Admin: 1 версия

2010-06-01T05:18:26Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== Attribute Overrides For Embeddable ID ==

File: Employee.java



<source lang="java">
import javax.persistence.AttributeOverride;
import javax.persistence.AttributeOverrides;
import javax.persistence.Column;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.Transient;
@Entity
public class Employee implements java.io.Serializable {
private String firstName;
private EmployeePK pk;
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
@EmbeddedId
@AttributeOverrides( {
@AttributeOverride(name = "lastName", column = @Column(name = "LAST_NAME")),
@AttributeOverride(name = "ssn", column = @Column(name = "SSN")) })
public EmployeePK getPk() {
return pk;
}
public void setPk(EmployeePK pk) {
this.pk = pk;
}
@Transient
public String getLastName() {
return pk.getLastName();
}
@Transient
public long getSsn() {
return pk.getSsn();
}
}</source>



== Attribute Overrides For Secondary Table ==

File: Main.java



<source lang="java">
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
static EntityManager em = emf.createEntityManager();
public static void main(String[] a) throws Exception {
em.getTransaction().begin();

Student student = new Student();
student.setId(1);
student.setName("Tom");
Address addr = new Address();
addr.setStreet("street 1");
addr.setCity("LA");
addr.setState("CA");
addr.setZip("asdfasdf");
student.setAddress(addr);
em.persist(student);

em.getTransaction().rumit();
em.close();
emf.close();
Helper.checkData();
}
}</source>



== Subclass With Attribute Overrides ==

File: Employee.java



<source lang="java">
import java.util.Date;
import javax.persistence.AttributeOverride;
import javax.persistence.AttributeOverrides;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.InheritanceType;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
@Entity
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
public abstract class Employee {
@Id
private int id;
private String name;
@Temporal(TemporalType.DATE)
private Date startDate;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getStartDate() {
return startDate;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
public String toString() {
return "Employee id: " + getId() + " name: " + getName();
}
}
@Entity
@Table(name="CONTRACT_EMP")
@AttributeOverrides({
@AttributeOverride(name="name", column=@Column(name="FULLNAME")),
@AttributeOverride(name="startDate", column=@Column(name="SDATE"))
})
class ContractEmployee extends Employee {
@Column(name="D_RATE")
private int dailyRate;
private int term;

public int getDailyRate() {
return dailyRate;
}

public void setDailyRate(int dailyRate) {
this.dailyRate = dailyRate;
}

public int getTerm() {
return term;
}

public void setTerm(int term) {
this.term = term;
}
public String toString() {
return "ContractEmployee id: " + getId() + " name: " + getName();
}
}</source>



== Using Attribute Overrides ==

File: Main.java



<source lang="java">
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
static EntityManager em = emf.createEntityManager();
public static void main(String[] a) throws Exception {
em.getTransaction().begin();
Student student = new Student();
student.setId(1);
student.setName("name");
Address addr = new Address();
addr.setStreet("street1");
addr.setCity("city1");
addr.setState("state1");
addr.setZip("asdfasdf");
student.setAddress(addr);
em.persist(student);

Company c = new Company();
c.setName("III");
addr = new Address();
addr.setStreet("street2");
addr.setCity("city2");
addr.setState("state2");
addr.setZip("asdfasdf");
c.setAddress(addr);
em.persist(c);

em.getTransaction().rumit();
em.close();
emf.close();
Helper.checkData();
}
}</source>

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Admin: 1 версия

в 17:44, 31 мая 2010