference is {@code null}.