Java/JPA/Query Parameter

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Date Type Parameter

   <source lang="java">

File: Main.java import java.util.Collection; import java.util.Date; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; import javax.persistence.Persistence; public class Main {

 public static void main(String[] a) throws Exception {
   JPAUtil util = new JPAUtil();
   EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
   EntityManager em = emf.createEntityManager();
   ProfessorService service = new ProfessorService(em);
   em.getTransaction().begin();
   service.findProfessorsHiredDuringPeriod(new Date(), new Date());
   
   
   util.checkData("select * from Professor");
   util.checkData("select * from Department");
   
   em.getTransaction().rumit();
   em.close();
   emf.close();
 }

}

File: Department.java

import java.util.ArrayList; import java.util.Collection; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.OneToMany; @Entity public class Department {

   @Id
   private int id;
   private String name;
   @OneToMany(mappedBy="department")
   private Collection<Professor> employees;
   public Department() {
       employees = new ArrayList<Professor>();
   }
   
   public int getId() {
       return id;
   }
   
   public String getName() {
       return name;
   }
   
   public Collection<Professor> getProfessors() {
       return employees;
   }
   public String toString() {
       return "Department no: " + getId() + 
              ", name: " + getName();
   }

}

File: JPAUtil.java import java.io.Reader; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.Statement; public class JPAUtil {

 Statement st;
 
 public JPAUtil() throws Exception{
   Class.forName("org.hsqldb.jdbcDriver");
   System.out.println("Driver Loaded.");
   String url = "jdbc:hsqldb:data/tutorial";
   Connection conn = DriverManager.getConnection(url, "sa", "");
   System.out.println("Got Connection.");
   st = conn.createStatement();
 }
 public void executeSQLCommand(String sql) throws Exception {
   st.executeUpdate(sql);
 }
 public void checkData(String sql) throws Exception {
   ResultSet rs = st.executeQuery(sql);
   ResultSetMetaData metadata = rs.getMetaData();
   for (int i = 0; i < metadata.getColumnCount(); i++) {
     System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
   }
   System.out.println("\n----------------------------------");
   while (rs.next()) {
     for (int i = 0; i < metadata.getColumnCount(); i++) {
       Object value = rs.getObject(i + 1);
       if (value == null) {
         System.out.print("\t       ");
       } else {
         System.out.print("\t"+value.toString().trim());
       }
     }
     System.out.println("");
   }
 }

}

File: Professor.java

import java.util.ArrayList; import java.util.Collection; import java.util.Date; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.ManyToMany; import javax.persistence.ManyToOne; import javax.persistence.NamedQueries; import javax.persistence.NamedQuery; import javax.persistence.OneToMany; import javax.persistence.Temporal; import javax.persistence.TemporalType; @Entity public class Professor {

   @Id
   private int id;
   private String name;
   private long salary;
   @Temporal(TemporalType.DATE)
   private Date startDate;
   
   @ManyToOne
   private Professor manager;
   
   @OneToMany(mappedBy="manager")
   private Collection<Professor> directs;
   @ManyToOne
   private Department department;
   
   @ManyToMany 
   private Collection<Project> projects;
   public Professor() {
       projects = new ArrayList<Project>();
       directs = new ArrayList<Professor>();
   }
   public int getId() {
       return id;
   }
   
   public String getName() {
       return name;
   }
   public long getSalary() {
       return salary;
   }
   public Date getStartDate() {
       return startDate;
   }
   
   public Department getDepartment() {
       return department;
   }
   
   public Collection<Professor> getDirects() {
       return directs;
   }
   
   public Professor getManager() {
       return manager;
   }
   public Collection<Project> getProjects() {
       return projects;
   }
   
   public String toString() {
       return "Professor " + getId() + 
              ": name: " + getName() +
              ", salary: " + getSalary() +
              ", dept: " + ((getDepartment() == null) ? null : getDepartment().getName());
   }

}

File: ProfessorService.java import java.util.Collection; import java.util.Date; import javax.persistence.EntityManager; import javax.persistence.TemporalType; public class ProfessorService {

 protected EntityManager em;
 public ProfessorService(EntityManager em) {
   this.em = em;
 }
 public Collection<Professor> findProfessorsHiredDuringPeriod(Date start, Date end) {
   return (Collection<Professor>) 
       em.createQuery("SELECT e " +
                      "FROM Professor e " +
                      "WHERE e.startDate BETWEEN :start AND :end")
         .setParameter("start", start, TemporalType.DATE)
         .setParameter("end", end, TemporalType.DATE)
         .getResultList();

} }

File: Project.java

import java.util.ArrayList; import java.util.Collection; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.ManyToMany; @Entity public class Project {

   @Id
   protected int id;
   protected String name;
   @ManyToMany(mappedBy="projects")
   private Collection<Professor> employees;
   public Project() {
       employees = new ArrayList<Professor>();
   }
   public int getId() {
       return id;
   }
   
   public String getName() {
       return name;
   }
   
   public Collection<Professor> getProfessors() {
       return employees;
   }
   
   public String toString() {
       return "Project id: " + getId() + ", name: " + getName();
   }

}

File: persistence.xml <persistence xmlns="http://java.sun.ru/xml/ns/persistence"

            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/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>


      </source>
   
  
 
  



Query With Parameter

   <source lang="java">

File: Professor.java

import javax.persistence.Entity; import javax.persistence.Id; @Entity public class Professor {

   @Id
   private int id;
   private String name;
   private long salary;
   public Professor() {}
   public Professor(int id) {
       this.id = id;
   }
   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 long getSalary() {
       return salary;
   }
   public void setSalary(long salary) {
       this.salary = salary;
   }
   
   public String toString() {
       return "Professor id: " + getId() + " name: " + getName() + " salary: " + getSalary();
   }

}

File: ProfessorService.java import java.util.Collection; import javax.persistence.EntityManager; import javax.persistence.Query; public class ProfessorService {

 protected EntityManager em;
 public ProfessorService(EntityManager em) {
   this.em = em;
 }
 public Professor createProfessor(int id, String name, long salary) {
   Professor emp = new Professor(id);
   emp.setName(name);
   emp.setSalary(salary);
   em.persist(emp);
   return emp;
 }
 public void removeProfessor(int id) {
   Professor emp = findProfessor(id);
   if (emp != null) {
     em.remove(emp);
   }
 }
 public Professor raiseProfessorSalary(int id, long raise) {
   Professor emp = em.find(Professor.class, id);
   if (emp != null) {
     emp.setSalary(emp.getSalary() + raise);
   }
   return emp;
 }
 public Professor findProfessor(int id) {
   return em.find(Professor.class, id);
 }
 public Collection<Professor> findAllProfessors() {
   Query query = em.createQuery("SELECT e FROM Professor e");
   return (Collection<Professor>) query.getResultList();
 }

}

File: JPAUtil.java import java.io.Reader; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.Statement; public class JPAUtil {

 Statement st;
 
 public JPAUtil() throws Exception{
   Class.forName("org.hsqldb.jdbcDriver");
   System.out.println("Driver Loaded.");
   String url = "jdbc:hsqldb:data/tutorial";
   Connection conn = DriverManager.getConnection(url, "sa", "");
   System.out.println("Got Connection.");
   st = conn.createStatement();
 }
 public void executeSQLCommand(String sql) throws Exception {
   st.executeUpdate(sql);
 }
 public void checkData(String sql) throws Exception {
   ResultSet rs = st.executeQuery(sql);
   ResultSetMetaData metadata = rs.getMetaData();
   for (int i = 0; i < metadata.getColumnCount(); i++) {
     System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
   }
   System.out.println("\n----------------------------------");
   while (rs.next()) {
     for (int i = 0; i < metadata.getColumnCount(); i++) {
       Object value = rs.getObject(i + 1);
       if (value == null) {
         System.out.print("\t       ");
       } else {
         System.out.print("\t"+value.toString().trim());
       }
     }
     System.out.println("");
   }
 }

}

File: Main.java import java.util.Collection; import java.util.Iterator; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; import javax.persistence.Persistence; public class Main {

 public static void main(String[] a) throws Exception {
   JPAUtil util = new JPAUtil();
   EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
   EntityManager em = emf.createEntityManager();
   ProfessorService service = new ProfessorService(em);
   em.getTransaction().begin();
   Professor emp = service.createProfessor(1, "name", 100);
   emp = service.createProfessor(2, "name 2", 100);
   Integer id = 0;
   Collection expired = em.createQuery("SELECT u FROM Professor u WHERE u.id > ?1").setParameter(1,
       id).getResultList();
   for (Iterator i = expired.iterator(); i.hasNext();) {
     Professor u = (Professor) i.next();
     System.out.println("Expiring password for " + u.getName());
   }
   for (Object o : em.createQuery("SELECT u FROM Professor u").getResultList()) {
     System.out.println(o);
   }
   util.checkData("select * from Professor");
   em.getTransaction().rumit();
   em.close();
   emf.close();
 }

}


File: persistence.xml <persistence xmlns="http://java.sun.ru/xml/ns/persistence"

            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/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>

      </source>
   
  
 
  



Use Entity As Query Parameter

   <source lang="java">


File: Department.java

import java.util.ArrayList; import java.util.Collection; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.OneToMany; @Entity public class Department {

   @Id
   private int id;
   private String name;
   @OneToMany(mappedBy="department")
   private Collection<Professor> employees;
   public Department() {
       employees = new ArrayList<Professor>();
   }
   
   public int getId() {
       return id;
   }
   
   public String getName() {
       return name;
   }
   
   public Collection<Professor> getProfessors() {
       return employees;
   }
   public String toString() {
       return "Department no: " + getId() + 
              ", name: " + getName();
   }

}

File: Professor.java

import java.util.ArrayList; import java.util.Collection; import java.util.Date; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.ManyToMany; import javax.persistence.ManyToOne; import javax.persistence.NamedQueries; import javax.persistence.NamedQuery; import javax.persistence.OneToMany; import javax.persistence.Temporal; import javax.persistence.TemporalType; @Entity @NamedQueries({

 @NamedQuery(name="findProfessorsAboveSal",
             query="SELECT e " +
                   "FROM Professor e " +
                   "WHERE e.department = :dept AND " +
                   "      e.salary > :sal")

}) public class Professor {

   @Id
   private int id;
   private String name;
   private long salary;
   @Temporal(TemporalType.DATE)
   private Date startDate;
   
   @ManyToOne
   private Professor manager;
   
   @OneToMany(mappedBy="manager")
   private Collection<Professor> directs;
   @ManyToOne
   private Department department;
   
   @ManyToMany 
   private Collection<Project> projects;
   public Professor() {
       projects = new ArrayList<Project>();
       directs = new ArrayList<Professor>();
   }
   public int getId() {
       return id;
   }
   
   public String getName() {
       return name;
   }
   public long getSalary() {
       return salary;
   }
   public Date getStartDate() {
       return startDate;
   }
   
   public Department getDepartment() {
       return department;
   }
   
   public Collection<Professor> getDirects() {
       return directs;
   }
   
   public Professor getManager() {
       return manager;
   }
   public Collection<Project> getProjects() {
       return projects;
   }
   
   public String toString() {
       return "Professor " + getId() + 
              ": name: " + getName() +
              ", salary: " + getSalary() +
              ", dept: " + ((getDepartment() == null) ? null : getDepartment().getName());
   }

}

File: ProfessorService.java import java.util.Collection; import javax.persistence.EntityManager; import javax.persistence.NoResultException; public class ProfessorService {

 protected EntityManager em;
 public ProfessorService(EntityManager em) {
   this.em = em;
 }
 public Collection<Professor> findProfessorsAboveSal(Department dept, long minSal) {
     return (Collection<Professor>) em.createNamedQuery("findProfessorsAboveSal")
                                     .setParameter("dept", dept)
                                     .setParameter("sal", minSal)
                                     .getResultList();
 }

}

File: Project.java

import java.util.ArrayList; import java.util.Collection; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.ManyToMany; @Entity public class Project {

   @Id
   protected int id;
   protected String name;
   @ManyToMany(mappedBy="projects")
   private Collection<Professor> employees;
   public Project() {
       employees = new ArrayList<Professor>();
   }
   public int getId() {
       return id;
   }
   
   public String getName() {
       return name;
   }
   
   public Collection<Professor> getProfessors() {
       return employees;
   }
   
   public String toString() {
       return "Project id: " + getId() + ", name: " + getName();
   }

}

File: Main.java import java.util.Collection; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; import javax.persistence.Persistence; public class Main {

 public static void main(String[] a) throws Exception {
   JPAUtil util = new JPAUtil();
   EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
   EntityManager em = emf.createEntityManager();
   ProfessorService service = new ProfessorService(em);
   em.getTransaction().begin();


   util.checkData("select * from Professor");
   util.checkData("select * from Department");
   
   em.getTransaction().rumit();
   em.close();
   emf.close();
 }

}

File: JPAUtil.java import java.io.Reader; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.Statement; public class JPAUtil {

 Statement st;
 
 public JPAUtil() throws Exception{
   Class.forName("org.hsqldb.jdbcDriver");
   System.out.println("Driver Loaded.");
   String url = "jdbc:hsqldb:data/tutorial";
   Connection conn = DriverManager.getConnection(url, "sa", "");
   System.out.println("Got Connection.");
   st = conn.createStatement();
 }
 public void executeSQLCommand(String sql) throws Exception {
   st.executeUpdate(sql);
 }
 public void checkData(String sql) throws Exception {
   ResultSet rs = st.executeQuery(sql);
   ResultSetMetaData metadata = rs.getMetaData();
   for (int i = 0; i < metadata.getColumnCount(); i++) {
     System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
   }
   System.out.println("\n----------------------------------");
   while (rs.next()) {
     for (int i = 0; i < metadata.getColumnCount(); i++) {
       Object value = rs.getObject(i + 1);
       if (value == null) {
         System.out.print("\t       ");
       } else {
         System.out.print("\t"+value.toString().trim());
       }
     }
     System.out.println("");
   }
 }

}


File: persistence.xml <persistence xmlns="http://java.sun.ru/xml/ns/persistence"

            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/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>


      </source>