File: Main.java
import java.util.Date; 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.setId(1); student.setName("Joe"); student.setDateOfBirth(new Date()); student.setGender(Gender.FEMALE); em.persist(student); em.flush(); Student st = em.find(Student.class, student.getId()); System.out.println(st); em.getTransaction().commit(); em.close(); emf.close(); Helper.checkData(); } }
File: Student.java
import java.util.Date; import javax.persistence.Entity; import javax.persistence.EnumType; import javax.persistence.Enumerated; import javax.persistence.Id; @Entity public class Student { @Id private long id = 0; private String name; private Date dateOfBirth = new Date(); @Enumerated(EnumType.ORDINAL) private Gender gender; public Date getDateOfBirth() { return dateOfBirth; } public void setDateOfBirth(Date dateOfBirth) { this.dateOfBirth = dateOfBirth; } public long getId() { return id; } public void setId(long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public Gender getGender() { return gender; } public void setGender(Gender gender) { this.gender = gender; } public String toString() { return "\n\nID:" + id + "\nName:" + name + "\nBirthday:" + dateOfBirth + "\nGender:" + gender+"\n\n"; } }
File: Gender.java
public enum Gender { MALE, FEMALE }
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>
22.35.Transaction | ||||
22.35.1. | Roll Back A Transaction | ![]() | ||
22.35.2. | Commit a Transaction | ![]() |