Hibernate Hello World Program (Hibernate Insert
Query)
Lets have a look at the
first program in
hibernate like saving an object into the database
(don’t
think we are inserting a record into the database
that is the case in
JDBC, in hibernate
we are just
saving an object into
database, means inserting only
) hope you got my
contention, as of now am giving
this as normal console based java application, actually it’s bit
tedious to
set the
class path every time for all the
jar
files but you must know this too.
From the next example i will give all the applications in the
Eclipse
As i told you earlier, these are the files we require to
shape an hibernate program..
Product.java (My POJO class)
Product.hbm.xml (Xml mapping
file )
hibernate.cfg.xml (Xml
configuration file)
- ClientForSave.java (java file to write our hibernate logic)
Product.java:
private int productId;
private String proName;
private double price;
public void setProductId(int productId)
{
this.productId = productId;
}
public int getProductId()
{
return productId;
}
public void setProName(String proName)
{
this.proName = proName;
}
public String getProName()
{
return proName;
}
public void setPrice(double price)
{
this.price = price;
}
public double getPrice()
{
return price;
}
Product.hbm.xml:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="Product" table="PRODUCTS">
<id name="productId" column="pid" >
<generator class="assigned" />
</id>
<property name="proName" column="pname" />
<property name="price"/>
</class>
</hibernate-mapping>
In this mapping file, my Product class is linked with PRODUCTS
table in the database, and next is the id element, means in the
database table what column we need to take as primary
key column, that property name we need to give hear, actually i have
been given my property name productId
which will mapped with pid column in the table.
And proName is
mapped with pname column of the PRODUCTS
table, see i have not specified any column
for the property price, this means that, our property name in the
pojo class and the column name in the table
both are same.
Remember: the first
3 lines is the DTD for the mapping file, as a programmer no need to
remember but we need to be very careful while you are copying this
DTD, program may not be executed if you write DTD wrong,
actually we have separate DTD’s for Mapping xml and Configuration
xml files.
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>
<!-- Related to the connection START -->
<property
name="connection.driver_class">oracle.jdbc.driver.OracleDriver
</property>
<property
name="connection.url">jdbc:oracle:thin:@www.java4s.com:1521:XE</property>
<property name="connection.user">user</property>
<property name="connection.password">password</property>
<!-- Related to the connection END -->
<!-- Related to hibernate properties START -->
<property name="show_sql">true </property>
<property name="dialet">org.hibernate.dialect.OracleDialect
</property>
<property name="hbm2ddl.auto">update </property>
<!-- Related to hibernate properties END -->
<!-- Related to mapping START -->
<mapping resource="product.hbm.xml" />
<!-- Related to the mapping END -->
</session-factory>
</hibernate-configuration>
In this configuration file i have been given my Oracle database
connection properties, if you are using MySql then just specify your
database related details actually its depends on you.
ClientForSave.java
import org.hibernate.*;
import org.hibernate.cfg.*;
public class ClientForSave {
public static void main(String[] args)
{
Configuration cfg = new Configuration();
cfg.configure("hibernate.cfg.xml");
SessionFactory factory = cfg.buildSessionFactory();
Session session = factory.openSession();
Product p=new Product();
p.setProductId(101);
p.setProName("iPhone");
p.setPrice(25000);
Transaction tx = session.beginTransaction();
session.save(p);
System.out.println("Object saved successfully.....!!");
tx.commit();
session.close();
factory.close();
}
}
Now compile all .java files and run ClientForSave.java and check the
output
Output Eclipse
In the database:
Note:
Note
that building blocks in each category of the palette are organized
alphabetically. To avoid scrolling, use the Filter tool in the upper
right corner of the palette to find the building blocks that you want
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