该错误消息说，没有适当
HttpMessageConverter的请求类型找到，因此只需添加
MappingJackson2HttpMessageConverter与
MediaType以
RestTemplate
MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter(); coverter.setSupportedMediaTypes(Arrays.asList(MediaType.TEXT_PLAIN, MediaType.APPLICATION_JSON); restTemplate.getMessageConverters().add(0, converter)
