Worker.java
import javax.jdo.annotations.IdGeneratorStrategy;
import javax.jdo.annotations.Inheritance;
import javax.jdo.annotations.InheritanceStrategy;
import javax.jdo.annotations.PersistenceCapable;
import javax.jdo.annotations.Persistent;
import javax.jdo.annotations.PrimaryKey;
@PersistenceCapable
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)
public abstract class Worker {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
@Persistent
private String department;
}
Employee.java
// ... imports ...
@PersistenceCapable
public class Employee extends Worker {
@Persistent
private int salary;
}
Intern.java
import java.util.Date;
// ... imports ...
@PersistenceCapable
public class Intern extends Worker {
@Persistent
private Date internshipEndDate;
}
Human.java
@PersistenceCapable
public abstract class Human {
@Persistent
private String name;
}
Worker.java
@PersistenceCapable
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)
public abstract class Worker extends Human {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
@Persistent
private String department;
}
答案 0 :(得分:0)
您的主键现在不在(可持久的)继承树的根类中,因此JDO和JPA规范无效。
答案 1 :(得分:0)
您还应该将以下声明移至Human类:
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)