org.springframework.http.converter.HttpMessageConversionException: Type definition error: [simple type, class dm.jdbc.a.a.a]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No serializer found for class dm.jdbc.a.a.a and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: com.smart.java.utils.web.control.ResponseResult["data"]->java.util.HashMap["results"]->java.util.ArrayList[0]->java.util.HashMap["LONLAT"]->com.alibaba.druid.proxy.jdbc.NClobProxyImpl["rawNClob"]->dm.jdbc.driver.DmdbNClob["connection"]->dm.jdbc.driver.DmdbConnection["dbAccess"]->dm.jdbc.a.a["b"])