code: protected void logMultipleMappingFailedForField(String facebookFieldName,
        FieldWithAnnotation<Facebook> fieldWithAnnotation, String json) {
      if (!MAPPER_LOGGER.isTraceEnabled()) {
        return;
      }
  
      Field field = fieldWithAnnotation.getField();
  
      MAPPER_LOGGER.trace(
        "Could not map '{}' to {}. {}, but continuing on because '{}"
            + "' is mapped to multiple fields in {}. JSON is {}",
        facebookFieldName, field.getDeclaringClass().getSimpleName(), field.getName(), facebookFieldName,
        field.getDeclaringClass().getSimpleName(), json);
    }
docs: Dumps out a log message when one of a multiple-mapped Facebook field name JSON-to-Java mapping operation fails.
  
  @param facebookFieldName
  The Facebook field name.
  @param fieldWithAnnotation
  The Java field to map to and its annotation.
  @param json
  The JSON that failed to map to the Java field.