core/src/com/google/inject/internal/AbstractBindingBuilder.java
protected BindingImpl<T> annotatedWithInternal(Class<? extends Annotation> annotationType) {
    checkNotNull(annotationType, "annotationType");
    checkNotAnnotated();
    return setBinding(
        binding.withKey(Key.get(this.binding.getKey().getTypeLiteral(), annotationType)));
  }
protected BindingImpl<T> annotatedWithInternal(Class<? extends Annotation> annotationType) {
    checkNotNull(annotationType, "annotationType");
    checkNotAnnotated();
    return setBinding(
        binding.withKey(Key.get(this.binding.getKey().getTypeLiteral(), annotationType)));
  }
Sets the binding to a copy with the specified annotation on the bound key