Java Tutorial/Hibernate/Query by Example

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QBE Advanced Criteria

File: Main.java



import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.criterion.Example;
public class Main {
  public static void main(String[] args) throws Exception {
    HibernateUtil hibernateUtil = new HibernateUtil();
    hibernateUtil
        .executeSQLCommand("create table Product(id int, name varchar, description varchar, price decimal(6,2), supplierid int)");
     
    hibernateUtil
    .executeSQLCommand("create table Supplier (id int , name varchar)");
    hibernateUtil
    .executeSQLCommand("create table Software(id int, name varchar, description varchar, price decimal(6,2), supplierid int, version varchar)");
    
    Session session = hibernateUtil.getSession();
    Supplier superCorp = new Supplier();
    superCorp.setName("Supplier1");
    session.save(superCorp);
    
    Supplier megaInc = new Supplier();
    megaInc.setName("Supplier2");
    session.save(megaInc);        
    Product mouse = new Product("Product1","first product", 20.0);
    mouse.setSupplier(superCorp);
    superCorp.getProducts().add(mouse);
    session.flush();
    Product mouse2 = new Product("Product2","second product", 22.0);
    mouse2.setSupplier(superCorp);
    superCorp.getProducts().add(mouse2);        
    
    Product keyboard = new Product("Product3", "third product", 30.0);
    keyboard.setSupplier(megaInc);
    megaInc.getProducts().add(keyboard);
    Software webBrowser = new Software("Web Browser","new browser", 75.0, "2.0");
    webBrowser.setSupplier(superCorp);
    superCorp.getProducts().add(webBrowser);
    Software email = new Software("Email","email client", 49.99, "4.1 Edition");
    email.setSupplier(megaInc);
    megaInc.getProducts().add(email);    
    session.flush();
    
    
    Criteria prdCrit = session.createCriteria(Product.class);
    Product product = new Product();
    product.setName("P%");
    Example prdExample = Example.create(product);
    prdExample.excludeProperty("price");
    prdExample.enableLike();
    Criteria suppCrit = prdCrit.createCriteria("supplier");
    Supplier supplier = new Supplier();
    supplier.setName("Supplier2");
    suppCrit.add(Example.create(supplier));
    prdCrit.add(prdExample);
    List results = prdCrit.list();

    System.out.println(results);
    
    session.close();
    hibernateUtil.checkData("select * from Product");
    hibernateUtil.checkData("select * from Software");
    hibernateUtil.checkData("select * from Supplier");
  }
}





QBE Criteria: Not Null Or Zero

File: Main.java



import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.criterion.Example;
public class Main {
  public static void main(String[] args) throws Exception {
    HibernateUtil hibernateUtil = new HibernateUtil();
    hibernateUtil
        .executeSQLCommand("create table Product(id int, name varchar, description varchar, price decimal(6,2), supplierid int)");
     
    hibernateUtil
    .executeSQLCommand("create table Supplier (id int , name varchar)");
    hibernateUtil
    .executeSQLCommand("create table Software(id int, name varchar, description varchar, price decimal(6,2), supplierid int, version varchar)");
    
    Session session = hibernateUtil.getSession();
    Supplier superCorp = new Supplier();
    superCorp.setName("Supplier1");
    session.save(superCorp);
    
    Supplier megaInc = new Supplier();
    megaInc.setName("Supplier2");
    session.save(megaInc);        
    Product mouse = new Product("Product1","first product", 20.0);
    mouse.setSupplier(superCorp);
    superCorp.getProducts().add(mouse);
    session.flush();
    Product mouse2 = new Product("Product2","second product", 22.0);
    mouse2.setSupplier(superCorp);
    superCorp.getProducts().add(mouse2);        
    
    Product keyboard = new Product("Product3", "third product", 30.0);
    keyboard.setSupplier(megaInc);
    megaInc.getProducts().add(keyboard);
    Software webBrowser = new Software("Web Browser","new browser", 75.0, "2.0");
    webBrowser.setSupplier(superCorp);
    superCorp.getProducts().add(webBrowser);
    Software email = new Software("Email","email client", 49.99, "4.1 Edition");
    email.setSupplier(megaInc);
    megaInc.getProducts().add(email);    
    session.flush();
    
    
    Criteria crit = session.createCriteria(Product.class);
    Product exampleProduct = new Product();
    exampleProduct.setName("Product3");
    Example example = Example.create(exampleProduct);
    example.excludeZeroes();
    crit.add(example);
    List results = crit.list();

    System.out.println(results);
    
    
    
    session.close();
    hibernateUtil.checkData("select * from Product");
    hibernateUtil.checkData("select * from Software");
    hibernateUtil.checkData("select * from Supplier");
  }
}





Query By Example

File: Main.java



import java.util.Date;
import java.util.Iterator;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.criterion.Example;
public class Main {
  public static void main(String[] args) throws Exception {
    HibernateUtil hibernateUtil = new HibernateUtil();
    hibernateUtil
        .executeSQLCommand("create table survey (id int,name varchar, purchasedate date);");
    Session session = hibernateUtil.getSession();
    Survey survey = new Survey();
    survey.setName("Survey");
    survey.setPurchaseDate(new Date());
    session.save(survey);
    
    survey = new Survey();
    survey.setName("Survey1");
    survey.setPurchaseDate(new Date());    
    session.save(survey);
    
    session.flush();
    
    Criteria crit = session.createCriteria(Survey.class);
    Survey supplier = new Survey();
    supplier.setName("Survey");
    crit.add(Example.create(supplier));
    List results = crit.list();
    Iterator iter = results.iterator();
    while (iter.hasNext()) {
      Survey cd = (Survey) iter.next();
      System.out.println("Result Name:"+cd.getName());
    }
    session.close();
    hibernateUtil.checkData("select * from survey");
  }
}