First Hibernate example, Hibernate getting started

No need to explain about Hibernate as it is well known ORM tool.

One simple running example I am going to explain here. Just you follow step by step you would be able to run your first Hibernate example. This example will contect mysql database.


1. Download all below jar file.

mysql-connector-java-3.1.12-bin.jar
commons-logging-1.1.jar
dom4j-1.6.1.jar
commons-collections-3.2.jar
log4j-1.2.15.jar
slf4j-api-1.6.0.jar
slf4j-log4j12-1.6.0.jar
slf4j-simple-1.6.0.jar
javassist-3.3.jar
jta-1.0.1B.jar
hibernate-commons-annotations-3.1.0.GA.jar
hibernate-annotations-3.1beta8.jar
hibernate-core-3.3.1.GA.jar
antlr-2.7.5H3.jar
javassist-3.3.jar

2. First create one project in Eclipse say FirstHibernate and add these jar file into that project.

3. Create these below three file into your project src folder.

hibernate.cfg.xml

Student.hbm.xml
Student.java
Client.java

create one student table in database. In our example database name is sumandb.


CREATE TABLE student (
id int(11) NOT NULL,
name varchar(90) default NULL,
marks int(11) default NULL,
PRIMARY KEY (id)
)

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="connection.url">jdbc:mysql://localhost/sumandb</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="connection.username">root</property>
<property name="connection.password">mysql</property>
<property name="transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
<!-- this will show us all sql statements -->
<property name="hibernate.show_sql">true</property>
<!-- mapping files -->
<mapping resource="Student.hbm.xml" />
</session-factory>
</hibernate-configuration>

Student.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" >
<hibernate-mapping>
<class name="Student" table="student">
<id name="studentId" column="id">
<generator class="increment" />
</id>
<!-- Both property are optional here as property name and column name are same -->
<property name="name" column="name" />
<property name="marks" column="marks" />
</class>
</hibernate-mapping>

Student.java
/**
* @author Binod Suman
*/

public class Student {
private int studentId;
private String name;
private int marks;

public Student() { }


public Student(int studentId, String name, int marks) {
this.studentId = studentId;
this.name = name;
this.marks = marks;
}


public Student(String name, int marks) {
this.name = name;
this.marks = marks;
}






public int getStudentId() {return studentId;}
public void setStudentId(int studentId) {this.studentId = studentId;}
public String getName() {return name;}
public void setName(String name) {this.name = name;}
public int getMarks() {return marks;}
public void setMarks(int marks) {this.marks = marks;}

}


Client.java
import java.util.List;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
/*
* @author Binod Suman
*/


public class Client {
public static void main(String[] args) {
Client test = new Client();
test.saveStudent();
// test.showAllStudent();
// test.searchStudent(2);
}


public void saveStudent(){
System.out.println("Inserting new Student record ...... ");
SessionFactory sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
Session session =sessionFactory.openSession();
Transaction transaction = session.beginTransaction();
Student student = new Student("Binod Suman",99);
session.save(student);
transaction.commit();
session.flush();
session.close();
System.out.println("Student record has been successfully saved ");
}

public void showAllStudent(){
SessionFactory sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
Session session =sessionFactory.openSession();
List students = session.createQuery("from Student").list();

for(Student student : students){
System.out.println("Student Name :: "+student.getName());
System.out.println("Student Roll :: "+student.getStudentId());
System.out.println("Student Marks :: "+student.getMarks());
System.out.println("************************");
}

}

public void searchStudent(int id){
SessionFactory sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
Session session =sessionFactory.openSession();
Student student = (Student)session.load(Student.class, id);
System.out.println("Student Name :: "+student.getName());
System.out.println("Student Roll :: "+student.getStudentId());
System.out.println("Student Marks :: "+student.getMarks());
}

}


Even if you are getting below exceptions, just you follow the above steps and add proper version of jar file, all  your below exception be removed.

Exception in thread "main" java.lang.NoSuchMethodError: org.slf4j.Logger.isTraceEnabled()Z


Exception in thread "main" java.lang.IllegalAccessError: tried to access field org.hibernate.cfg.Configuration.xmlHelper from class org.hibernate.cfg.AnnotationConfiguration

Exception in thread "main" java.lang.NoSuchFieldError: sqlResultSetMappings

That's it ........... :)

Thanks ..... :)