Seven Entities : Introduction « JPA « Java Tutorial

1. Java Tutorial
2. JPA
3. Introduction

File: Address.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Address implements java.io.Serializable {
  private int id;

  private String street;

  private String city;

  private String state;

  private String zip;

  @Id
  @GeneratedValue
  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getStreet() {
    return street;
  }

  public void setStreet(String street) {
    this.street = street;
  }

  public String getCity() {
    return city;
  }

  public void setCity(String city) {
    this.city = city;
  }

  public String getState() {
    return state;
  }

  public void setState(String state) {
    this.state = state;
  }

  public String getZip() {
    return zip;
  }

  public void setZip(String zip) {
    this.zip = zip;
  }
}

File: CreditCard.java

import java.util.Date;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToOne;

@Entity
public class CreditCard implements java.io.Serializable {
  private int id;

  private Date expirationDate;

  private String number;

  private String nameOnCard;

  private String creditOrganization;

  private Customer customer;

  @Id
  @GeneratedValue
  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public Date getExpirationDate() {
    return expirationDate;
  }

  public void setExpirationDate(Date date) {
    expirationDate = date;
  }

  public String getNumber() {
    return number;
  }

  public void setNumber(String number) {
    this.number = number;
  }

  public String getNameOnCard() {
    return nameOnCard;
  }

  public void setNameOnCard(String name) {
    nameOnCard = name;
  }

  public String getCreditOrganization() {
    return creditOrganization;
  }

  public void setCreditOrganization(String org) {
    creditOrganization = org;
  }

  @OneToOne(mappedBy = "creditCard")
  public Customer getCustomer() {
    return customer;
  }

  public void setCustomer(Customer customer) {
    this.customer = customer;
  }
}

File: Cruise.java

import java.util.ArrayList;
import java.util.Collection;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;

@Entity
public class Cruise implements java.io.Serializable {
  private int id;

  private String name;

  private Ship ship;

  private Collection<Reservation> reservations = new ArrayList<Reservation>();

  public Cruise() {
  }

  public Cruise(String name, Ship ship) {
    this.name = name;
    this.ship = ship;
  }

  @Id
  @GeneratedValue
  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;
  }

  @ManyToOne
  public Ship getShip() {
    return ship;
  }

  public void setShip(Ship ship) {
    this.ship = ship;
  }

  @OneToMany(mappedBy = "cruise")
  public Collection<Reservation> getReservations() {
    return reservations;
  }

  public void setReservations(Collection<Reservation> res) {
    reservations = res;
  }
}

File: Customer.java

import java.util.ArrayList;
import java.util.Collection;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToMany;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;

@Entity
public class Customer implements java.io.Serializable {

  @Id
  @GeneratedValue
  private int id;

  private String firstName;

  @OneToOne(cascade = { CascadeType.ALL })
  @JoinColumn(name = "ADDRESS_ID")
  private Address address;

  @OneToMany(cascade = { CascadeType.ALL })
  @JoinColumn(name = "CUSTOMER_ID")
  private Collection<Phone> phoneNumbers = new ArrayList<Phone>();

  @OneToOne(cascade = { CascadeType.ALL })
  private CreditCard creditCard;

  @ManyToMany(mappedBy = "customers")
  private Collection<Reservation> reservations = new ArrayList<Reservation>();

  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getFirstName() {
    return firstName;
  }

  public void setFirstName(String firstName) {
    this.firstName = firstName;
  }

  public Address getAddress() {
    return address;
  }

  public void setAddress(Address address) {
    this.address = address;
  }

  public CreditCard getCreditCard() {
    return creditCard;
  }

  public void setCreditCard(CreditCard card) {
    creditCard = card;
  }

  public Collection<Phone> getPhoneNumbers() {
    return phoneNumbers;
  }

  public void setPhoneNumbers(Collection<Phone> phones) {
    this.phoneNumbers = phones;
  }

  public Collection<Reservation> getReservations() {
    return reservations;
  }

  public void setReservations(Collection<Reservation> reservations) {
    this.reservations = reservations;
  }
}

File: Phone.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Phone implements java.io.Serializable {
  private int id;

  private String number;

  private byte type;

  @Id
  @GeneratedValue
  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getNumber() {
    return number;
  }

  public void setNumber(String number) {
    this.number = number;
  }

  public byte getType() {
    return type;
  }

  public void setType(byte type) {
    this.type = type;
  }
}

File: Reservation.java

import java.util.Date;
import java.util.HashSet;
import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;

@Entity
public class Reservation implements java.io.Serializable {
  private int id;
  private Cruise cruise;
  private Set<Customer> customers = new HashSet<Customer>();

  @Id
  @GeneratedValue
  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  @ManyToOne
  @JoinColumn(name = "CRUISE_ID")
  public Cruise getCruise() {
    return cruise;
  }

  public void setCruise(Cruise cruise) {
    this.cruise = cruise;
  }

  @ManyToMany
  @JoinTable(name = "RESERVATION_CUSTOMER", joinColumns = { @JoinColumn(name = "RESERVATION_ID") }, inverseJoinColumns = { @JoinColumn(name = "CUSTOMER_ID") })
  public Set<Customer> getCustomers() {
    return customers;
  }

  public void setCustomers(Set<Customer> customers) {
    this.customers = customers;
  }
}

File: Ship.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Ship implements java.io.Serializable {
  private int id;

  private String name;
  public Ship() {
  }

  public Ship(String name) {
    this.name = name;
  }

  @Id
  @GeneratedValue
  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;
  }

}

File: Helper.java

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;

public class Helper {
  public static void checkData() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
    Statement st = conn.createStatement();

    ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
    while (mrs.next()) {
      String tableName = mrs.getString(3);
      System.out.println("\n\n\n\nTable Name: "+ tableName);

      ResultSet rs = st.executeQuery("select * from " + tableName);
      ResultSetMetaData metadata = rs.getMetaData();
      while (rs.next()) {
        System.out.println(" Row:");
        for (int i = 0; i < metadata.getColumnCount(); i++) {
          System.out.println("    Column Name: "+ metadata.getColumnLabel(i + 1)+ ",  ");
          System.out.println("    Column Type: "+ metadata.getColumnTypeName(i + 1)+ ":  ");
          Object value = rs.getObject(i + 1);
          System.out.println("    Column Value: "+value+"\n");
        }
      }
    }
  }
}

File: Main.java

import java.util.List;

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();




    em.getTransaction().commit();
    em.close();
    emf.close();

    Helper.checkData();
  }
}

File: persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>

22.1.Introduction
	22.1.1.	JPA Development Environment Setup
	22.1.2.	Persistance Configuration
	22.1.3.	Seven Entities
	22.1.4.	Mark Class As Entity
	22.1.5.	Set Column Name For Accessor
	22.1.6.	Mark Property Accessor
	22.1.7.	Field Injection ID