File: Main.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().commit(); em.close(); emf.close(); Helper.checkData(); } }
File: Student.java
import javax.persistence.AttributeOverride; import javax.persistence.AttributeOverrides; import javax.persistence.Column; import javax.persistence.Embedded; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.PrimaryKeyJoinColumn; import javax.persistence.SecondaryTable; import javax.persistence.Table; @Entity @Table(name="Student") @SecondaryTable(name="Student_ADDRESS", pkJoinColumns=@PrimaryKeyJoinColumn(name="Student_ID")) public class Student { @Id private int id; private String name; @Embedded @AttributeOverrides({ @AttributeOverride(name="street", column=@Column(table="Student_ADDRESS")), @AttributeOverride(name="city", column=@Column(name="CITY", table="Student_ADDRESS")), @AttributeOverride(name="state", column=@Column(name="STATE", table="Student_ADDRESS")), @AttributeOverride(name="zip", column=@Column(name="ZIP_CODE", table="Student_ADDRESS")) }) 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 "Student id: " + getId() + " name: " + getName() + " with " + getAddress(); } }
File: Address.java
import javax.persistence.Column; import javax.persistence.Embeddable; @Embeddable public class Address { private String street; private String city; private String state; @Column(name="ZIP_CODE") private String zip; 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 street: " + getStreet() + ", city: " + getCity() + ", state: " + getState() + ", zip: " + getZip(); } }
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: 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>
22.31.Attribute Overrides | ||||
22.31.1. | Using Attribute Overrides | ![]() | ||
22.31.2. | Attribute Overrides For Secondary Table | ![]() | ||
22.31.3. | Attribute Overrides For Embeddable ID | ![]() | ||
22.31.4. | Subclass With Attribute Overrides | ![]() |