Hibernate hbm.xml

Hibernate hbm.xml

This tutorial is helpful to understand about hbm.xml

In hibernate, there is two way of mapping - first one is by using hibernate annotation and second one is by using hbm.xml.

When you use hbm.xml, just modify default hibernate SessionFactory class in hibernate-cfg.xml by passing your "hbm.xml" file path as an argument to resource method.

Example: Here we are taking an example of employee table.

Employee.hbm.xml file is your hbm.xml file in which table column and their types are mapped.

Employee.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="net.roseindia.table.Employee" table="employee">
<id name="empId" type="int" column="emp_id">
<generator class="native" />
</id>
<property name="EmpName" type="string" column="emp_name" />
<property name="salary" type="int" column="emp_salary" />
<property name="designation" type="string" column="designation" />
<property name="address" type="string" column="address" />
</class>
</hibernate-mapping>

hibernate-cfg.xml is configuration file of hibernate where you map hbm.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>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">none</property>
<mapping resource="Employee.hbm.xml"/>
</session-factory>

</hibernate-configuration>