Connection to DB using JNDI

To connect to DB using JNDI you have to perform the following steps:

  • Log onto
    Jelastic
  • Create an environment
  • Add database node into your environment
  • Modify some configuration files in a web-app
  • Create a connection in a java-class

  • Let's do it step-by-step:

    1. Create environment with database (MySQL in our case):


    2. Create a new user in a database:

    How to create new user - click here

    Database name : jelasticDb
    User_name : jelastic
    Password : jelastic

    3. Modify configuration files in your web-application:

    context.xml:

     
    <Context antiJARLocking="true" path="/JNDI">
        <Resource name="jdbc/jelasticDb" auth="Container" type="javax.sql.DataSource"
                   maxActive="100" maxIdle="30" maxWait="10000"
                   username="jelastic" password="jelastic" driverClassName="com.mysql.jdbc.Driver"
                   url="jdbc:mysql://mysql-jndi-example.{hoster_domain}/jelasticDb"/>
    </Context>

    web.xml:

     
    <resource-ref>
     <description>MySQL Datasource example</description>
     <res-ref-name>jdbc/jelasticDb</res-ref-name>
     <res-type>javax.sql.DataSource</res-type>
     <res-auth>Container</res-auth>
    </resource-ref>

    4. Create connection in java-class
     
    public class MyConnection {
    
        private DataSource dataSource;
    
        public MyConnection() {
            try {
    
                InitialContext context = new InitialContext();
                dataSource = (DataSource) context.lookup("java:comp/env/jdbc/jelasticDb");
    
            } catch (NamingException ex) {
                Logger.getLogger(MyConnection.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    
        public Connection getConnection() {
            Connection conn = null;
            try {
                conn = dataSource.getConnection();
            } catch (SQLException ex) {
                Logger.getLogger(MyConnection.class.getName()).log(Level.SEVERE, null, ex);
            }
            return conn;
        }
    }