Example: Datalink

/////////////////////////////////////////
// PutGetDatalinks is an example application 
// that shows how to use the JDBC
// API to handle datalink database columns.
/////////////////////////////////////////
import java.sql.*;
import java.net.URL;
import java.net.MalformedURLException;

public class PutGetDatalinks {
    public static void main(String[] args) 
    throws SQLException 
    {
        // Register the native JDBC driver.
        try {
            Class.forName("com.ibm.db2.jdbc.app.DB2Driver");
        } catch (Exception e) {
            System.exit(1);  // Setup error.
        }

        // Establish a Connection and Statement with which to work.
        Connection c = DriverManager.getConnection("jdbc:db2:*local");    
        Statement s = c.createStatement();

        // Clean up any previous run of this application.
        try {
            s.executeUpdate("DROP TABLE CUJOSQL.DLTABLE");
        } catch (SQLException e) {
            // Ignore it - assume the table did not exist.
        }

        // Create a table with a datalink column.  
        s.executeUpdate("CREATE TABLE CUJOSQL.DLTABLE (COL1 DATALINK)");

        // Create a PreparedStatement object that allows you to add
        // a new datalink into the database. Since conversing
        // to a datalink cannot be accomplished directly in the database, you
        // can code the SQL statement to perform the explicit conversion.
        PreparedStatement ps = c.prepareStatement("INSERT INTO CUJOSQL.DLTABLE 
                                                   VALUES(DLVALUE( CAST(? AS VARCHAR(100))))");

        // Set the datalink. This URL points you to an article about
        // the new features of JDBC 3.0.
        ps.setString (1, "http://www-106.ibm.com/developerworks/java/library/j-jdbcnew/index.html");

        // Process the statement, inserting the CLOB into the database.
        ps.executeUpdate();

        // Process a query and obtain the CLOB that was just inserted out of the 
        // database as a Clob object.
        ResultSet rs = s.executeQuery("SELECT * FROM CUJOSQL.DLTABLE");
        rs.next();
        String datalink = rs.getString(1);


        // Put that datalink value into the database through
        // the PreparedStatement. Note: This function requires JDBC 3.0
        // support.
        /*
        try {
            URL url = new URL(datalink);
            ps.setURL(1, url);
            ps.execute();
        } catch (MalformedURLException mue) {
            // Handle this issue here.
        }

        rs = s.executeQuery("SELECT * FROM CUJOSQL.DLTABLE");
        rs.next();
        URL url = rs.getURL(1);
        System.out.println("URL value is " + url);
        */

        c.close(); // Connection close also closes stmt and rs.
    }
}