java - Jackson 序列化和反序列化 DateTime From/To W​​CF DateTime

Question

我使用 Jackson 来序列化和反序列化对象。我有 .NET WCF DateTime JSON 格式和 Time Zone 。并且 jackson 无法将 JSON 反序列化为对象。我找到了一些解决方案，但是有没有嵌入的 Jackson 或建议的解决方案如何做到这一点？

示例日期:

"/日期(12345678989+0000)/"

"/日期(12345678989-0000)/"

也可以看看:
How to parse .net DateTime received as json string into java's Date object

Answer 1

以 .NET 生成的格式处理日期时间的 JavaScriptSerializer形式/Date(number of ticks)/您需要实现自定义反序列化器。要了解什么是“滴答声”，让我们看看 documentation :

Date object, represented in JSON as "/Date(number of ticks)/". The number of ticks is a positive or negative long value that indicates the number of ticks (milliseconds) that have elapsed since midnight 01 January, 1970 UTC.

The maximum supported date value is MaxValue (12/31/9999 11:59:59 PM) and the minimum supported date value is MinValue (1/1/0001 12:00:00 AM).

我假设，在您的情况下，您也提供了一个偏移量，就像在示例中一样。

使用 Java 8 Time包和以上知识，我们可以实现自定义反序列化器如下加上示例用法:

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;

import java.io.IOException;
import java.time.Instant;
import java.time.OffsetDateTime;
import java.time.ZoneOffset;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class JsonPathApp {

    public static void main(String[] args) throws Exception {
        String inputJson = "{\"date\":\"/Date(1583001930882+0100)/\"}";

        ObjectMapper mapper = new ObjectMapper();
        Epoch epoch = mapper.readValue(inputJson, Epoch.class);
        System.out.println(epoch.getDate());
    }
}

class Epoch {

    @JsonDeserialize(using = JavaScriptDateDeserializer.class)
    private OffsetDateTime date;

    public OffsetDateTime getDate() {
        return date;
    }

    public void setDate(OffsetDateTime date) {
        this.date = date;
    }
}

class JavaScriptDateDeserializer extends JsonDeserializer<OffsetDateTime> {

    private final Pattern JAVASCRIPT_DATE = Pattern.compile("/Date\\((-?\\d+)([+-]\\d+)\\)/");

    @Override
    public OffsetDateTime deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
        String value = p.getValueAsString();
        Matcher matcher = JAVASCRIPT_DATE.matcher(value);
        if (matcher.matches()) {
            String epoch = matcher.group(1);
            String offset = matcher.group(2);

            Instant instant = Instant.ofEpochMilli(Long.parseLong(epoch));

            return OffsetDateTime.ofInstant(instant, ZoneOffset.of(offset));
        }

        return null;
    }
}

上面的代码打印:

2020-02-29T19:45:30.882+01:00

序列化器可能如下所示:

class JavaScriptDateSerializer extends JsonSerializer<OffsetDateTime> {

    @Override
    public void serialize(OffsetDateTime value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
        StringBuilder builder = new StringBuilder(32);
        builder.append("/Date(");
        builder.append(value.toInstant().toEpochMilli());
        if (!value.getOffset().equals(ZoneOffset.UTC)) {
            builder.append(value.getOffset().toString());
        }
        builder.append(")/");

        gen.writeString(builder.toString());
    }
}

如果您总是在 UTC 中发送/接收日期，则需要正确处理时区你可以跳过这部分。

也可以看看:

WCF and JSON Date format

JavaScript's Date

Unix epoch time to Java Date object

javascriptserializer date format issue

Good (Date)Times with Json.NET

C# DateTime.Ticks equivalent in Java