Second level Caching in hibernate and Hibernate Example 9

Second level Caching- Across multiple sessions. Even if session is closed, the object would be saved in second level cache and if called again, will be directly accessed from there only.

Types of second level cache provider in hibernate:

1)EhCacheProvider

2) OSCacheProvider

Configuration changes in hibernate.cfg.xml

    

    1.    <property name="cache.provider_class">org.hibernate.cache.EhCacheProvider</property>  

    2.    <property name="hibernate.cache.use_second_level_cache">true</property>  

Person.java

@Entity(name="PERSON")

@Cacheable

@Cache(usage=CacheConcurrencyStrategy.READ_ONLY)

public class Person implements java.io.Serializable{

     private static final long serialVersionUID = 1L;

     private String name;

    

     @Id

     @GeneratedValue(strategy=GenerationType.AUTO)

     private long id;

     public String getName() {

           return name;

     }

     public void setName(String name) {

           this.name = name;

     }

     public long getId() {

           return id;

     }

     public void setId(long id) {

           this.id = id;

     }

}

               

hibernate.cfg.cml

<hibernate-configuration>

      <session-factory>

           

            <property name="cache.use_second_level_cache">true</property>

            <property name="cache.provider_class">org.hibernate.cache.EhCacheProvider</property>

           

            <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>

            <property name="connection.url">jdbc:oracle:thin:@172.16.7.236:20300:prtp</property>

            <property name="connection.username">MOBI_CLEANUP_TEST1</property>

            <property name="connection.password">MOBI_CLEANUP_TEST1</property>

            <!-- JDBC connection pool (use the built-in) -->

            <property name="connection.pool_size">1</property>

            <property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>

            <!-- Enable Hibernate's automatic session context management, by default

                  its update -->

            <property name="hbm2ddl.auto">update</property>

            <!-- Echo all executed SQL to stdout -->

            <property name="show_sql">true</property>

            <!-- <mapping class="org.javadsalgo.dto.UserDetailsDTO"/> <mapping class="org.javadsalgo.dto.Vehicle"/>

                  <mapping class="org.javadsalgo.dto.TwoWheeler"/> <mapping class="org.javadsalgo.dto.FourWheeler"/> -->

            <mapping class="org.javadsalgo.dto.Person" />

            <!-- <mapping resource="org/javadsalgo/model/UserDetailsDTO.hbm.xml" /> -->

      </session-factory>

</hibernate-configuration>

Output:

Hibernate: select person0_.id as id0_0_, person0_.name as name0_0_ from PERSON person0_ where person0_.id=?