8:00 – 6:00 VTX

• No MIT video today. Went out and saw Star Wars. Fun! Need to see it again when the crowds thin out in an IMAX theater.
• Copied some stunt data into the hibernate_test db.
• Ran the code that set up the session and connected to the (empty) db. No exceptions, so I think it’s working this time…
• IDE is tracking annotations. The names in the annotation class need to be the same as the table and element names or there is an error 
• Ok, reading and writing into the db. Now to clean it up and separate elements;
• Here’s the current cleaned up version. Still need to create the table more properly.

  package com.philfeldman.mains;
  
  import com.philfeldman.mappings.Employee;
  import org.hibernate.HibernateException;
  import org.hibernate.Query;
  import org.hibernate.Session;
  import org.hibernate.SessionFactory;
  import org.hibernate.cfg.Configuration;
  import org.hibernate.metadata.ClassMetadata;
  import org.hibernate.service.ServiceRegistry;
  import org.hibernate.service.ServiceRegistryBuilder;
  
  import java.util.Map;
  import java.util.Random;
  
  /**
   * Created by philip.feldman on 12/21/2015.
   *
   * A simple test program that will read and write from a table in a database. In MySql, the
   * table is in the form:
           CREATE TABLE employee (
           id int(11) NOT NULL AUTO_INCREMENT,
           name varchar(50) DEFAULT NULL,
           PRIMARY KEY (id)
   ) ;
   */
  public class EmployeeTest {
      private SessionFactory sessionFactory;
      private ServiceRegistry serviceRegistry;
      private Session session;
      private Random rand;
  
      public EmployeeTest()throws ExceptionInInitializerError{
          this.rand = new Random();
          try {
              Configuration config = new Configuration();
              config.configure("hibernate.cfg.xml");
  
              this.serviceRegistry = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();
              this.sessionFactory = config.buildSessionFactory(serviceRegistry);
              this.session = this.sessionFactory.openSession();
          } catch (Throwable ex) {
              throw new ExceptionInInitializerError(ex);
          }
      }
  
      public void closeSession(){
          this.session.close();
      }
  
      public void printAllEntityNames(){
          System.out.println("querying all the managed entities...");
          final Map metadataMap = this.session.getSessionFactory().getAllClassMetadata();
          System.out.println("There are [" + metadataMap.keySet().size() + "] members in the set");
          for (Object key : metadataMap.keySet()) {
              System.out.println("key = ["+key.toString()+"]");
          }
      }
  
      public void printAllEmployees(){
          String key = Employee.class.getCanonicalName();
          final Map metadataMap = this.session.getSessionFactory().getAllClassMetadata();
          final ClassMetadata classMetadata = (ClassMetadata) metadataMap.get(key);
          final String entityName = classMetadata.getEntityName();
          final Query query = session.createQuery("from " + entityName);
          System.out.println("executing: " + query.getQueryString());
          for (Object o : query.list()) {
              Employee e = (Employee) o;
              System.out.println("  " + e.toString());
          }
      }
  
      public void addRandomEmployee(){
          try {
              session.beginTransaction();
              Employee employee = new Employee();
              employee.setName("rand(" + this.rand.nextInt(100) + ")");
              session.save(employee);
              session.getTransaction().commit();
          }catch (HibernateException e){
              session.getTransaction().rollback();
          }
      }
  
      public static void main(String[] args){
          try {
              //System.out.println("Employee.class.getCanonicalName: "+Employee.class.getCanonicalName());
              /***/
              EmployeeTest et = new EmployeeTest();
              et.printAllEntityNames();
              et.printAllEmployees();
              et.addRandomEmployee();
              et.closeSession();
               /***/
          }catch (Exception e){
              e.printStackTrace();
          }
  
      }
  }