3 Replies Latest reply on Mar 12, 2009 8:46 PM by manish shrestha

    EJB3 entity bean query always returns null

    manish shrestha Newbie

      I have had this problem for a month now. I am trying to execute a JPA query from a session bean, and everytime it returns only null. Other functionalities of the entity bean like persist() works, and stores database. What am i doing wrong here. My code is attached below:


      import javax.ejb.Stateless;
      import javax.persistence.EntityManager;
      import javax.persistence.PersistenceContext;
      import javax.persistence.Query;

      @Stateless

      public class LoginBean implements LoginBeanRemote, LoginBeanLocal {

      public LoginBean() {

      }

      @PersistenceContext(unitName="CustomerUnit")
      EntityManager manager;

      public String validateLogin(String userName, String password)
      {
      try
      {
      Query q1 = manager.createQuery("SELECT c FROM Customer c WHERE c.userName = :username AND c.password = :password ");
      q1.setParameter("username", userName);
      q1.setParameter("password", password);
      System.out.println(q1.getSingleResult());

      }
      catch(Exception e)
      {
      e.printStackTrace();
      }

      return "loginUser";
      }
      }

        • 1. Re: EJB3 entity bean query always returns null
          manish shrestha Newbie

           

          "mxshrestha" wrote:
          I have had this problem for a month now. I am trying to execute a JPA query from a session bean, and everytime it returns only null. Other functionalities of the entity bean like persist() works, and stores in database. What am i doing wrong here. My code is attached below:

          import javax.ejb.Stateless;
          import javax.persistence.EntityManager;
          import javax.persistence.PersistenceContext;
          import javax.persistence.Query;

          @Stateless
          public class LoginBean implements LoginBeanRemote, LoginBeanLocal {

          public LoginBean() {

          }

          @PersistenceContext(unitName="CustomerUnit")
          EntityManager manager;

          public String validateLogin(String userName, String password)
          {
          try
          {
          Query q1 = manager.createQuery("SELECT c FROM Customer c WHERE c.userName = :username AND c.password = :password ");
          q1.setParameter("username", userName);
          q1.setParameter("password", password);
          System.out.println(q1.getSingleResult());

          }
          catch(Exception e)
          {
          e.printStackTrace();
          }

          return "loginUser";
          }
          }

          Also, my entity bean and persistence.xml is included. I am using oracle 10g.

          package com.entities;

          import java.io.Serializable;
          import java.sql.Date;

          import javax.persistence.*;

          /**
          * Entity implementation class for Entity: Customer
          *
          */
          @Entity
          @Table(name="Customer")
          @IdClass(com.entities.Customer.class)
          public class Customer implements Serializable {


          private static final long serialVersionUID = 1L;
          private String id;
          private String userName;
          private String password;
          private String firstName;
          private String middleInitial;
          private String lastName;
          private String email;
          private Date birthDate;
          private String homePhoneNo;
          private String cellPhoneNo;
          private Date lastLogin;

          public Customer() {
          super();
          }

          public Customer(String id, String userName, String password, String firstName, String middleInitial,
          String lastName, String email, Date birthDate, String homePhoneNo, String cellPhoneNo,
          Date lastLogin)
          {
          setId(id);
          setUserName(userName);
          setPassword(password);
          setFirstName(firstName);
          setMiddleInitial(middleInitial);
          setLastName(lastName);
          setEmail(email);
          setBirthDate(birthDate);
          setHomePhoneNo(homePhoneNo);
          setCellPhoneNo(cellPhoneNo);
          setLastLogin(lastLogin);
          }

          @Id
          @Column(name="CUSTID")
          public String getId() {
          return id;
          }

          public void setId(String id) {
          this.id = id;
          }

          @Column(name="USERNAME")
          public String getUserName() {
          return userName;
          }

          public void setUserName(String userName) {
          this.userName = userName;
          }

          @Column(name="PASSWORD")
          public String getPassword() {
          return password;
          }

          public void setPassword(String password) {
          this.password = password;
          }

          @Column(name="FNAME")
          public String getFirstName() {
          return firstName;
          }

          public void setFirstName(String firstName) {
          this.firstName = firstName;
          }

          @Column(name="MI")
          public String getMiddleInitial() {
          return middleInitial;
          }

          public void setMiddleInitial(String middleInitial) {
          this.middleInitial = middleInitial;
          }

          @Column(name="LNAME")
          public String getLastName() {
          return lastName;
          }

          public void setLastName(String lastName) {
          this.lastName = lastName;
          }

          @Column(name="EMAIL")
          public String getEmail() {
          return email;
          }

          public void setEmail(String email) {
          this.email = email;
          }

          @Column(name="DOB")
          public Date getBirthDate() {
          return birthDate;
          }

          public void setBirthDate(Date birthDate) {
          this.birthDate = birthDate;
          }

          @Column(name="HOMEPHONENO")
          public String getHomePhoneNo() {
          return homePhoneNo;
          }

          public void setHomePhoneNo(String homePhoneNo) {
          this.homePhoneNo = homePhoneNo;
          }

          @Column(name="CELLPHONE")
          public String getCellPhoneNo() {
          return cellPhoneNo;
          }

          public void setCellPhoneNo(String cellPhoneNo) {
          this.cellPhoneNo = cellPhoneNo;
          }

          @Column(name="LASTLOGIN")
          public Date getLastLogin() {
          return lastLogin;
          }

          public void setLastLogin(Date lastLogin) {
          this.lastLogin = lastLogin;
          }
          }


          persistence:

          <?xml version="1.0" encoding="UTF-8"?>
          <persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
          <persistence-unit name="CustomerUnit" transaction-type="JTA">
          <jta-data-source>java:/OracleDS</jta-data-source>
          <class>com.entities.Customer</class>
          <properties>
          <property name="hibernate.show_sql" value="true"/>
          <property name="hibernate.format_sql" value="true"/>
          <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect"/>
          <property name="hibernate.hbm2ddl.auto" value="validate"/>
          </properties>
          </persistence-unit>
          </persistence>



          • 2. Re: EJB3 entity bean query always returns null
            jaikiran pai Master

             

            Query q1 = manager.createQuery("SELECT c FROM Customer c WHERE c.userName = :username AND c.password = :password ");
            q1.setParameter("username", userName);
            q1.setParameter("password", password);
            System.out.println(q1.getSingleResult());


            Are you sure the database has an record for this username and password? And are you sure its not case-sensitive?

            • 3. Re: EJB3 entity bean query always returns null
              manish shrestha Newbie

              Yes, I am sure the database exists in the system, and even when i hard code the user name and the password, the query returns null. The database system i am using is oracle 10g and as far as i know it is not case sensitive. Do you think it has anything to do with my persistence.xml file and if not what is the problem???