SpringBoot全局处理LocalDateTime返回格式和Long类型序列化

import com.fasterxml.jackson.databind.ser.std.StdScalarSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.core.JsonGenerator;
import java.io.IOException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
 
public class LocalDateTimeSerializer extends StdScalarSerializer<LocalDateTime> {
 
    private static final long serialVersionUID = 1L;
    private final DateTimeFormatter formatter;
 
    protected LocalDateTimeSerializer(DateTimeFormatter formatter) {
        super(LocalDateTime.class);
        this.formatter = formatter;
    }
 
    @Override
    public void serialize(LocalDateTime value, JsonGenerator gen, SerializerProvider provider) throws IOException {
        gen.writeString(formatter.format(value));
    }
 
    // 自定义LongSerializer
    public static class LongSerializer extends StdScalarSerializer<Long> {
 
        private static final long serialVersionUID = 1L;
 
        protected LongSerializer() {
            super(Long.class);
        }
 
        @Override
        public void serialize(Long value, JsonGenerator gen, SerializerProvider provider) throws IOException {
            if (value == null) {
                gen.writeString("");
            } else {
                gen.writeNumber(value);
            }
        }
    }
}

在Spring Boot中，你可以在配置类中添加如下配置来使用这个自定义的序列化器：

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.ser.std.StdScalarSerializers;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.time.format.DateTimeFormatter;
 
@Configuration
public class JacksonConfig {
 
    @Bean
    public ObjectMapper objectMapper() {
        ObjectMapper mapper = new ObjectMapper();
        // 禁用默认的序列化特性
        mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        // 自定义LocalDateTime的序列化格式
        mapper.serializerByType(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        // 自定义Long类型序列化器
        mapper.serializerProvider().addValueSerializer(Long.class, new LocalDateTimeSerial