gistfile1.java

package Helpers;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public final class Database {

    public static Database instance = new Database();

    private static final String driver = "org.apache.derby.jdbc.EmbeddedDriver";
    private static final String url = "jdbc:derby://localhost:1527/dn_irc";
    private static final String username = "dn_irc";
    private static final String password = "dn_irc";

    private Database() {
        try {
            Class.forName(driver);
        } catch (ClassNotFoundException ex) {
            System.err.println(ex.getMessage());

        }
    }

    /**
     * Open a connection with this database
     */
    private Connection getConnection() throws SQLException, IOException {
        return DriverManager.getConnection(url, username, password);
    }

    public static boolean isRegistered(String username, String password) {
        Connection con = null;
        try {
            con = instance.getConnection();
            Statement s = con.createStatement();
            s.executeQuery("SELECT COUNT(*) FROM users WHERE username LIKE '" + username + "' AND password LIKE '" + password + "'");
            s.getResultSet().next();
            return s.getResultSet().getInt(1) == 1;
        } catch (IOException | SQLException ex) {
            System.err.println(ex.getMessage());
            return false;
        } finally {
            try {
                con.close();
            } catch (SQLException ex) {
                System.err.println(ex.getMessage());
            }
        }
    }

    public static void logMessage(String username, String message) {
        Connection con = null;
        try {
            con = instance.getConnection();
            Statement s = con.createStatement();
            s.executeUpdate("INSERT INTO LOG (Username, Message) VALUES ('" + username + "','" + message + "')");
        } catch (IOException | SQLException ex) {
            System.err.println(ex.getMessage());
        } finally {
            try {
                con.close();
            } catch (SQLException ex) {
                System.err.println(ex.getMessage());
            }
        }
    }
    
    public static void main(String[] args) {
        String username = "Vuokko";
        String password = "letmein";
        String message = "Lorem ipsum dolor sit amet!";
        
        System.out.println(Database.isRegistered(username, password));
        
        Database.logMessage(username, message);
        
        System.out.println("Done!");
    }
}