import java.io.*;
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.sql.*;
public class ConnectionFactory
{

/**

oracle?? 分頁

select * from (
select a.*, ROWNUM rn from ( select * from user_info )? a
where ROWNUM<=40 )
where rn >=21

?

*/
??? private static Properties config = new Properties();
???
??? static
??? {
??????? try
??????? {
??????????? InputStream in = ConnectionFactory.class.getClassLoader().getResourceAsStream("dbconfig.properties");
??????????? config.load(in);
??????????? in.close();
??????? }catch(IOException e)
??????? {
??????????? e.printStackTrace();
??????????? throw new ExceptionInInitializerError(e.getMessage());
??????? }
??? }
???
??? public static Connection getConnection()
??? {
??????? if(config.getProperty("jndi-name") != null)
??????? {
??????????? return getJndiConnection();
??????? }
???????
??????? return getDirectConnection();
??? }
???
??? public static Connection getJndiConnection()
??? {
??????? Connection con = null;
??????? try
??????? {
/**context.xml

數據源的配置
<Context>
????? <Resource name="jdbc/oracle" auth="Container" type="javax.sql.DataSource" maxActive="2" maxIdle="1" maxWait="-1"
????? username="openlab" password="open123" driverClassName="oracle.jdbc.driver.OracleDriver" url="jdbc:oracle:thin:@192.168.0.20:1521:tarena"/>
</Context?
*/
??????????? Context ctx = new InitialContext();
??????????? DataSource ds = (DataSource)ctx.lookup("java:comp/env/" + config.getProperty("jndi-name"));
??????????? con = ds.getConnection();
??????? }catch(Exception e)
??????? {
??????????? e.printStackTrace();
??????? }
??????? return con;
??? }
???
??? public static Connection getDirectConnection()
??? {
??????? Connection con = null;
??????? try
??????? {
??????????? Class.forName(config.getProperty("driver"));
??????????? con = DriverManager.getConnection(config.getProperty("dburl") ,config.getProperty("user"), config.getProperty("password"));
??????? }catch(ClassNotFoundException cne)
??????? {
??????????? cne.printStackTrace();
??????? }catch(SQLException sqle)
??????? {
??????????? sqle.printStackTrace();
??????? }
???????
??????? return con;
??? }
???
??? public static void close(ResultSet rs, Statement st, Connection con)
??? {
??????? try
??????? {
??????????? rs.close();
??????? }catch(Exception e)
??????? {
??????? }
???????
??????? try
??????? {
??????????? st.close();
??????? }catch(Exception e)
??????? {
??????? }
???????
??????? try
??????? {
??????????? con.close();
??????? }catch(Exception e)
??????? {
??????? }
??? }
???
??? public static void main(String[] args) throws Exception
??? {
??????? Connection con = ConnectionFactory.getConnection();
??????? System.out.println(con);
??????? con.close();
??? }
}