Feign远程调用-IPage分页返回对象-序列化错误

当使用Feign调用服务IPage分页接口时，会出现序列化异常。

解决方式如下:

添加配置文件IPageDeserializer，WebDataConvertConfig

public class IPageDeserializer extends StdDeserializer<IPage> {
	protected IPageDeserializer(Class<?> vc) {
		super(vc);
	}

	/**
	 * Method that can be called to ask implementation to deserialize
	 * JSON content into the value type this serializer handles.
	 * Returned instance is to be constructed by method itself.
	 * <p>
	 * Pre-condition for this method is that the parser points to the
	 * first event that is part of value to deserializer (and which
	 * is never JSON 'null' literal, more on this below): for simple
	 * types it may be the only value; and for structured types the
	 * Object start marker or a FIELD_NAME.
	 * </p>
	 * <p>
	 * The two possible input conditions for structured types result
	 * from polymorphism via fields. In the ordinary case, Jackson
	 * calls this method when it has encountered an OBJECT_START,
	 * and the method implementation must advance to the next token to
	 * see the first field name. If the application configures
	 * polymorphism via a field, then the object looks like the following.
	 * <pre>
	 *      {
	 *          "@class": "class name",
	 *          ...
	 *      }
	 *  </pre>
	 * Jackson consumes the two tokens (the <tt>@class</tt> field name
	 * and its value) in order to learn the class and select the deserializer.
	 * Thus, the stream is pointing to the FIELD_NAME for the first field
	 * after the @class. Thus, if you want your method to work correctly
	 * both with and without polymorphism, you must begin your method with:
	 * <pre>
	 *       if (p.getCurrentToken() == JsonToken.START_OBJECT) {
	 *         p.nextToken();
	 *       }
	 *  </pre>
	 * This results in the stream pointing to the field name, so that
	 * the two conditions align.
	 * <p>
	 * Post-condition is that the parser will point to the last
	 * event that is part of deserialized value (or in case deserialization
	 * fails, event that was not recognized or usable, which may be
	 * the same event as the one it pointed to upon call).
	 * <p>
	 * Note that this method is never called for JSON null literal,
	 * and thus deserializers need (and should) not check for it.
	 *
	 * @param p    Parsed used for reading JSON content
	 * @param ctxt Context that can be used to access information about
	 *             this deserialization activity.
	 * @return Deserialized value
	 */
	@Override
	public IPage deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
		JsonNode node = p.getCodec().readTree(p);
		String s  = node.toString();
		ObjectMapper om = new ObjectMapper();
		Page page = om.readValue(s,Page.class);
		return page;
	}
}

@Configuration
public class WebDataConvertConfig extends WebMvcConfigurationSupport {


	@Override
	public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
		converters.add(mappingJackson2HttpMessageConverter());
		super.configureMessageConverters(converters);
	}

	@Bean
	public MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter() {
		MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
		ObjectMapper mapper = new ObjectMapper();
		mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);

		SimpleModule module = new SimpleModule();
		module.addDeserializer(IPage.class, new IPageDeserializer(IPage.class));
		mapper.registerModule(module);

		converter.setSupportedMediaTypes(Arrays.asList(MediaType.APPLICATION_JSON, MediaType.APPLICATION_JSON_UTF8,MediaType.APPLICATION_OCTET_STREAM));
		converter.setObjectMapper(mapper);

		return converter;
	}


}