Problema com geração de relatório Ireport

package operations;

import com.mysql.jdbc.Connection;
import connection.DatabaseSettings;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.logging.Level;
import java.util.logging.Logger;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.view.JasperViewer;

/**
 *
 * @author Junior
 */
public class RelatorioVenda {

    private Connection connection;

    public RelatorioVenda() throws SQLException {
        try {
            Class.forName("org.postgresql.Driver");
            connection = (Connection) DriverManager.getConnection(DatabaseSettings.DATABASE_URL, DatabaseSettings.DATABASE_LOGIN, DatabaseSettings.DATABASE_PASSWORD);
        } catch (ClassNotFoundException ex) {
            Logger.getLogger(RelatorioVenda.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void GerarRelatorio() {
        try {
            
            HashMap parametros = new HashMap();
            JasperPrint jp = JasperFillManager.fillReport("./jasper/venda.jasper", parametros, connection);
            JasperViewer jrv = new JasperViewer(jp);
            jrv.setVisible(true);
            
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public static void main (String [] args){
        try {
            new RelatorioVenda().GerarRelatorio();
        } catch (SQLException ex) {
            Logger.getLogger(RelatorioVenda.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}