[mm2ha]

Hi, I am creating a webapp, using myeclipse ide, hibernate 3.0(with hsqldb database) and struts 1.2. I am trying to do a test for the database settings, so that I can be sure that it will work later. However, when I do session.save, it does not save into the database permanently(what I want it to do), but it is there only until the end of the java program(when I list the things in database during one run, it shows it, but then when I check the database, it is not there). But when I debug that program, it will add it to the database, but not everytime either, its really weird. What can be wrong? the codes follow

SQL for of the table:

TABLE users (
user_id int IDENTITY,
meno varchar(30) not null,
heslo varchar(30) not null,
admin boolean default false,
isloggedin boolean default false,
unique(meno), unique(user_id),
primary key(user_id)
)

code for the actual java application which is being run:

import java.util.Iterator;

import hibernate.HibernateSessionFactory;
import hibernate.Users;


import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

public class UsersTest {
    
    private Session session;
    private Transaction tx;
    
    private void setSession(Session session){
        this.session = session;
    }
    
    private Session getSession(){
        return this.session;
    }
    
    private void createUser(String meno, String heslo){
        System.out.println("Creating user");
        try{
            this.session = HibernateSessionFactory.currentSession();
            tx = session.beginTransaction();
            Users user = new Users();
            user.setMeno(meno);
            user.setHeslo(heslo);
            System.out.println("Created user: " + user.getMeno());
            session.save(user);
            tx.commit();
            session.close();
        } catch (HibernateException e){
            e.printStackTrace();
            if (tx != null)
                try {
                    tx.rollback();
                } catch (HibernateException e1) {
                    System.out.println("rollback not successful");
                }
                
                if (session != null)
                    try {
                        session.close();
                    } catch (HibernateException e2) {
                        System.out.println("session close not successful");
                    }
        }
    }
    
    private void listUsers(){
        System.out.println("listing users");
        this.session = HibernateSessionFactory.currentSession();
        Query query;
        try{
            tx = session.beginTransaction();
            query = session.createQuery("select u from Users as u");
            for (Iterator iter = query.iterate(); iter.hasNext();){
                Users user = (Users) iter.next();
                System.out.println("Meno: " + user.getMeno() + ", heslo: " + user.getHeslo());
            }
            tx.commit();
            session.close();
        }catch (HibernateException e){
            e.printStackTrace();
            if (tx != null)
                try {
                    tx.rollback();
                } catch (HibernateException e1) {
                    System.out.println("rollback not successful");
                }
                
                if (session != null)
                    try {
                        session.close();
                    } catch (HibernateException e2) {
                        System.out.println("session close not successful");
                    }
        }
    }
    
    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        UsersTest test = new UsersTest();
        test.createUser("adrian","ado");
        test.listUsers();
        
    }
    
}

Hibernate.cfg.xml:

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<!-- Generated by MyEclipse Hibernate Tools.                   -->
<hibernate-configuration>

<session-factory>
    <property name="myeclipse.connection.profile">datalock</property>
    <property name="connection.url">
        jdbc:hsqldb:c:\hsqldb\databases\datalock
    </property>
    <property name="connection.username">sa</property>
    <property name="connection.password"></property>
    <property name="connection.driver_class">
        org.hsqldb.jdbcDriver
    </property>
    <property name="dialect">org.hibernate.dialect.HSQLDialect</property>
    <mapping resource="hibernate/Users.hbm.xml" />


</session-factory>

</hibernate-configuration>

Users.hbm.xml:

<?xml version="1.0" encoding='UTF-8'?>
<!DOCTYPE hibernate-mapping PUBLIC
                            "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
                            "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >

<!-- DO NOT EDIT: This is a generated file that is synchronized -->
<!-- by MyEclipse Hibernate tool integration.                   -->
<!-- Created Wed Aug 03 17:12:49 CEST 2005                         -->
<hibernate-mapping package="hibernate">

    <class name="Users" table="USERS">
        <id name="userId" column="USER_ID" type="java.lang.Integer">
            <generator class="native"/>
        </id>
 
        <property name="meno" column="MENO" type="java.lang.String"  not-null="true" />
        <property name="heslo" column="HESLO" type="java.lang.String"  not-null="true" />
        <property name="admin" column="ADMIN" type="java.lang.Boolean" />
        <property name="isloggedin" column="ISLOGGEDIN" type="java.lang.Boolean" />
    </class>
    
</hibernate-mapping>

and Users.java created by myeclipse:

/*
 * WARNING: DO NOT EDIT THIS FILE. This is a generated file that is synchronized
 * by MyEclipse Hibernate tool integration.
 *
 * Created Wed Aug 03 17:12:50 CEST 2005 by MyEclipse Hibernate Tool.
 */
package hibernate;

import java.io.Serializable;

/**
 * A class that represents a row in the USERS table. 
 * You can customize the behavior of this class by editing the class, {@link Users()}.
 * WARNING: DO NOT EDIT THIS FILE. This is a generated file that is synchronized * by MyEclipse Hibernate tool integration.
 */
public abstract class AbstractUsers 
    implements Serializable
{
    /** The cached hash code value for this instance.  Settting to 0 triggers re-calculation. */
    private int hashValue = 0;

    /** The composite primary key value. */
    private java.lang.Integer userId;

    /** The value of the simple meno property. */
    private java.lang.String meno;

    /** The value of the simple heslo property. */
    private java.lang.String heslo;

    /** The value of the simple admin property. */
    private java.lang.Boolean admin;

    /** The value of the simple isloggedin property. */
    private java.lang.Boolean isloggedin;

    /**
     * Simple constructor of AbstractUsers instances.
     */
    public AbstractUsers()
    {
    }

    /**
     * Constructor of AbstractUsers instances given a simple primary key.
     * @param userId
     */
    public AbstractUsers(java.lang.Integer userId)
    {
        this.setUserId(userId);
    }

    /**
     * Return the simple primary key value that identifies this object.
     * @return java.lang.Integer
     */
    public java.lang.Integer getUserId()
    {
        return userId;
    }

    /**
     * Set the simple primary key value that identifies this object.
     * @param userId
     */
    public void setUserId(java.lang.Integer userId)
    {
        this.hashValue = 0;
        this.userId = userId;
    }

    /**
     * Return the value of the MENO column.
     * @return java.lang.String
     */
    public java.lang.String getMeno()
    {
        return this.meno;
    }

    /**
     * Set the value of the MENO column.
     * @param meno
     */
    public void setMeno(java.lang.String meno)
    {
        this.meno = meno;
    }

    /**
     * Return the value of the HESLO column.
     * @return java.lang.String
     */
    public java.lang.String getHeslo()
    {
        return this.heslo;
    }

    /**
     * Set the value of the HESLO column.
     * @param heslo
     */
    public void setHeslo(java.lang.String heslo)
    {
        this.heslo = heslo;
    }

    /**
     * Return the value of the ADMIN column.
     * @return java.lang.Boolean
     */
    public java.lang.Boolean isAdmin()
    {
        return this.admin;
    }

    /**
     * Set the value of the ADMIN column.
     * @param admin
     */
    public void setAdmin(java.lang.Boolean admin)
    {
        this.admin = admin;
    }

    /**
     * Return the value of the ISLOGGEDIN column.
     * @return java.lang.Boolean
     */
    public java.lang.Boolean isIsloggedin()
    {
        return this.isloggedin;
    }

    /**
     * Set the value of the ISLOGGEDIN column.
     * @param isloggedin
     */
    public void setIsloggedin(java.lang.Boolean isloggedin)
    {
        this.isloggedin = isloggedin;
    }

    /**
     * Implementation of the equals comparison on the basis of equality of the primary key values.
     * @param rhs
     * @return boolean
     */
    public boolean equals(Object rhs)
    {
        if (rhs == null)
            return false;
        if (! (rhs instanceof Users))
            return false;
        Users that = (Users) rhs;
        if (this.getUserId() == null || that.getUserId() == null)
            return false;
        return (this.getUserId().equals(that.getUserId()));
    }

    /**
     * Implementation of the hashCode method conforming to the Bloch pattern with
     * the exception of array properties (these are very unlikely primary key types).
     * @return int
     */
    public int hashCode()
    {
        if (this.hashValue == 0)
        {
            int result = 17;
            int userIdValue = this.getUserId() == null ? 0 : this.getUserId().hashCode();
            result = result * 37 + userIdValue;
            this.hashValue = result;
        }
        return this.hashValue;
    }
}

[Riyad Kalla]

HSQL is an in-memory DB, unless you persist it to disk, it will loose it’s contents when your program exists.

[mm2ha]

Hsqldb can be also a persistent database, if you specify a location where it should be(example:jdbc:hsqldb:c:\hsqldb\databases\datalock), then it is there and you can retrieve it. I have no problem inserting into that database when I am in the database explorer and it holds the values also after I close eclipse. The problem is that the program saves it into the DB only temporarily, or I dont know what it does. But when I have debugged it and stepped thorough it, it added the values correctly, but again not every time I did that. So its really weird.

[Riyad Kalla]

Hmm, I really don’t know why HSQL is behaving this way, I double checked your Hib code and it looks fine, you start your transaction then commit it… AFAIK that’s all you should need to do.

Maybe you can try setting up a local MySQL install and seeing if the behavior normalizes? If it does, then it’s likely just a setup issue with HSQL.

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