Java 如何使用JPA持久化LocalDate?
我想将没有时间的日期存储到我的数据库中。因此,我选择使用Java 如何使用JPA持久化LocalDate?,java,spring,spring-boot,java-8,spring-data-jpa,Java,Spring,Spring Boot,Java 8,Spring Data Jpa,我想将没有时间的日期存储到我的数据库中。因此,我选择使用LocalDatetype 如中所述,我使用JPA转换器将LocalDate转换为Date 然而,当我想要持久化我的实体(使用POST和PUT请求)时,我遇到了一些麻烦 错误 2019-02-23 11:26:30.254 WARN 2720 --- [-auto-1-exec-10] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.http
LocalDate
type
如中所述,我使用JPA转换器将LocalDate
转换为Date
然而,当我想要持久化我的实体(使用POST和PUT请求)时,我遇到了一些麻烦
错误
2019-02-23 11:26:30.254 WARN 2720 --- [-auto-1-exec-10] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Expected array or string.; nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Expected array or string.
at [Source: (PushbackInputStream); line: 1, column: 104] (through reference chain: ...entity.MyObject["startdate"])]
org.springframework.http.converter.HttpMessageConversionException: Type definition error: [simple type, class org.springframework.http.ResponseEntity]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `org.springframework.http.ResponseEntity` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
at [Source: (PushbackInputStream); line: 1, column: 2]
代码
转换器
“主要”
谢谢你的帮助
编辑1:打印MyObject
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON);
HttpEntity<String> entity = new HttpEntity<>(this.toJsonString(myObject), headers);
System.out.println(entity.toString());
// <{"id":"ba6649e4-6e65-4f54-8f1a-f8fc7143b05a","startdate":{"year":2019,"month":"FEBRUARY","dayOfMonth":23,"dayOfWeek":"SATURDAY","era":"CE","dayOfYear":54,"leapYear":false,"monthValue":2,"chronology":{"id":"ISO","calendarType":"iso8601"}},"enddate":{"year":2019,"month":"MARCH","dayOfMonth":1,"dayOfWeek":"FRIDAY","era":"CE","dayOfYear":60,"leapYear":false,"monthValue":3,"chronology":{"id":"ISO","calendarType":"iso8601"}}},[Content-Type:"application/json"]>
HttpHeaders=newhttpheaders();
headers.setContentType(MediaType.APPLICATION_JSON);
HttpEntity=新的HttpEntity(this.toJsonString(myObject),头文件);
System.out.println(entity.toString());
//
Hibernate 5支持java 8,因此您可以将其添加到pom.xml中:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-java8</artifactId>
<version>5.1.0.Final</version>
</dependency>
org.hibernate
hibernate-java8
5.1.0.1最终版本
这为您提供了现成的
LocalDate
和LocalDateTime
映射。jpa2.2支持LocalDate
,因此不需要转换器
Hibernate从5.3版开始也支持它
查看了解更多详细信息。我认为您可以编写自己的转换器,请检查答案:对于JPA 2.2,您不再需要使用转换器,它添加了对以下java.time类型映射的支持:
java.time.LocalDate
java.time.LocalTime
java.time.LocalDateTime
java.time.OffsetTime
java.time.OffsetDateTime
JPA2.2增加了对映射Java8日期/时间API的支持,如
LocalDate
,LocalTime
,LocalDateTime
,OffsetDateTime
或OffsetTime
那么,假设我们有以下实体:
@Entity(name = "UserAccount")
@Table(name = "user_account")
public class UserAccount {
@Id
private Long id;
@Column(name = "first_name", length = 50)
private String firstName;
@Column(name = "last_name", length = 50)
private String lastName;
@Column(name = "subscribed_on")
private LocalDate subscribedOn;
//Getters and setters omitted for brevity
}
请注意,subscribedOn
属性是一个LocalDate
Java对象
持久化用户帐户时
:
UserAccount user = new UserAccount()
.setId(1L)
.setFirstName("Vlad")
.setLastName("Mihalcea")
.setSubscribedOn(
LocalDate.of(
2013, 9, 29
)
);
entityManager.persist(user);
Hibernate生成正确的SQL INSERT语句:
INSERT INTO user_account (
first_name,
last_name,
subscribed_on,
id
)
VALUES (
'Vlad',
'Mihalcea',
'2013-09-29',
1
)
在获取UserAccount
实体时,我们可以看到LocalDate
正确地从数据库中获取:
UserAccount userAccount = entityManager.find(
UserAccount.class, 1L
);
assertEquals(
LocalDate.of(
2013, 9, 29
),
userAccount.getSubscribedOn()
);
所以JSON中有一个错误,它不是JPA。即使是JPA,您也需要提到您使用的JPA提供商,以及您认为本地日期处理不当的地方。您的调试是什么say@BillyFrost我编辑了我的问题。我在
JSON
中打印myObject
。该格式不是我的格式化程序中指定的格式…它无法隔离问题所在。您在JPA中的问题是没有将数据持久化到数据库中,还是没有从数据库中检索数据。。。。或者只是将Java对象转换成JSON?????如果问题在持久性中,那么定义使用什么SQL来持久化,以及您认为该SQL的问题在哪里。。。“坚持”不涉及POST/PUT。。。它涉及JPA em.persist。因此,我不明白的是为什么sysout()
中的格式不是yyyy-MM-dd
。因为如果我执行sysout(myObject.getStartdate())
的话,结果是日期的格式是yyyy-MM-dd
好的,那么与JPA无关。LocalDate
.toString()方法有自己的输出格式,由JAVADOCS定义,这与“问题”有什么关系?如果我有LocalDate可选项,并将其发送为null,oracle将返回:expected date get binary,如果我使用java.util.date,则不会发生这种情况。我如何用jpa解决这个问题?
@Entity(name = "UserAccount")
@Table(name = "user_account")
public class UserAccount {
@Id
private Long id;
@Column(name = "first_name", length = 50)
private String firstName;
@Column(name = "last_name", length = 50)
private String lastName;
@Column(name = "subscribed_on")
private LocalDate subscribedOn;
//Getters and setters omitted for brevity
}
UserAccount user = new UserAccount()
.setId(1L)
.setFirstName("Vlad")
.setLastName("Mihalcea")
.setSubscribedOn(
LocalDate.of(
2013, 9, 29
)
);
entityManager.persist(user);
INSERT INTO user_account (
first_name,
last_name,
subscribed_on,
id
)
VALUES (
'Vlad',
'Mihalcea',
'2013-09-29',
1
)
UserAccount userAccount = entityManager.find(
UserAccount.class, 1L
);
assertEquals(
LocalDate.of(
2013, 9, 29
),
userAccount.getSubscribedOn()
);