Question

我正在使用Spring启动和JPA处理restfull Web服务，但我遇到了类似的问题

[错误]无法执行目标 org.springframework.boot：弹簧启动了Maven插件：1.5.3.RELEASE：运行项目SpringRest上的（default-cli）：发生异常时运行。 null：InvocationTargetException：创建bean时出错在类路径资源中定义的名称“entityManagerFactory” [组织/ springframework的/引导/自动配置/ ORM / JPA / HibernateJpaAutoConfiguration.class]：调用init方法失败;嵌套异常是 org.hibernate.AnnotationException：@Column不允许在 @ManyToOne属性：com.maven.nurcanyilmaz.models.Employee.department

的pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.3.RELEASE</version>
</parent>

<dependencies>

 <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-rest</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>

    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
    </dependency>
    <!-- JSTL for JSP -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
    </dependency>

    <!-- For JSP compilation -->
    <dependency>
        <groupId>org.apache.tomcat.embed</groupId>
        <artifactId>tomcat-embed-jasper</artifactId>
        <scope>provided</scope>
    </dependency>
    <dependency>
  <groupId>javax.transaction</groupId>
  <artifactId>jta</artifactId>
  <version>1.1</version>
  </dependency>

  <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.5</version>
    </dependency>

   <dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>3.8.1</version>
     <scope>test</scope>
  </dependency>
</dependencies>

实体

@Entity
@Table(name="DEPARTMENT")
public class Department {

    @Id
    @Column(name="Id",nullable=false,unique=true)
    @GeneratedValue(strategy=GenerationType.AUTO)
    private int id;
    @Column(name="Description",nullable=false)
    private String description;

    @OneToMany(mappedBy = "department", cascade = CascadeType.ALL)
    private List<Employee> employees;

    public Department() {
        // TODO Auto-generated constructor stub
    }

   @Entity
@Table(name="EMPLOYEE")
public class Employee {

    @Id
    @Column(name="Id",nullable=false,unique=true)
    @GeneratedValue(strategy=GenerationType.AUTO)
    private long id;

    @Column(name="Name",nullable=false)
    private String name;

    @Column(name="Surname",nullable=false)
    private String surname;
    @Column(name="Salary",nullable=false)
    private double salary;

    @Column(name="Department" , nullable=false)
    @ManyToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "Id",referencedColumnName="Id")
    private Department department;

    public Employee() {
        // TODO Auto-generated constructor stub
    }

存储库

import com.maven.nurcanyilmaz.models.Employee;
import org.springframework.data.repository.CrudRepository;
import org.springframework.data.rest.core.annotation.RepositoryRestResource;

@RepositoryRestResource
public interface EmployeeRepository extends CrudRepository<Employee, Long> {

    Employee findByName(String name);

}


import org.springframework.data.repository.CrudRepository;
import org.springframework.data.rest.core.annotation.RepositoryRestResource;

import com.maven.nurcanyilmaz.models.Department;

@RepositoryRestResource
public interface DepartmentRepository extends CrudRepository<Department, Long> {

    Department findByName(String name);
}

application.properties

 spring.mvc.view.prefix: /WEB-INF/
spring.mvc.view.suffix: .jsp
server.port=8088

spring.datasource.url = jdbc:mysql://localhost:3306/EmployeeDb
spring.datasource.username =root
spring.datasource.password =test
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

# Keep the connection alive if idle for a long time (needed in production)
spring.datasource.testWhileIdle = true
spring.datasource.validationQuery = SELECT 1

# Show or not log for each sql query
spring.jpa.show-sql = true

# Hibernate ddl auto (create, create-drop, update)
spring.jpa.hibernate.ddl-auto = create-drop

spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy


spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
server.error.whitelabel.enabled=false

Answer 1

在私人部门的员工实体中，您正在使用@column和@joinColumn，这似乎是问题所在。看看你的实体，你应该在那里使用@JoinColumn而不是@Column。

Answer 2

Hibernate不允许@Column注释与@ManyToOne一起使用。

如果要指定列名

，可以使用@JoinColumn

Answer 3

由于错误说明建议您不应在@Column媒体资源上添加@ManyToOne注释。你需要@JoinColumn。

请参阅https://en.wikibooks.org/wiki/Java_Persistence/ManyToOne

未定义Spring Boot EntityManagerFactory且不允许@ManyToOne

3 个答案: