springMvc 配置键值对为空替换为 '' jackson数据绑定配置键值对为null替换为 ''

淡淡的烟草味﹌ 2023-07-10 14:18 38阅读 0赞

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 org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.Primary;
    import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
    
    import java.io.IOException;
    
    /**
     * @Description: jackson数据绑定配置键值对为空替换为 ''
    **/
    @Configuration
    public class JacksonConfig {
        @Bean
        @Primary
        @ConditionalOnMissingBean(ObjectMapper.class)
        public ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder) {
            ObjectMapper objectMapper = builder.createXmlMapper(false).build();
            objectMapper.getSerializerProvider().setNullValueSerializer(new JsonSerializer<Object>() {
                @Override
                public void serialize(Object o, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
                    jsonGenerator.writeString("");
                }
            });
            return objectMapper;
        }
    }

如果你是用的xml，配置如下

自定义一个类用来处理为NULL的字段：

public class TransferJsonSerializer extends JsonSerializer<Object> {  
        @Override  
        public void serialize(Object value, JsonGenerator jgen, SerializerProvider provider)  
                throws IOException, JsonProcessingException {  
            jgen.writeString("");
        }  
    }