我通过为控制器实现自己的objectMapper解决了我的问题。
webservices现在必须返回一个String而不是一个对象或一个List

I've solved my problem by implementing an own objectMapper for the controller. The webservices now must return a String instead of an object or a List

private ObjectMapper objectMapper;

@PostConstruct
private void configureObjectMapper() {
    objectMapper = new ObjectMapper();
    objectMapper.setSerializationInclusion(JsonInclude.Include.NON_EMPTY);
}

@RequestMapping(...)
@ResponseBody
public String getSomething(...) {
    try {
        return objectMapper.writeValueAsString(getSomething());
    } catch (JsonProcessingException e) {
        LOG.error("Could not serialize to JSON", e);
    }
    return null;
}