java - Spring Json 响应中的时区问题

Question

我在 JSON 输出中显示日期时遇到问题。在代码中我使用 java.util.Date ，其值为 2019-03-07 但在 JSON 中我得到 2019-03-06 23:00:00 。我认为问题出在时区，但我也不在数据库和代码中使用时区。

我试图用它来修复它

@JsonFormat(pattern = "yyyy-MM-dd hh:mm:ss", timezone="UTC")

和

@JsonFormat(pattern = "yyyy-MM-dd hh:mm:ss", timezone="欧洲/华沙")

第一个没有帮助，第二个有帮助，但我不接受这个解决方案。

我的 Controller 的一部分:

return new ThisDay(
    sysoperMgr.getToday(),
    new Date()
);

这是我返回的对象。

@Getter
@Setter
public class ThisDay {

    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    Date dataZamkniecia;

    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    Date dataSystemowa;

    public BiezacaDoba(Date dataZamkniecia, Date dataSystemowa) {
        this.dataZamkniecia = dataZamkniecia;  // cdate = 2019-03-07T00:00:00.000+0100
        this.dataSystemowa = dataSystemowa; // cdate = 2019-03-27T16:08:12.343+0100
    }
}

此函数获取日期:

public Date getToday() {

    Timestamp timestamp = sysoperDao.getDataOstatniejZamknietejDoby(); // cdate = 2019-03-06T00:00:00.000+0100
    java.util.Date lastDay = new java.sql.Date(misc.roundTimestamp(timestamp).getTime()); // cdate = 2019-03-06T00:00:00.000+0100
    java.util.Date thisDay = misc.incrementDate(ostatniaDoba, Increment.DAILY, 1); // cdate = 2019-03-07T00:00:00.000+0100
    return thisDay;
}

Json 结果:

{
  "dataZamkniecia":"2019-03-06 23:00:00",
  "dataSystemowa": "2019-03-27 15:12:15"
}

如何让 JSON 始终以本地时区显示日期？

Answer 1

Date 是过时的类，自 Java 8 发布 java.time 包以来不应该使用，或者我们可以使用 Joda-Time 。您正在将日期从 Timestamp 转换为 java.sql.Date，然后再转换为 java.util.Date。这是非常不安全的，请参见下面的示例:

import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;

import java.time.LocalDate;
import java.time.ZoneId;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class JsonApp {

    public static void main(String[] args) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        mapper.enable(SerializationFeature.INDENT_OUTPUT);

        // Java time precise dates
        LocalDate localDateOpened = LocalDate.of(2019, 03, 07);
        LocalDate localDateClosed = localDateOpened.plusDays(20);

        ZoneId utc = ZoneId.of("UTC");
        Date opened = Date.from(localDateOpened.atStartOfDay(utc).toInstant());
        Date closed = Date.from(localDateClosed.atStartOfDay(utc).toInstant());

        System.out.println("Dates generated from java.time.*");
        System.out.println(mapper.writeValueAsString(new ThisDay(opened, closed)));

        // Calculate dates with default timezone
        Calendar calendar = Calendar.getInstance();
        opened = calendar.getTime();
        calendar.add(Calendar.DAY_OF_MONTH, 20);
        closed = calendar.getTime();

        System.out.println("Dates generated from Calendar");
        System.out.println(mapper.writeValueAsString(new ThisDay(opened, closed)));

        // Calculate dates with UTC timezone
        calendar = Calendar.getInstance();
        calendar.setTimeZone(TimeZone.getTimeZone(utc));
        calendar.set(Calendar.MILLISECOND, 0); // Recompute

        opened = calendar.getTime();
        calendar.add(Calendar.DAY_OF_MONTH, 20);
        closed = calendar.getTime();

        System.out.println("Dates generated from UTC Calendar");
        System.out.println(mapper.writeValueAsString(new ThisDay(opened, closed)));
    }
}

class ThisDay {

    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private Date opened;

    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private Date closed;

    public ThisDay(Date opened, Date closed) {
        this.opened = opened;
        this.closed = closed;
    }

    public Date getOpened() {
        return opened;
    }

    public void setOpened(Date opened) {
        this.opened = opened;
    }

    public Date getClosed() {
        return closed;
    }

    public void setClosed(Date closed) {
        this.closed = closed;
    }
}

上面的代码打印:

Dates generated from java.time.*
{
  "opened" : "2019-03-07 00:00:00",
  "closed" : "2019-03-27 00:00:00"
}
Dates generated from Calendar
{
  "opened" : "2019-03-27 23:45:12",
  "closed" : "2019-04-16 22:45:12"
}
Dates generated from UTC Calendar
{
  "opened" : "2019-03-28 00:45:12",
  "closed" : "2019-04-17 00:45:12"
}

请注意，第二个和第三个开放日期相差一小时。我手动将日历时区设置为 UTC 并强制重新计算值，将毫秒设置为 0:

calendar.setTimeZone(TimeZone.getTimeZone(utc));
calendar.set(Calendar.MILLISECOND, 0); // Recompute

这就是为什么 Date 已经过时并且应该使用 java.time 包的原因。如果您不想显示时间，只需将日期格式更改为 @JsonFormat(pattern = "yyyy-MM-dd")。

另请参阅:

• Spring Boot Jackson date and timestamp Format