USING OC4J CONNECTION POOL

이 글은 Oracle 9i AS 9.0.x이나 Oracle AS 10g 9.0.4.x 내의 OC4J, 또는
OC4J standalone 고객들이 JDBC application을 작성하면서
database connection pool이 필요하거나 다른 connection pool에서 migration할 때 편리하게 활용하시기 위하여 작성되었습니다.

1. configuration file

 OC4J의 경우 database connection pool 설정은 config directory 내 data-sources.xml file에서 이루어집니다.
$ORACLE_HOME/j2ee/<OC4J component name>/config/data-sources.xml

 예를 들어 OAS 10g에서 OC4J component 중 'home' component에
application을 deploy하시는 경우,
$ORACLE_HOME/j2ee/home/config/data-sources.xml

2. configuration

1) data-sources.xml
예를 들어 다음과 같이 <data-source> tag를 추가해 줍니다.

<?xml version = '1.0' standalone = 'yes'?>
<!DOCTYPE data-sources PUBLIC "Orion data-sources" "http://xmlns.oracle.com/ias/dtds/data-sources.dtd">
<data-sources>
      <!--
              An example/default DataSource that uses
              Oracle JDBC-driver to create the connections.
              This tag creates all the needed kinds
              of data-sources, transactional, pooled and EJB-aware sources.
              The source generally used in application code is the "EJB"
              one - it provides transactional safety and connection
              pooling. Oracle thin driver could be used as well,
              like below.
              url="jdbc:oracle:thin:@host:port:sid"
      -->

        <data-source class="com.evermind.sql.DriverManagerDataSource"

          name="OracleDS" location="jdbc/OracleCoreDS"

          xa-location="jdbc/xa/OracleXADS" ejb-location="jdbc/OracleDS"

          connection-driver="oracle.jdbc.driver.OracleDriver"

          username="scott"

          password="tiger"

          url="jdbc:oracle:thin:@localhost:5521:oracle" inactivity-timeout="30"/>

 

<data-source class="com.evermind.sql.DriverManagerDataSource"

         name="DataSource1" location="jdbc/DataSource1"

         xa-location="jdbc/xa/DataSource1" ejb-location="jdbc/ejb/DataSource1"

         connection-driver="oracle.jdbc.driver.OracleDriver"

         username="<username>"

         password="<password>"

         url="jdbc:oracle:thin:@<IP address of db server>:<port of listener>:<SID of Oracle database instance>"

         inactivity-timeout="30"/>

</data-sources>

 

2). configuration repository update
OAS의 경우 configuration repositiory를 위해 다음과 같이 합니다.

prompt$ dcmctl shell -v
DCMCTL> updateConfig -ct oc4j -v
DCMCTL> getState -v
DCMCTL> stop -co < OC4J component name > -v
DCMCTL> start -co < OC4J component name > -v
DCMCTL> exit

3) source code
 a. JNDI lookup
예를 들어, 다음과 같이 JNDI lookup을 통하여 OC4J connection pool을 사용하도록 변경하여 주시기 바랍니다.
...
import javax.naming.*;
import oracle.jdbc.pool.OracleDataSource;

InitialContext ic = null;
OracleDataSource ods = null;
Connection conn = null;

...
try {
ic = new InitialContext();
ods = (DataSource)ic.lookup("/jdbc/DataSource1");
} catch (NamingException e) {
e.printStackTrace();
%><%= e.getMessage() %><%
}
...

 

b. getting database connection
그 다음 database connection을 가져와 사용하고 close하는 부분은 기존의 code와 같을 것입니다.
...
try {
conn = ods.getConnection();
...
} catch (SQLException e) {
...
} finally {
try {
conn.close();
} catch (SQLException e) {
...
}
}