Spring MVC自定义消息转换器(可解决Long类型数据传入前端精度丢失的问题)-白红宇

方法一 jackson注解


          
      
       com.fasterxml.jackson.core
           
      
       jackson-annotations
           
      
       2.8.6
       
      
          
      
       com.fasterxml.jackson.core
           
      
       jackson-databind
           
      
       2.8.6

package com.paascloud.helper;import com.fasterxml.jackson.core.JsonGenerator;import com.fasterxml.jackson.databind.JsonSerializer;import com.fasterxml.jackson.databind.SerializerProvider;import java.io.IOException;/** * Long 类型字段序列化时转为字符串，避免js丢失精度 */public class LongJsonSerializer extends JsonSerializer
     
       {
         /**     * Serialize.     *     * @param value              the value     * @param jsonGenerator      the json generator     * @param serializerProvider the serializer provider     *     * @throws IOException the io exception     */    @Override    public void serialize(Long value, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {        String text = (value == null ? null : String.valueOf(value));        if (text != null) {            jsonGenerator.writeString(text);        }    }}

package com.paascloud.helper;import com.fasterxml.jackson.core.JsonParser;import com.fasterxml.jackson.databind.DeserializationContext;import com.fasterxml.jackson.databind.JsonDeserializer;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import java.io.IOException;/** * 将字符串转为Long */public class LongJsonDeserializer extends JsonDeserializer
     
       {
         private static final Logger logger = LoggerFactory.getLogger(LongJsonDeserializer.class);    /**     * Deserialize long.     *     * @param jsonParser             the json parser     * @param deserializationContext the deserialization context     *     * @return the long     *     */    @Override    public Long deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) {        String value = null;        try {            value = jsonParser.getText();        } catch (IOException e) {            e.printStackTrace();        }        try {            return value == null ? null : Long.parseLong(value);        } catch (NumberFormatException e) {            logger.error("解析长整形错误", e);            return null;        }    }}

@Datapublic class BaseEntity {
         @Id    @GeneratedValue(strategy = GenerationType.IDENTITY)    @JsonSerialize(using = LongJsonSerializer.class)    @JsonDeserialize(using = LongJsonDeserializer.class)    private Long id;}

发现在List中还有问题

方法二


      
          
      
       org.apache.rocketmq
           
      
       rocketmq-client
           
      
       4.1.0-incubating
       
      
          
      
       de.codecentric
           
      
       spring-boot-admin-starter-client
       
      
          
      
       org.springframework.boot
           
      
       spring-boot-starter-freemarker
       
      
          
      
       org.springframework.cloud
           
      
       spring-cloud-starter-feign

@Bean    public ObjectMapper ObjectMapper(){        SimpleModule simpleModule = new SimpleModule();        simpleModule.addSerializer(Long.class, ToStringSerializer.instance);        simpleModule.addSerializer(Long.TYPE, ToStringSerializer.instance);        ObjectMapper objectMapper = new ObjectMapper()                .registerModule(new ParameterNamesModule())                .registerModule(new Jdk8Module())                .registerModule(new JavaTimeModule())                .registerModule(simpleModule);        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);//      SerializerProvider serializerProvider = objectMapper.getSerializerProvider();//      serializerProvider.setNullValueSerializer(new JsonSerializer

小坑一个记录一下, 解决现有问题