无法从字符串反序列化LocalDateTime类型的值

问题描述

我有以下DTO和Entity：

public class PaymentDto {

    private String provider;

    private Duration timeDifferenceDate;

    public PaymentDto() {
        // Empty for framework
    }

    public PaymentDto(Payment payment) {
        this.provider = payment.getProvider();
        this.setRegistrationDate(payment.getRegistrationDate());
    }

    public Duration getRegistrationDate() {
        return timeDifferenceDate;
    }

    public void setRegistrationDate(LocalDateTime registrationDate) {
        LocalDateTime Now = LocalDateTime.Now();
        Duration duration = Duration.between(Now,registrationDate);
        this.timeDifferenceDate = duration;
    }

}

public class Payment {

    private LocalDateTime registrationDate;

    public Payment() {
        // Empty for framework
    }

但是当它从Payment转换为PaymentDto时，我遇到了JSON解码的问题，特别是从LocalDateTime到Duration的转换时。有想法吗？

    @Override
    public List<PaymentDto> readAll() {
        return this.paymentPersistence.readAll().stream()
                .map(PaymentDto::new).collect(Collectors.toList());
    }

org.springframework.core.codec.DecodingException: JSON decoding error: Cannot deserialize value of type `java.time.LocalDateTime` from String "PT-1.015005S": Failed to deserialize java.time.LocalDateTime: (java.time.format.DateTimeParseException) Text 'PT-1.015005S' Could not be parsed at index 0; nested exception is com.fasterxml.jackson.databind.exc.InvalidFormatException: Cannot deserialize value of type `java.time.LocalDateTime` from String "PT-1.015005S": Failed to deserialize java.time.LocalDateTime: (java.time.format.DateTimeParseException) Text 'PT-1.015005S' Could not be parsed at index 0
 at [Source: UNKNowN; line: -1,column: -1] (through reference chain: com.user.rest.dtos.PaymentDto["registrationDate"])

    at org.springframework.http.codec.json.AbstractJackson2Decoder.processException(AbstractJackson2Decoder.java:215)
    Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
    |_ checkpoint ⇢ Body from GET http://localhost:61072/payments [DefaultClientResponse]
Stack trace:
        at org.springframework.http.codec.json.AbstractJackson2Decoder.processException(AbstractJackson2Decoder.java:215)

谢谢。 ;）

解决方法

LocalDateTime无法转换为Duration，反之亦然。除了Serializable（当然还有Object）之外，在他们的层次结构中没有其他共同之处。

替换

private LocalDateTime registrationDate;

使用

private Duration registrationDate;

或创建类型为Duration的新实例变量。

,

作为@Arvind Kumar Avinash mentioned above，您需要在设置器Duration中提供适当的类型PaymentDto::setRegistrationDate。

如果您从返回LocalDateTime字段的实体中填充DTO，也应该修改“转换”构造函数。另外，在计算持续时间时，应将registrationDate放在第一位，以避免“负”持续时间（时间越早越早）。

public PaymentDto(Payment payment) {
    this.provider = payment.getProvider();
    this.setRegistrationDate(Duration.between(
        payment.getRegistrationDate(),// older "start" date should go first
        LocalDateTime.now()
    ));
}

public void setRegistrationDate(Duration timeDifference) 
    this.timeDifferenceDate = timeDifference;
}