retrofit-converters/jaxb/src/main/java/retrofit2/converter/jaxb/JaxbConverterFactory.java
@SuppressWarnings("ConstantConditions") // Guarding public API nullability.
  public static JaxbConverterFactory create(JAXBContext context) {
    if (context == null) throw new NullPointerException("context == null");
    return new JaxbConverterFactory(context);
  }
@SuppressWarnings("ConstantConditions") // Guarding public API nullability.
  public static JaxbConverterFactory create(JAXBContext context) {
    if (context == null) throw new NullPointerException("context == null");
    return new JaxbConverterFactory(context);
  }
Create an instance using {@code context} for conversion.