SpringBoot ResponseBody返回值處理的實(shí)現(xiàn)

更新時間：2020年11月06日 11:46:47 作者：小安灬

這篇文章主要介紹了SpringBoot ResponseBody返回值處理的實(shí)現(xiàn)，文中通過示例代碼介紹的非常詳細(xì)，對大家的學(xué)習(xí)或者工作具有一定的參考學(xué)習(xí)價值，需要的朋友們下面隨著小編來一起學(xué)習(xí)學(xué)習(xí)吧

1. SpringBoot ResponseBody 返回值中null值處理

@PostMapping(path = "/test", produces = MediaType.APPLICATION_JSON_VALUE)
public Object test() {
 JSONObject jsonObject = new JSONObject();
 jsonObject.put("test","test");
 jsonObject.put("testnull",null);
 ApiResponseVo apiResponseVo = new ApiResponseVo();
 apiResponseVo.setData(jsonObject );
 apiResponseVo.setStatus(0);
 return apiResponseVo;
}

接口返回 (想實(shí)現(xiàn)將testnull也進(jìn)行返回<null展示null還是0還是"" 可自定義>) :

{
  "data": {
    "test": "test"
  },
  "status": 0
}

import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
@Configuration
public class fastJsonConfig extends WebMvcConfigurationSupport {
 @Override
 public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
 FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter();
 FastJsonConfig config = new FastJsonConfig();
 config.setSerializerFeatures(
  // 保留 Map 空的字段
  SerializerFeature.WriteMapNullValue,
  // 將 String 類型的 null 轉(zhuǎn)成""
//        SerializerFeature.WriteNullStringAsEmpty,
        // 將 Number 類型的 null 轉(zhuǎn)成 0
//        SerializerFeature.WriteNullNumberAsZero,
        // 將 List 類型的 null 轉(zhuǎn)成 []
//        SerializerFeature.WriteNullListAsEmpty,
        // 將 Boolean 類型的 null 轉(zhuǎn)成 false
//        SerializerFeature.WriteNullBooleanAsFalse,
  // 避免循環(huán)引用
  SerializerFeature.DisableCircularReferenceDetect
 );
 converter.setFastJsonConfig(config);
 converter.setDefaultCharset(Charset.forName("UTF-8"));
 List<MediaType> mediaTypeList = new ArrayList<>();
 // 解決中文亂碼問題，相當(dāng)于在 Controller 上的 @RequestMapping 中加了個屬性 produces = "application/json"
 mediaTypeList.add(MediaType.APPLICATION_JSON);
 converter.setSupportedMediaTypes(mediaTypeList);
 converters.add(converter);
 }
}

2. 攔截responsebody轉(zhuǎn)json,對數(shù)據(jù)進(jìn)行二次處理 (字典轉(zhuǎn)換做案例)

2.1> 設(shè)置攔截器

import java.nio.charset.StandardCharsets;
import java.util.List;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
import com.fintell.dp3.manager.interceptor.LogInterceptor;
@Configuration
public class WebMvcConfiguration implements WebMvcConfigurer {
 @Override
 public void addInterceptors(InterceptorRegistry registry) {
 // 自定義攔截器，添加攔截路徑和排除攔截路徑
 registry.addInterceptor(getLogInterceptor()).addPathPatterns("/**");
 }
 @Bean
 public LogInterceptor getLogInterceptor() {
 return new LogInterceptor();
 }
 /**
 * 修改StringHttpMessageConverter默認(rèn)配置 & Json 默認(rèn)序列化方式 (改這個方法)
 */
 @Override
 public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
   //創(chuàng)建fastJson消息轉(zhuǎn)換器
   FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
   //創(chuàng)建配置類
   FastJsonConfig fastJsonConfig = new FastJsonConfig();
   //修改配置返回內(nèi)容的過濾
   fastJsonConfig.setSerializerFeatures(
       SerializerFeature.DisableCircularReferenceDetect,
       SerializerFeature.WriteMapNullValue,
       SerializerFeature.WriteNullStringAsEmpty
   );
   fastConverter.setFastJsonConfig(fastJsonConfig);
   //將fastjson添加到視圖消息轉(zhuǎn)換器列表內(nèi)
   converters.add(fastConverter);
 }
}

2.2> 字典注解類

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface Dict {
 String type(); 
}

2.3> 序列化類

import java.io.IOException;
import java.lang.reflect.Field;
import org.apache.commons.lang3.StringUtils;
import org.springframework.context.annotation.Configuration;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializerProvider;
import lombok.extern.slf4j.Slf4j;
@Slf4j
@Configuration
public class DictJsonSerializer extends JsonSerializer<Object> {
 @Override
  public void serialize(Object dictVal, JsonGenerator generator, SerializerProvider provider) throws IOException {
   ObjectMapper objectMapper = new ObjectMapper();
    String currentName = generator.getOutputContext().getCurrentName();
    try {
      // 1> 獲取字段
      Field field = generator.getCurrentValue().getClass().getDeclaredField(currentName);
      // 2> 獲取字典注解
      Dict dict = field.getDeclaredAnnotation(Dict.class);
      // 3> 判斷是否添加了字典注解
      if(dict == null) {
       objectMapper.writeValue(generator, dictVal);
       return;
      }
      // 4> 獲取注解的type值
      String type = dict.type();
      // **************** 以下依據(jù)實(shí)際業(yè)務(wù)處理即可 ********************
      // 5> 獲取到字段的值
      String val = dictVal == null ? "" : dictVal.toString();
      String dictValName = "";
      if(!StringUtils.isEmpty(val)) {
        // 6> 這里可以依據(jù)type做不同的處理邏輯
       dictValName = "通過自己的方法,依據(jù)val獲取到對應(yīng)的字典值";
      }
      // 7> 將字段改寫為{"code":"code","name":"name"}格式
      objectMapper.writeValue(generator, BaseEnum.builder().code(dictVal).name(dictValName.toString()).build());
    } catch (NoSuchFieldException e) {
     log.error(e);
    }
  }
}

2.4> 字典注解使用

@SuppressWarnings("serial")
@Builder
@Getter
@Setter
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class BizRuleDto implements Serializable{
  // 指定使用哪種序列化
  @JsonSerialize(using = DictJsonSerializer.class)
  // 指定字典 (將被轉(zhuǎn)換為{"code":"content","name":"contentname"}格式)
  @Dict(type = "content")
 private String content;
}

3. 其它補(bǔ)充 (從容器中獲取某個實(shí)例) : 如 DictJsonSerializer 需要通過service查詢數(shù)據(jù)庫獲取字典

@Slf4j
public class DictJsonSerializer extends JsonSerializer<Object> {
  // service
 private static ProductProxy productProxy;
 static {
 productProxy = SpringUtils.getBean(ProductProxy.class);
 }
  @Override
  public void serialize(Object dictVal, JsonGenerator generator, SerializerProvider provider) throws IOException {
  }
}

SpringUtils

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
@Component
public class SpringUtils implements ApplicationContextAware {
 private static ApplicationContext ctx;
 /**
 * 獲取bean
 */
 @SuppressWarnings("unchecked")
 public static <T> T getBean(String id) {
 return (T) ctx.getBean(id);
 }
 /**
 * 按類型獲取bean
 */
 public static <T> T getBean(Class<T> clazz) {
 return ctx.getBean(clazz);
 }
 @Override
 public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
 ctx = applicationContext;
 }
}

到此這篇關(guān)于SpringBoot ResponseBody返回值處理的實(shí)現(xiàn)的文章就介紹到這了,更多相關(guān)SpringBoot ResponseBody返回值內(nèi)容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持腳本之家！

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