@Override
  public Connection getConnection() throws SQLException {
    return DriverManager.getConnection(url, username, password);
  }
Create a connection factory with given parameters.

@param hostname host running postgres
@param dbname name of the postgres db
@param username username for postgres db
@param password password for postgres db
ambari-server/src/main/java/org/apache/ambari/server/controller/jdbc/JobHistoryPostgresConnectionFactory.java