目录
- 1 问题
- 2 实现
1 问题
返回给前端的数据，如果数据库的字段没有数据，给返回的是null
要变成这个，全局都变成这样
2 实现
springboot返回给页面的json数据中，如果有数据为null，则返回空字符串。
springboot默认使用jackson解析返回json数据。
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;/** * 处理 jackson 返回的null值 * */@Configurationpublic class JacksonConfig {@Bean@Primary@ConditionalOnMissingBean(ObjectMapper.class)public ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder) {ObjectMapper objectMapper = builder.createXmlMapper(false).build();objectMapper.getSerializerProvider().setNullValueSerializer(new JsonSerializer<Object>() {@Overridepublic void serialize(Object o, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {jsonGenerator.writeString("");}});return objectMapper;}}只需要加上以上的配置就可以了