ZonedDateTime通过杰克逊往返产生不平等ZonedDateTime

Question

鉴于以下单元测试：

@Test 
public void zonedDateTimeCorrectlyRestoresItself() { 

    // construct a new instance of ZonedDateTime 
    ZonedDateTime now = ZonedDateTime.now(ZoneId.of("Z")); 
    // offset = {ZoneOffset@3820} "Z" 
    // zone = {ZoneOffset@3820} "Z" 

    String converted = now.toString(); 

    // restore an instance of ZonedDateTime from String 
    ZonedDateTime restored = ZonedDateTime.parse(converted); 
    // offset = {ZoneOffset@3820} "Z" 
    // zone = {ZoneOffset@3820} "Z" 

    assertThat(now).isEqualTo(restored); // ALWAYS succeeds 
} 

@Test 
public void jacksonIncorrectlyRestoresZonedDateTime() { 

    ObjectMapper objectMapper = new ObjectMapper(); 
    objectMapper.findAndRegisterModules(); 
    objectMapper.disable(DeserializationFeature.ADJUST_DATES_TO_CONTEXT_TIME_ZONE); 

    // construct a new instance of ZonedDateTime 
    ZonedDateTime now = ZonedDateTime.now(ZoneId.of("Z")); 
    // offset = {ZoneOffset@3820} "Z" 
    // zone = {ZoneOffset@3820} "Z" 


    String converted = objectMapper.writeValueAsString(now); 

    // restore an instance of ZonedDateTime from String 
    ZonedDateTime restored = objectMapper.readValue(converted, ZonedDateTime.class); 
    // offset = {ZoneOffset@3820} "Z" 
    // zone = {ZoneOffset@3821} "UTC" 

    assertThat(now).isEqualTo(restored); // NEVER succeeds 
} 

而且这种解决方法：

@Test 
public void usingDifferentComparisonStrategySucceeds() throws Exception { 

    ObjectMapper objectMapper = new ObjectMapper(); 
    objectMapper.findAndRegisterModules(); 
    objectMapper.disable(DeserializationFeature.ADJUST_DATES_TO_CONTEXT_TIME_ZONE); 

    // construct a new instance of ZonedDateTime 
    ZonedDateTime now = ZonedDateTime.now(ZoneId.of("Z")); 
    // offset = {ZoneOffset@3820} "Z" 
    // zone = {ZoneOffset@3820} "Z" 

    String converted = objectMapper.writeValueAsString(now); 

    // restore an instance of ZonedDateTime from String 
    ZonedDateTime restored = objectMapper.readValue(converted, ZonedDateTime.class); 
    // offset = {ZoneOffset@3820} "Z" 
    // zone = {ZoneOffset@3821} "UTC" 

    // the comparison succeeds when a different comparison strategy is used 
    // checks whether the instants in time are equal, not the java objects 
    assertThat(now.isEqual(restored)).isTrue(); 
} 

我想我试图找出为什么国内杰克逊只是没有按”请拨打ZonedDateTime.parse()？就我个人而言，我认为这是杰克逊的一个缺陷，但我还没有足够的信心在没有反馈的情况下为它开启一个问题。

Answer 1

引述维基百科ISO 8601：

如果时间是UTC，没有空格的时间后直接添加Z。 Z是零UTC抵消的区域指示符。因此"09:30 UTC"表示为"09:30Z"或"0930Z"。 "14:45:15 UTC"将是"14:45:15Z"或"144515Z"。

UTC时间也被称为祖鲁时间，因为祖鲁族是Z.

北约拼音字母词

Z不是一个区。 UTC是区域，然后代表使用格式化的字符串中的Z。

千万不要使用ZoneId.of("Z")。这是不对的。