使用JacksonMapper反序列化Java 8 LocalDateTime [英] Deserialize Java 8 LocalDateTime with JacksonMapper
问题描述
我已经在SO中阅读了几个问题，关于 java.time.LocalDateTime 和JSON属性之间的序列化和反序列化，但我似乎无法使其正常工作。
我已设法配置我的Spring Boot应用程序以我想要的格式返回日期（ YYY-MM-dd HH：mm ）但是我在接受JSON中这种格式的值时遇到了问题。
这些是我到目前为止所做的所有事情：
为 jsr310 添加了maven依赖项：
<依赖性>
< groupId> com.fasterxml.jackson.datatype< / groupId>
< artifactId> jackson-datatype-jsr310< / artifactId>
< / dependency>
我的主要课程中指定的 jsr310 ：
@EntityScan（basePackageClasses = {App.class，Jsr310JpaConverters.class}）
禁用序列化作为 application.properties中的时间戳：
spring.jackson.serialization.write_dates_as_timestamps = false
这是我的日期时间实体映射：
@Column（name =start_date）
@DateTimeFormat（ iso = DateTimeFormat.ISO.TIME）
@JsonFormat（pattern =YYYY-MM-dd HH：mm）
private LocalDateTime startDate;
在我的数据库中，我将此日期存储为TIMESTAMP，格式如下： 2016-12-01T23：00：00 + 00:00 。
如果我通过我的控制器访问此实体，它将返回JSON正确的startDate格式。当我尝试发布它并反序列化时，使用 YYYY-MM-dd HH：mm 格式，我得到以下异常：
{
timestamp：2016-10-30T14：22：25.285 + 0000，
status：400，
错误：错误请求，
异常：org.springframework.http.converter.HttpMessageNotReadableException，
消息：无法读取文档：无法反序列化值从字符串\2017-01-01 20：00\输入java.time.LocalDateTime：无法解析文本'2017-01-01 20:00'：无法从TemporalAccessor获取LocalDateTime：{MonthOfYear = 1 ，WeekBasedYear [WeekFields [SUNDAY，1]] = 2017，DayOfMonth = 1}，ISO解析为类型java.time.format.Parsed \ n的20:00在[来源：java.io.PushbackInputStream@679a734d;行： 6，柱：]（通过参考链：com.gigsterous.api.model.Event [\ startDate\]）16;嵌套的异常是com.fasterxml.jackson.databind.exc.InvalidFormatException：不能反序列化值类型ja来自String \2017-01-01 20：00\的va.time.LocalDateTime：无法解析文本'2017-01-01 20:00'：无法从TemporalAccessor获取LocalDateTime：{MonthOfYear = 1， WeekBasedYear [WeekFields [SUNDAY，1]] = 2017，DayOfMonth = 1}，ISO解析为类型java.time.format.Parsed \ n的20:00在[来源：java.io.PushbackInputStream@679a734d; line：6，column：16]（通过引用链：com.gigsterous.api.model.Event [\startDate \]），
path：/ api / events
}
我知道有很多关于这个主题的答案，但是关注他们并尝试了几个小时没有帮助我弄清楚我做错了什么，所以如果有人可以向我指出我错过了什么，我会很高兴。感谢您对此有任何意见！
<编辑：这些是该过程中涉及的所有类：
存储库：
@Repository
公共接口EventRepository扩展PagingAndSortingRepository<事件，长> {
}
'p>控制器：
@RequestMapping（方法= RequestMethod.POST，消耗= MediaType.APPLICATION_JSON_VALUE）
public ResponseEntity< Event> createEvent（@RequestBody Event event）{
返回新的ResponseEntity<>（eventRepo.save（event），HttpSt atus.CREATED）;
}
我的JSON请求payalod：
{
name：Test，
startDate：2017-01-01 20:00
}
事件：
@Entity
@Table（name =events）
@Getter
@Setter
public class Event {
@Id
@GeneratedValue（strategy = GenerationType.AUTO）
@Column（name =event_id）
private long id;
@Column（name =name）
private String name;
@Column（名称= 起始日期）
@DateTimeFormat（异= DateTimeFormat.ISO.TIME）
@JsonFormat（图案=YYYY-MM-DD HH：MM ）
private LocalDateTime startDate;
}
你的日期时间传递不是iso本地日期时间格式。
更改为
@Column（name =start_date）
@DateTimeFormat（iso = DateTimeFormatter.ISO_LOCAL_DATE_TIME）
@JsonFormat（pattern =YYYY-MM-dd HH：mm）
private LocalDateTime startDate ;
并以2011-12-03T10：15：30格式传递日期字符串。
但如果您仍想传递自定义格式，请使用指定正确的格式化程序。
更改为
@Column（名称= 起始日期）
@DateTimeFormat（异= DateTimeFormatter.ofPattern（YYYY-MM -dd HH：mm））
@JsonFormat（pattern =YYYY-MM-dd HH：mm）
private LocalDateTime startDate;
我认为你的问题是@DateTimeFormat根本没有效果。由于杰克逊正在进行解除分类，并且它对弹簧注释没有任何了解，因此我没有看到Spring在反序列化上下文中扫描此注释。
或者，您可以尝试设置注册java时间模块时格式化。
LocalDateTimeDeserializer localDateTimeDeserializer = new LocalDateTimeDeserializer（DateTimeFormatter.ofPattern（yyyy-MM-dd HH：毫米））;
module.addDeserializer（LocalDateTime.class，localDateTimeDeserializer）;
这是deseralizer的测试用例，工作正常。可能是试图摆脱DateTimeFormat标注完全的。
@RunWith（JUnit4.class）
公共类JacksonLocalDateTimeTest {
私有ObjectMapper objectMapper;
@Before
public void init（）{
JavaTimeModule module = new JavaTimeModule（）;
LocalDateTimeDeserializer localDateTimeDeserializer = new LocalDateTimeDeserializer（DateTimeFormatter.ofPattern（yyyy-MM-dd HH：mm））;
module.addDeserializer（LocalDateTime.class，localDateTimeDeserializer）;
objectMapper = Jackson2ObjectMapperBuilder.json（）
.modules（模块）
.featuresToDisable（SerializationFeature.WRITE_DATES_AS_TIMESTAMPS）
.build（）;
}
@Test
public void test（）抛出IOException {
final String json ={\date\：\2016- 11-08 12：00}};
final JsonType instance = objectMapper.readValue（json，JsonType.class）;
assertEquals（LocalDateTime.parse（2016-11-08 12:00，DateTimeFormatter.ofPattern（yyyy-MM-dd HH：mm）），instance.getDate（））;
}
}
类JsonType {
private LocalDateTime date;
public LocalDateTime getDate（）{
return date;
}
public void setDate（LocalDateTime date）{
this.date = date;
}
}
I have read several questions with answers here in SO concerning serialization and deserialization between java.time.LocalDateTime and JSON property but I can't seem to get it working.
I have managed to configure my Spring Boot Application to return the dates in the format I desire (YYY-MM-dd HH:mm) but I have problems accepting values in this format in JSON.
These are all the things I have done so far:
Added maven dependency for jsr310:
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jsr310</artifactId>
</dependency>
Specified jsr310 in my main class:
@EntityScan(basePackageClasses = { App.class, Jsr310JpaConverters.class })
Disabled serialization as timestamps in application.properties:
spring.jackson.serialization.write_dates_as_timestamps=false
And this is my entity mapping for datetime:
@Column(name = "start_date")
@DateTimeFormat(iso = DateTimeFormat.ISO.TIME)
@JsonFormat(pattern = "YYYY-MM-dd HH:mm")
private LocalDateTime startDate;
In my database, I store this date as TIMESTAMP in the following format: 2016-12-01T23:00:00+00:00.
If I access this entity via my controller, it returns the JSON with correct startDate format. When I try to post it and deserialize it though, using YYYY-MM-dd HH:mm format, I get the following exception:
{
"timestamp": "2016-10-30T14:22:25.285+0000",
"status": 400,
"error": "Bad Request",
"exception": "org.springframework.http.converter.HttpMessageNotReadableException",
"message": "Could not read document: Can not deserialize value of type java.time.LocalDateTime from String \"2017-01-01 20:00\": Text '2017-01-01 20:00' could not be parsed: Unable to obtain LocalDateTime from TemporalAccessor: {MonthOfYear=1, WeekBasedYear[WeekFields[SUNDAY,1]]=2017, DayOfMonth=1},ISO resolved to 20:00 of type java.time.format.Parsed\n at [Source: java.io.PushbackInputStream@679a734d; line: 6, column: 16] (through reference chain: com.gigsterous.api.model.Event[\"startDate\"]); nested exception is com.fasterxml.jackson.databind.exc.InvalidFormatException: Can not deserialize value of type java.time.LocalDateTime from String \"2017-01-01 20:00\": Text '2017-01-01 20:00' could not be parsed: Unable to obtain LocalDateTime from TemporalAccessor: {MonthOfYear=1, WeekBasedYear[WeekFields[SUNDAY,1]]=2017, DayOfMonth=1},ISO resolved to 20:00 of type java.time.format.Parsed\n at [Source: java.io.PushbackInputStream@679a734d; line: 6, column: 16] (through reference chain: com.gigsterous.api.model.Event[\"startDate\"])",
"path": "/api/events"
}
I know that there are many answers concerning this topic but following them and trying for couple of hours did not help me to figure out what am I doing wrong so I would be glad if someone could point out to me what am I missing. Thanks for any input on this!
EDIT: These are all the classes involved in the process:
Repository:
@Repository
public interface EventRepository extends PagingAndSortingRepository<Event, Long> {
}
Controller:
@RequestMapping(method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<Event> createEvent(@RequestBody Event event) {
return new ResponseEntity<>(eventRepo.save(event), HttpStatus.CREATED);
}
My JSON request payalod:
{
"name": "Test",
"startDate": "2017-01-01 20:00"
}
Event:
@Entity
@Table(name = "events")
@Getter
@Setter
public class Event {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "event_id")
private long id;
@Column(name = "name")
private String name;
@Column(name = "start_date")
@DateTimeFormat(iso = DateTimeFormat.ISO.TIME)
@JsonFormat(pattern = "YYYY-MM-dd HH:mm")
private LocalDateTime startDate;
}
The date time you're passing is not a iso local date time format.
Change to
@Column(name = "start_date")
@DateTimeFormat(iso = DateTimeFormatter.ISO_LOCAL_DATE_TIME)
@JsonFormat(pattern = "YYYY-MM-dd HH:mm")
private LocalDateTime startDate;
and pass date string in the format '2011-12-03T10:15:30'.
But if you still want to pass your custom format, use just have to specify the right formatter.
Change to
@Column(name = "start_date")
@DateTimeFormat(iso = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm"))
@JsonFormat(pattern = "YYYY-MM-dd HH:mm")
private LocalDateTime startDate;
I think your problem is the @DateTimeFormat has no effect at all. As the jackson is doing the deseralization and it doesnt know anything about spring annotation and I dont see spring scanning this annotation in the deserialization context.
Alternatively, you can try setting the formatter while registering the java time module.
LocalDateTimeDeserializer localDateTimeDeserializer = new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm"));
module.addDeserializer(LocalDateTime.class, localDateTimeDeserializer);
Here is the test case with the deseralizer which works fine. May be try to get rid of that DateTimeFormat annotation altogether.
@RunWith(JUnit4.class)
public class JacksonLocalDateTimeTest {
private ObjectMapper objectMapper;
@Before
public void init() {
JavaTimeModule module = new JavaTimeModule();
LocalDateTimeDeserializer localDateTimeDeserializer = new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm"));
module.addDeserializer(LocalDateTime.class, localDateTimeDeserializer);
objectMapper = Jackson2ObjectMapperBuilder.json()
.modules(module)
.featuresToDisable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
.build();
}
@Test
public void test() throws IOException {
final String json = "{ \"date\": \"2016-11-08 12:00\" }";
final JsonType instance = objectMapper.readValue(json, JsonType.class);
assertEquals(LocalDateTime.parse("2016-11-08 12:00",DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm") ), instance.getDate());
}
}
class JsonType {
private LocalDateTime date;
public LocalDateTime getDate() {
return date;
}
public void setDate(LocalDateTime date) {
this.date = date;
}
}
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