Java Spring REST-@createdDate在抽象超类中抛出错误

我在春季休息方面遇到了麻烦（新来的）

我的意图是创建一个抽象的超类，其中包含一些公共字段，比如ID/Version/CreatedDate等等。 它在JPA和数据库方面工作得很好。但是，当我试图使用某个存储库

paging和sortingrepository

公开子级时，一旦查询api，就会出现以下错误

其他领域的工作还不错。它与@CreatedDate注释相对应

错误：

Resolved exception caused by Handler execution:        
org.springframework.http.converter.HttpMessageNotWritableException:
Could not write JSON: java.sql.Date cannot be cast to java.lang.String; 
nested exception is com.fasterxml.jackson.databind.JsonMappingException: 
java.sql.Date cannot be cast to java.lang.String (through reference chain: 
org.springframework.hateoas.PagedResources["_embedded"]-
java.util.Collections$UnmodifiableMap["users"]->java.util.ArrayList[0]org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$PersistentEntityResourceSerializer$1["content"]->com.*.*.domain.User["createdDate"])

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
public abstract class AbstractPersistentObject
    implements PersistentObject, Serializable {

@Id
@GeneratedValue(strategy= GenerationType.AUTO)
protected Long id;
protected Integer version;

@org.springframework.data.annotation.CreatedDate
@Temporal(TemporalType.DATE)
public Date createdDate;

... getter / setter / constructor

protected Date getCreatedDate() {
    return createdDate;
}

protected void setCreatedDate(Date createdDate) {
    this.createdDate = createdDate;
}

@Entity
@Table(name = "UserTable")
public class User extends AbstractPersistentObject {

private String firstName;
private String lastName;

@NotNull
@Column(unique = true)
private String email;
@JsonIgnore
private String password;

private boolean verified;
...

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

Super:

Resolved exception caused by Handler execution:        
org.springframework.http.converter.HttpMessageNotWritableException:
Could not write JSON: java.sql.Date cannot be cast to java.lang.String; 
nested exception is com.fasterxml.jackson.databind.JsonMappingException: 
java.sql.Date cannot be cast to java.lang.String (through reference chain: 
org.springframework.hateoas.PagedResources["_embedded"]-
java.util.Collections$UnmodifiableMap["users"]->java.util.ArrayList[0]org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$PersistentEntityResourceSerializer$1["content"]->com.*.*.domain.User["createdDate"])

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
public abstract class AbstractPersistentObject
    implements PersistentObject, Serializable {

@Id
@GeneratedValue(strategy= GenerationType.AUTO)
protected Long id;
protected Integer version;

@org.springframework.data.annotation.CreatedDate
@Temporal(TemporalType.DATE)
public Date createdDate;

... getter / setter / constructor

protected Date getCreatedDate() {
    return createdDate;
}

protected void setCreatedDate(Date createdDate) {
    this.createdDate = createdDate;
}

@Entity
@Table(name = "UserTable")
public class User extends AbstractPersistentObject {

private String firstName;
private String lastName;

@NotNull
@Column(unique = true)
private String email;
@JsonIgnore
private String password;

private boolean verified;
...

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

示例子项：

Resolved exception caused by Handler execution:        
org.springframework.http.converter.HttpMessageNotWritableException:
Could not write JSON: java.sql.Date cannot be cast to java.lang.String; 
nested exception is com.fasterxml.jackson.databind.JsonMappingException: 
java.sql.Date cannot be cast to java.lang.String (through reference chain: 
org.springframework.hateoas.PagedResources["_embedded"]-
java.util.Collections$UnmodifiableMap["users"]->java.util.ArrayList[0]org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$PersistentEntityResourceSerializer$1["content"]->com.*.*.domain.User["createdDate"])

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
public abstract class AbstractPersistentObject
    implements PersistentObject, Serializable {

@Id
@GeneratedValue(strategy= GenerationType.AUTO)
protected Long id;
protected Integer version;

@org.springframework.data.annotation.CreatedDate
@Temporal(TemporalType.DATE)
public Date createdDate;

... getter / setter / constructor

protected Date getCreatedDate() {
    return createdDate;
}

protected void setCreatedDate(Date createdDate) {
    this.createdDate = createdDate;
}

@Entity
@Table(name = "UserTable")
public class User extends AbstractPersistentObject {

private String firstName;
private String lastName;

@NotNull
@Column(unique = true)
private String email;
@JsonIgnore
private String password;

private boolean verified;
...

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

---

解决方案：

Resolved exception caused by Handler execution:        
org.springframework.http.converter.HttpMessageNotWritableException:
Could not write JSON: java.sql.Date cannot be cast to java.lang.String; 
nested exception is com.fasterxml.jackson.databind.JsonMappingException: 
java.sql.Date cannot be cast to java.lang.String (through reference chain: 
org.springframework.hateoas.PagedResources["_embedded"]-
java.util.Collections$UnmodifiableMap["users"]->java.util.ArrayList[0]org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$PersistentEntityResourceSerializer$1["content"]->com.*.*.domain.User["createdDate"])

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
public abstract class AbstractPersistentObject
    implements PersistentObject, Serializable {

@Id
@GeneratedValue(strategy= GenerationType.AUTO)
protected Long id;
protected Integer version;

@org.springframework.data.annotation.CreatedDate
@Temporal(TemporalType.DATE)
public Date createdDate;

... getter / setter / constructor

protected Date getCreatedDate() {
    return createdDate;
}

protected void setCreatedDate(Date createdDate) {
    this.createdDate = createdDate;
}

@Entity
@Table(name = "UserTable")
public class User extends AbstractPersistentObject {

private String firstName;
private String lastName;

@NotNull
@Column(unique = true)
private String email;
@JsonIgnore
private String password;

private boolean verified;
...

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

---

尝试从包中使用@CreatedDate:

org.springframework.data.annotation.CreatedDate

在类

AbstractPersistentObject

中，实例变量

CreatedDate

声明为public，而getter和setter声明为protected。尝试反向访问，以便getter和setter是公共的，而实例变量是受保护的（或私有的）。

感谢您的支持

我没有搞砸！我目前使用的是Spring boot 2.0.0.M2。我更新到2.0.0.M3，它就可以工作了

我很快调查了回购协议，但没有发现任何关于我们的信息

解决方案：

Resolved exception caused by Handler execution:        
org.springframework.http.converter.HttpMessageNotWritableException:
Could not write JSON: java.sql.Date cannot be cast to java.lang.String; 
nested exception is com.fasterxml.jackson.databind.JsonMappingException: 
java.sql.Date cannot be cast to java.lang.String (through reference chain: 
org.springframework.hateoas.PagedResources["_embedded"]-
java.util.Collections$UnmodifiableMap["users"]->java.util.ArrayList[0]org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$PersistentEntityResourceSerializer$1["content"]->com.*.*.domain.User["createdDate"])

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
public abstract class AbstractPersistentObject
    implements PersistentObject, Serializable {

@Id
@GeneratedValue(strategy= GenerationType.AUTO)
protected Long id;
protected Integer version;

@org.springframework.data.annotation.CreatedDate
@Temporal(TemporalType.DATE)
public Date createdDate;

... getter / setter / constructor

protected Date getCreatedDate() {
    return createdDate;
}

protected void setCreatedDate(Date createdDate) {
    this.createdDate = createdDate;
}

@Entity
@Table(name = "UserTable")
public class User extends AbstractPersistentObject {

private String firstName;
private String lastName;

@NotNull
@Column(unique = true)
private String email;
@JsonIgnore
private String password;

private boolean verified;
...

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

Upgrading Spring Boot from 2.0.0.M2 to 2.0.0.M3.

---

应该早点检查这一点，因为在使用此版本时，不知何故它是预期的

该错误表示存在数据类型转换问题。请包括

AbstractPersistentObject

中

createdDate

的getter和setter。我包括了该字段的getter setter。回复的Thx您的项目中是否有注释

@EnableJpaAuditing

？是的，我让createdDate注释工作。他们在儿童班的时候就工作。我查过了。遗憾的是，这是正确的，但我之前没有确定^^^是的，我已经和thoose玩过了。谢谢你的回复，我通过升级Spring Boot解决了这个问题。很高兴知道你解决了这个问题。为我没有要求版本信息而感到羞耻。我只是假设你使用的是一个稳定的版本，而不是一个里程碑式的版本。是的，我应该首先提到这一点。这只是一个用于学习目的的项目，所以我认为它会很好…：）