build.gradle
group 'ir.mhdr' version '1.0-SNAPSHOT' apply plugin: 'java' sourceCompatibility = 1.8 mainClassName="Main" repositories { mavenCentral() } dependencies { // https://mvnrepository.com/artifact/org.hibernate/hibernate-core compile group: 'org.hibernate', name: 'hibernate-core', version: '5.2.10.Final' // https://mvnrepository.com/artifact/org.hibernate/hibernate-gradle-plugin compile group: 'org.hibernate', name: 'hibernate-gradle-plugin', version: '5.2.10.Final' // https://mvnrepository.com/artifact/mysql/mysql-connector-java compile group: 'mysql', name: 'mysql-connector-java', version: '6.0.6' // https://mvnrepository.com/artifact/org.slf4j/slf4j-api compile group: 'org.slf4j', name: 'slf4j-api', version: '1.7.25' // https://mvnrepository.com/artifact/org.slf4j/slf4j-simple testCompile group: 'org.slf4j', name: 'slf4j-simple', version: '1.7.25' testCompile group: 'junit', name: 'junit', version: '4.12' }
Employee.java
import javax.persistence.*; @Entity @Table(name = "EMPLOYEE") public class Employee { @Id @GeneratedValue @Column(name = "id") private int id; @Column(name = "first_name") private String firstName; @Column(name = "last_name") private String lastName; @Column(name = "salary") private int salary; public Employee() { } public Employee(String fname, String lname, int salary) { this.firstName = fname; this.lastName = lname; this.salary = salary; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getFirstName() { return firstName; } public void setFirstName(String first_name) { this.firstName = first_name; } public String getLastName() { return lastName; } public void setLastName(String last_name) { this.lastName = last_name; } public int getSalary() { return salary; } public void setSalary(int salary) { this.salary = salary; } }
resources/hibernate.cfg.xml
<?xml version="1.0" encoding="utf-8"?> <!DOCTYPE hibernate-configuration SYSTEM "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <property name="hibernate.hbm2ddl.auto">create</property> <property name="hibernate.show_sql">true</property> <property name="hibernate.format_sql">true</property> <property name="hibernate.dialect"> org.hibernate.dialect.MySQL57Dialect </property> <property name="hibernate.connection.driver_class"> com.mysql.cj.jdbc.Driver </property> <!-- Assume test is the database name --> <property name="hibernate.connection.url"> jdbc:mysql://localhost/testdb?useUnicode=yes&characterEncoding=UTF-8&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC </property> <property name="hibernate.connection.username"> root </property> <property name="hibernate.connection.password"> sampad622 </property> <!-- List of XML mapping files --> <mapping class="Employee"/> </session-factory> </hibernate-configuration>
ManageEmployee.java
import org.hibernate.HibernateException; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.Transaction; import org.hibernate.cfg.Configuration; import java.util.Iterator; import java.util.List; public class ManageEmployee { private SessionFactory factory; public ManageEmployee() { factory = new Configuration().configure().buildSessionFactory(); } /* Method to CREATE an employee in the database */ public Integer addEmployee(String fname, String lname, int salary) { Session session = factory.openSession(); Transaction tx = null; Integer employeeID = null; try { tx = session.beginTransaction(); Employee employee = new Employee(fname, lname, salary); employeeID = (Integer) session.save(employee); tx.commit(); } catch (HibernateException e) { if (tx != null) tx.rollback(); e.printStackTrace(); } finally { session.close(); } return employeeID; } /* Method to READ all the employees */ public void listEmployees() { Session session = factory.openSession(); Transaction tx = null; try { tx = session.beginTransaction(); List employees = session.createQuery("FROM Employee").list(); for (Iterator iterator = employees.iterator(); iterator.hasNext(); ) { Employee employee = (Employee) iterator.next(); System.out.print("First Name: " + employee.getFirstName()); System.out.print(" Last Name: " + employee.getLastName()); System.out.println(" Salary: " + employee.getSalary()); } tx.commit(); } catch (HibernateException e) { if (tx != null) tx.rollback(); e.printStackTrace(); } finally { session.close(); } } /* Method to UPDATE salary for an employee */ public void updateEmployee(Integer EmployeeID, int salary) { Session session = factory.openSession(); Transaction tx = null; try { tx = session.beginTransaction(); Employee employee = (Employee) session.get(Employee.class, EmployeeID); employee.setSalary(salary); session.update(employee); tx.commit(); } catch (HibernateException e) { if (tx != null) tx.rollback(); e.printStackTrace(); } finally { session.close(); } } /* Method to DELETE an employee from the records */ public void deleteEmployee(Integer EmployeeID) { Session session = factory.openSession(); Transaction tx = null; try { tx = session.beginTransaction(); Employee employee = (Employee) session.get(Employee.class, EmployeeID); session.delete(employee); tx.commit(); } catch (HibernateException e) { if (tx != null) tx.rollback(); e.printStackTrace(); } finally { session.close(); } } }
Main.java
import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; public class Main { public static void main(String[] args) { ManageEmployee ME = new ManageEmployee(); /* Add few employee records in database */ Integer empID1 = ME.addEmployee("Zara", "Ali", 1000); Integer empID2 = ME.addEmployee("Daisy", "Das", 5000); Integer empID3 = ME.addEmployee("John", "Paul", 10000); /* List down all the employees */ ME.listEmployees(); /* Update employee's records */ ME.updateEmployee(empID1, 5000); /* Delete an employee from the database */ ME.deleteEmployee(empID2); /* List down new list of the employees */ ME.listEmployees(); } }
References
https://github.com/mhdr/HibernateSamples/tree/master/002_CRUD