java.lang.ClassNotFoundException: org.postgresql.Driver

Создал класс DatabaseHelper

@SuppressWarnings("serial")
public class DatabaseHelper implements Serializable {
private JDBCConnectionPool connectionPool = null;
private static ResourceBundle bundle = ResourceBundle.getBundle("rts.data.databaseHelper");
public DatabaseHelper() {
    initConnectionPool();
}
private void initConnectionPool() {
    try {
        connectionPool = new SimpleJDBCConnectionPool("org.postgresql.Driver",bundle.getString("connectionUri") ,bundle.getString("userName"), bundle.getString("password"), 2, 2);
        } catch (SQLException e) {
            e.printStackTrace();
        }
}   
public JDBCConnectionPool getConnectionPool() {
    return connectionPool;
}
}

Теперь запускаю WildFly и в ответ получаю ошибки:

 [org.jboss.modules] (default task-7) Failed to define class rts.data.databaseHelper in Module "deployment.OR.war:main" from Service Module Loader: java.lang.NoClassDefFoundError: Failed to link rts/data/databaseHelper (Module "deployment.OR.war:main" from Service Module Loader): rts/data/databaseHelper (wrong name: rts/data/DatabaseHelper)

и

[com.vaadin.server.DefaultErrorHandler] (default task-7) : java.lang.RuntimeException: Specified JDBC Driver: org.postgresql.Driver - initialization failed.

и

Caused by: java.lang.ClassNotFoundException: org.postgresql.Driver from [Module "deployment.OR.war:main" from Service Module Loader]

В чем может быть проблема?