This document summarizes Hibernate, an object-relational mapping tool for Java. It discusses how Hibernate provides APIs for storing and retrieving Java objects from a database, maps Java classes to database tables, and minimizes database access through caching and fetching strategies. The document also includes examples of Hibernate configuration files and mappings that define relationships between entities.

1. Hibernate presentation
The more you know, the more you realize how much you don't know.
The less you know, the more you think you know.
~David T. Freeman
author: Khoa.NK

2. - The Java Persistence API provides a POJO persistence
model for object-relational mapping.
Java Persistence API

3. 1. Takes care of mapping Java classes to database tables
(none-code).
2. Provides simple APIs for storing and retrieving Java
objects.
3. SQL types be familiar Java Objects
4. Minimize database access with smart fetching
strategies.
5. Save 90% cost (databases)
Hibernate Advantages:

4. Hibernate Architecture

5. <hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password"></property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.default_schema">hibernate</property>
<property name="show_sql">true</property>
<property name="hibernate.hbm2ddl.auto">update</property>
<property name="packagesToScan">com.nkk.hibernate.present.entities</property>
<mapping resource="entities/Book.hbm.xml"></mapping>
<mapping resource="entities/Category.hbm.xml"></mapping>
</session-factory>
</hibernate-configuration>
Hibernate Configuration

6. <hibernate-mapping>
<class name="com.nkk.hibernate.present.entities.CategoryEntity" table="category">
<id name="id" type="int">
<column name="id" precision="10" scale="0" />
<generator class="increment" />
</id>
<property name="name" type="string">
<column name="name" length="200" not-null="true" />
</property>
</class>
</hibernate-mapping>
Hibernate Mapping

7. <set name="books" inverse="true">
<key>
<column name="category_id" not-null="true" length="10"></column>
</key>
<one-to-many class="com.nkk.hibernate.present.entities.BookEntity"></one-to-many>
</set>
<many-to-one name="category" class="com.nkk.hibernate.present.entities.CategoryEntity" fetch="select">
<column name="category_id" not-null="true"></column>
</many-to-one>
Hibernate O2M & M2O

8. - Cache level 1
- Cache level 2
- Query cache
Hibernate Caching

9. Hibernate lazy loading

10. - Hibernate Query language
- Hibernate Criteria query
- isDirty()
- Hibernate Spring session
- Hibernate optimization
Orthers