Java/Hibernate/HQL Select

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HQL: Order

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       String hql = "from Product p where p.price>25.0 order by p.price desc";
       Query query = session.createQuery(hql);
       List results = query.list();
       displayProductsList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displayProductsList(List list){
       Iterator iter = list.iterator();
       if (!iter.hasNext()){
           System.out.println("No products to display.");
           return;
       }
       while (iter.hasNext()) {
           Product product = (Product) iter.next();
           String msg = product.getSupplier().getName() + "\t";
           msg += product.getName() + "\t";
           msg += product.getPrice() + "\t";
           msg += product.getDescription();
           System.out.println(msg);
       }
   }

 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

}

///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}


///////////////////////////////////////////////////////////////////////// <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE hibernate-configuration PUBLIC

   "-//Hibernate/Hibernate Configuration DTD//EN"
   "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

   <session-factory>
       
       <property name="connection.driver_class">org.hsqldb.jdbcDriver</property>
       <property name="connection.url">jdbc:hsqldb:data/tutorial</property>
       <property name="connection.username">sa</property>
       <property name="connection.password"></property>
       
       <property name="connection.pool_size">1</property>
       
       <property name="dialect">org.hibernate.dialect.HSQLDialect</property>
       
       <property name="show_sql">true</property>
       
       <mapping resource="Product.hbm.xml"/>
       <mapping resource="Supplier.hbm.xml"/>
   </session-factory>

</hibernate-configuration>

/////////////////////////////////////////////////////////////////////////


/////////////////////////////////////////////////////////////////////////


      </source>
   
  
 
  



HQL: Order Two Properties

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       String hql = "from Product p order by p.supplier.name asc, p.price asc";
       Query query = session.createQuery(hql);
       List results = query.list();
       displayProductsList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displayProductsList(List list){
       Iterator iter = list.iterator();
       if (!iter.hasNext()){
           System.out.println("No products to display.");
           return;
       }
       while (iter.hasNext()) {
           Product product = (Product) iter.next();
           String msg = product.getSupplier().getName() + "\t";
           msg += product.getName() + "\t";
           msg += product.getPrice() + "\t";
           msg += product.getDescription();
           System.out.println(msg);
       }
   }

 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

}


///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}


      </source>
   
  
 
  



HQL: Paging

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       Query query = session.createQuery("from Product");
       query.setFirstResult(1);
       query.setMaxResults(2);
       List results = query.list();
       displayProductsList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displayProductsList(List list){
       Iterator iter = list.iterator();
       if (!iter.hasNext()){
           System.out.println("No products to display.");
           return;
       }
       while (iter.hasNext()) {
           Product product = (Product) iter.next();
           String msg = product.getSupplier().getName() + "\t";
           msg += product.getName() + "\t";
           msg += product.getPrice() + "\t";
           msg += product.getDescription();
           System.out.println(msg);
       }
   }

 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

}

///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}

      </source>
   
  
 
  



HQL: Projection

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       Query query = session.createQuery("select product.name, product.price from Product product");
       List results = query.list();
       displayObjectsList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displayObjectsList(List list)
   {
       Iterator iter = list.iterator();
       if (!iter.hasNext())
       {
           System.out.println("No objects to display.");
           return;
       }
       while (iter.hasNext())
       {
           System.out.println("New object");
           Object[] obj = (Object[]) iter.next();
           for (int i=0;i<obj.length;i++)
           {
               System.out.println(obj[i]);
           }
           
           
       }
   }       
 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

}

///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}

      </source>
   
  
 
  



Scalar SQL Average

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       String sql = "select avg(product.price) as avgPrice from Product product";
       SQLQuery query = session.createSQLQuery(sql);
       query.addScalar("avgPrice",Hibernate.DOUBLE);
       List results = query.list();
       displayObjectsList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displayObjectsList(List list)
   {
       Iterator iter = list.iterator();
       if (!iter.hasNext())
       {
           System.out.println("No objects to display.");
           return;
       }
       while (iter.hasNext())
       {
           System.out.println("New object");
           Object obj = (Object) iter.next();
           System.out.println(obj);
           
           
       }
   }       
 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

}


///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}


      </source>
   
  
 
  



Select SQL

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       String sql = "select {supplier.*} from Supplier supplier";
           
       SQLQuery query = session.createSQLQuery(sql);
       query.addEntity("supplier", Supplier.class);
       List results = query.list();
       displaySupplierList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displaySupplierList(List list) {
       Iterator iter = list.iterator();
       if (!iter.hasNext()) {
           System.out.println("No suppliers to display.");
           return;
       }        
       while (iter.hasNext()) {
           Supplier supplier = (Supplier) iter.next();
           String msg = supplier.getName();
           System.out.println(msg);
       }
   }

 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

} ///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}


      </source>
   
  
 
  



Unique Result HQL

   <source lang="java">

///////////////////////////////////////////////////////////////////////// import java.util.*; import java.sql.*; import org.hibernate.*; import org.hibernate.criterion.*; public class Main {

 public static void main(String[] args) {
   HibernateUtil.setup("create table Supplier ( id int, name VARCHAR);");
   HibernateUtil.setup("create table Product ( id int, name VARCHAR, description VARCHAR, price double,supplierId int);");
   
   prepareData();
   Session session = HibernateUtil.currentSession();
   
       String hql = "from Product where price>2.0";
       Query query = session.createQuery(hql);
       query.setMaxResults(1);
       Product product = (Product) query.uniqueResult();
       //test for null here if needed
           
       List results = new ArrayList();
       results.add(product);
       displayProductsList(results);
   
   
       HibernateUtil.checkData("select * from Supplier");
       HibernateUtil.checkData("select * from Product");
 }
   static public void displayProductsList(List list){
       Iterator iter = list.iterator();
       if (!iter.hasNext()){
           System.out.println("No products to display.");
           return;
       }
       while (iter.hasNext()) {
           Product product = (Product) iter.next();
           String msg = product.getSupplier().getName() + "\t";
           msg += product.getName() + "\t";
           msg += product.getPrice() + "\t";
           msg += product.getDescription();
           System.out.println(msg);
       }
   }

 private static void prepareData(){
       Session session = HibernateUtil.currentSession();
       Supplier supplier1 = new Supplier();
       supplier1.setName("Supplier Name 1");
       session.save(supplier1);
       
       Supplier supplier2 = new Supplier();
       supplier2.setName("Supplier Name 2");
       session.save(supplier2);        
       
       Product product1 = new Product("Product 1","Name for Product 1", 2.0);
       product1.setSupplier(supplier1);
       supplier1.getProducts().add(product1);
       session.save(product1);
       
       Product product12 = new Product("Product 2","Name for Product 2", 22.0);
       product12.setSupplier(supplier1);
       supplier1.getProducts().add(product12);        
       session.save(product12);
       
       Product product2 = new Product("Product 3", "Name for Product 3", 30.0);
       product2.setSupplier(supplier2);
       supplier2.getProducts().add(product2);
       session.save(product2);
       
       session.flush();
       HibernateUtil.closeSession();
 }

} ///////////////////////////////////////////////////////////////////////// public class Product {

   private int id;
   private Supplier supplier;
   
   private String name;
   private String description;
   private double price;
   
   public Product()
   {
       super();
   }
   
   public Product(String name, String description, double price)
   {
       super();
       this.name = name;
       this.description = description;
       this.price = price;
   }
   
   public String getDescription()
   {
       return description;
   }
   public void setDescription(String description)
   {
       this.description = description;
   }
   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 Supplier getSupplier()
   {
       return supplier;
   }
   public void setSupplier(Supplier supplier)
   {
       this.supplier = supplier;
   }
   
   public double getPrice()
   {
       return price;
   }
   public void setPrice(double price)
   {
       this.price = price;
   }

}


      </source>