Java tutorial
File:Address.java import javax.persistence.Entity; import javax.persistence.Id; @Entity public class Address { @Id private int id; private String street; private String city; private String state; private String zip; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getStreet() { return street; } public void setStreet(String address) { this.street = address; } 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; } public String toString() { return "Address id: " + getId() + ", street: " + getStreet() + ", city: " + getCity() + ", state: " + getState() + ", zip: " + getZip(); } } File:Student.java import javax.persistence.CascadeType; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.OneToOne; @Entity public class Student { @Id private int id; private String name; @OneToOne(cascade=CascadeType.ALL) private Address address; 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 Address getAddress() { return address; } public void setAddress(Address address) { this.address = address; } public String toString() { return "\n\nID:" + id + "\nName:" + name + "\n\n"; } } 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(); Student student = new Student(); student.setName("Joe"); Address address = new Address(); address.setCity("city"); // em.persist(address); student.setAddress(address); em.persist(student); em.flush(); em.getTransaction().commit(); Query query = em.createQuery("SELECT e FROM Student e"); List<Student> list = (List<Student>) query.getResultList(); System.out.println(list.get(0).getAddress()); 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>