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/*
* This dumb applet queries your database and returns all rows from
* a table called dumb_query.
*/

// Import the JDBC classes
import java.sql.*;

// Import the java classes used in applets
import java.awt.*;
import java.io.*;
import java.util.*;

public class JdbcApplet extends java.applet.Applet
{
// The driver to load
static final String driver_class = "oracle.jdbc.driver.OracleDriver";

// The connect string
static final String connect_string =

"jdbc:oracle:thin:apenner/csc4240@carbon.cudenver.edu:1521:oracle";

// This is the kind of string you woudl use if going through the
// Oracle 8 connection manager which lets you run the database on a
// different host than the Web Server. See the on-line documentation
// for more information.


// The query we will execute
static final String query = "select * from flight_arrivals";


// The button to push for executing the query
Button execute_button;

// The place where to dump the query result
TextArea output;

// The connection to the database
Connection conn;

// Create the User Interface
public void init ()
{
this.setLayout (new BorderLayout ());
Panel p = new Panel ();
p.setLayout (new FlowLayout (FlowLayout.LEFT));
execute_button = new Button ("Click Here");
p.add (execute_button);
this.add ("North", p);
output = new TextArea (10, 60);
this.add ("Center", output);
}

// Do the work
public boolean action (Event ev, Object arg)
{
if (ev.target == execute_button)
{
try
{
// Clear the output area
output.setText (null);

// See if we need to open the connection to the database
if (conn == null)
{
// Load the JDBC driver
output.appendText ("Loading JDBC driver " + driver_class + "\n");
Class.forName (driver_class);

// Connect to the database
output.appendText ("Connecting to " + connect_string + "\n");
conn = DriverManager.getConnection (connect_string);
output.appendText ("Connected\n");
}

// Create a statement
Statement stmt = conn.createStatement ();

// Execute the query
output.appendText ("Executing query " + query + "\n");
ResultSet rset = stmt.executeQuery (query);

// Dump the result
while (rset.next ())
output.appendText (rset.getString (1) + "\n");

// We're done
output.appendText ("done.\n");
}
catch (Exception e)
{
// Oops
output.appendText (e.getMessage () + "\n");
}
return true;
}
else
return false;
}
}