Springmvc返回注解驱动&自定义扩展规则设置

系统管理员 2022-06-06 07:10 188阅读 0赞

**现象：**  
Springmvc返回注解驱动&自定义扩展规则设置

方法：Springmvc自带返回注解驱动

1：Springmvc自携带json转换驱动  
![这里写图片描述][SouthEast]

2：使用mvc自携带注解@ResponseBody转换将自动将对象转换为json格式返回  
![这里写图片描述][SouthEast 1]

代码：

<mvc:annotation-driven conversion-service="myConverter" validator="validator">
            <mvc:message-converters>
                <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
                    <property name="supportedMediaTypes">
                        <list>
                            <value>application/json</value>
                            <value>text/html;charset=UTF-8</value>
                        </list>
                    </property>
    
                    <property name="objectMapper">
                       <bean class="com.fasterxml.jackson.databind.ObjectMapper">
                           <property name="serializationInclusion">
                              <value type="com.fasterxml.jackson.annotation.JsonInclude.Include">NON_NULL</value>
                           </property>
                       </bean>
                  </property>
                </bean>
            </mvc:message-converters>
        </mvc:annotation-driven>

方法：自定义注解返回规则扩展设置

1：返回注解驱动设置自定义规则类  
![这里写图片描述][SouthEast 2]

2：自建立类设置规则模型加入  
![这里写图片描述][SouthEast 3]

3：新建立的规则模型(double保留两位小数)  
![这里写图片描述][SouthEast 4]

4：4使用注解返回对象将按照自定义转会规则转换为json  
![SouthEast 5][]

代码：

<mvc:annotation-driven validator="validator" >
            <mvc:argument-resolvers>
                <bean class="com.oig.argmentResolver.CurrentUserMethodArgumentResolver"></bean>
            </mvc:argument-resolvers>
            <mvc:message-converters>
                <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
                    <property name="supportedMediaTypes">
                        <list>
                            <value>application/json</value>
                            <value>text/html;charset=UTF-8</value>
                        </list>
                    </property>
                    <property name="objectMapper">
                        
                        <bean class="com.oig.utils.MyObjectMapper"></bean>
                  </property>
                </bean>
            </mvc:message-converters>
        </mvc:annotation-driven>
    
    
    /** * 新建类继承mvc自带json转换类 * 新增模型规则，设置进入对象，进行扩展 * @author Administrator */
    public class MyObjectMapper extends ObjectMapper{ 
    
        private static final long serialVersionUID = 1360761655051502549L;
    
        public MyObjectMapper(){
            //新建规则模型
            SimpleModule simpleModule = new SimpleModule();
            //设置模型
            simpleModule.addSerializer(BigDecimal.class, new BigDecimalSerilize());
            //将模型加入objectMapper对象
            registerModule(simpleModule);
            setSerializationInclusion(Include.NON_NULL);
        }
    
    }
    
    
    
    /** * 新建的jackson转换模型规则 * double保留两位小数 * @author Administrator */
    public class BigDecimalSerilize extends JsonSerializer<BigDecimal>{ 
        @Override
        public void serialize(BigDecimal value, JsonGenerator gen,
                SerializerProvider serializers) throws IOException,
                JsonProcessingException {
            gen.writeNumber(value.setScale(2, RoundingMode.HALF_UP).doubleValue());
        }
    }

[SouthEast]: /images/20220606/b83f891eaa884f5896da2e972ed72d8d.png
[SouthEast 1]: /images/20220606/898947e108554acc8edfd2bce0cab6d7.png
[SouthEast 2]: /images/20220606/f4fe379b708a4780873b9147cf256ea8.png
[SouthEast 3]: /images/20220606/784332614c8b47f3818d81e43547d320.png
[SouthEast 4]: /images/20220606/b642974ed5274a9a81813792b268b2c1.png
[SouthEast 5]: /images/20220606/6b0b2614e4814c66b73f8c265e571f52.png