Error! connect Hibernate and Postgresql on eclipse

Question

When i run project on eclipse, errors appear:

Jun 08, 2013 6:11:46 AM org.hibernate.annotations.common.Version

INFO: HCANN000001: Hibernate Commons Annotations

{4.0.2.Final} Jun 08, 2013 6:11:46 AM org.hibernate.Version logVersion

INFO: HHH000412: Hibernate Core {4.2.2.Final} Initial SessionFactory

creation failed. java.lang.ExceptionInInitializerError Exception in

thread "main" java.lang.ExceptionInInitializerError at

HibernateUtil.(HibernateUtil.java:13) at

PublisherDAO.addPublisher(PublisherDAO.java:5) at

BookApp.main(BookApp.java:12) Caused by:

java.lang.ExceptionInInitializerError at

org.hibernate.cfg.Configuration.reset(Configuration.java:309) at

org.hibernate.cfg.Configuration.(Configuration.java:275) at

org.hibernate.cfg.Configuration.(Configuration.java:279) at org.hibernate.cfg.AnnotationConfiguration.(AnnotationConfiguration.java:50)

at HibernateUtil.(HibernateUtil.java:8) ... 2 more Caused

by: java.lang.NullPointerException at

org.hibernate.internal.util.ConfigHelper.getResourceAsStream(ConfigHelper.java:170)

at org.hibernate.cfg.Environment.(Environment.java:221) ...

7 more

And code demo:

1)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">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
        <property name="hibernate.connection.password">postgres</property>
        <property name="hibernate.connection.url">jdbc:postgresql://localhost:5432/postgres</property>
        <property name="hibernate.connection.username">postgres</property>
        <property name="hibernate.default_schema">public</property>
        <property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>
        <mapping class="Publisher"/>
    </session-factory>
</hibernate-configuration>

2)BookApp.java

import java.util.*;
import org.hibernate.*;
public class BookApp {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("hello world!");
        PublisherDAO dao=new PublisherDAO();
        dao.addPublisher("003", "Manning", "Mit");
    }

}

3)HibernateUtil.java

import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
public class HibernateUtil {
    private static final SessionFactory sessionFactory;

    static{
        try{
            sessionFactory=new AnnotationConfiguration().configure()
                    .buildSessionFactory();

        }catch(Throwable ex){
            System.err.println("Initial SessionFactory creation failed. "+ex);
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static SessionFactory getSessionFactory(){
        return sessionFactory;
    }
}

4)Publisher.java

import javax.persistence.*;
import static javax.persistence.GenerationType.IDENTITY;

@Entity
@Table(name="publisher")
public class Publisher {
    private String code;
    private String publisher_name;
    private String address;

    @Id
    @Column(name="code")
    @GeneratedValue(strategy=IDENTITY)
    public String getCode() {
        return code;
    }
    public void setCode(String code) {
        this.code = code;
    }

    @Column(name="publisher_name")
    public String getPublisher_name() {
        return publisher_name;
    }
    public void setPublisher_name(String publisher_name) {
        this.publisher_name = publisher_name;
    }

    @Column(name="address")
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
}

5)PublisherDAO.java

import java.util.*;
import org.hibernate.*;
public class PublisherDAO {
    public void addPublisher(String code, String name, String address){
        Session session = HibernateUtil.getSessionFactory().getCurrentSession();
        session.beginTransaction();
        Publisher publisher=new Publisher();
        publisher.setCode(code);
        publisher.setPublisher_name(name);
        publisher.setAddress(address);
        session.save(publisher);
        session.getTransaction().commit();
    }
}

i effort very much, but errors aren't solve.Help me!

Answer 1

They key part seems to be:

java.lang.NullPointerException 
at org.hibernate.internal.util.ConfigHelper.getResourceAsStream(ConfigHelper.java:170)
at org.hibernate.cfg.Environment.(Environment.java:221) 

This suggests that Hibernate is failing to read your configuration. Something is unexpectedly null. Since you didn't specify your exact Hibernate version I couldn't look at the source to say what, so I suggest that you go and do so. See what Hibernate is doing in your exact Hibernate version on line 170 of ConfigHelper.java, which should be within the getResourceAsStream method.

If you're still stuck, add the sources to your debug source path, then run your program under a debugger. Set the debugger to trap on uncaught exceptions (usually the default, but there might be a global exception handler you need to deal with). Or set a breakpoint at the line of interest. Then run the program. When it crashes, look back down the stack to see where it comes into contact with something you wrote.