springboot 日期格式化全局LocalDateTime

在Spring Boot中，要实现全局的LocalDateTime格式化，你可以创建一个自定义的JsonSerializer和JsonDeserializer，然后将它们注册到Spring的Jackson配置中。以下是具体步骤和示例代码：

1. 创建自定义的JsonSerializer和JsonDeserializer：

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.SerializationContext;
import com.fasterxml.jackson.databind.JsonSerializer;
import java.io.IOException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
 
public class LocalDateTimeSerializer extends JsonSerializer<LocalDateTime> {
    private static final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
 
    @Override
    public void serialize(LocalDateTime value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
        gen.writeString(formatter.format(value));
    }
}
 
public class LocalDateTimeDeserializer extends JsonDeserializer<LocalDateTime> {
    private static final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
 
    @Override
    public LocalDateTime deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
        JsonNode node = p.getCodec().readTree(p);
        return LocalDateTime.parse(node.textValue(), formatter);
    }
}

2. 注册自定义的序列化器和反序列化器：

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
 
@Configuration
public class JacksonConfig {
 
    @Bean
    public ObjectMapper objectMapper() {
        ObjectMapper mapper = new ObjectMapper();
        SimpleModule module = new SimpleModule();
        module.addSerializer(LocalDateTime.class, new LocalDateTimeSerializer());
        module.addDeserializer(LocalDateTime.class, new LocalDateTimeDeserializer());
        mapper.registerModule(module);
        return mapper;
    }
}

这样配置后，Spring Boot项目中的LocalDateTime对象在序列化和反序列化时将使用你定义的格式化方式。