if (txtDniColaborador.getText().isEmpty()) {
        JOptionPane.showMessageDialog(null, "DEBE INGRESAR UN DNI");
    } else {

        tabla = txtTabla.getText();
        dni = txtDniColaborador.getText();
   try {
        Class.forName("com.mysql.jdbc.Driver");

        Connection conexion = DriverManager.getConnection("jdbc:mysql://localhost:3306/dbDaca?zeroDateTimeBehavior=convertToNull", "root", "1234");
        Statement st = conexion.createStatement();
        ResultSet rst = st.executeQuery("SELECT CONCAT("+tabla+") LIKE '%" + tabla + "%' FROM  WHERE CONCAT(DniColaborador) LIKE '%" + dni + "%'");
        ResultSetMetaData rsmt = rst.getMetaData();
        int nrocolumnas = rsmt.getColumnCount();
        DefaultTableModel modelo = new DefaultTableModel();
        this.jTable1.setModel(modelo);
        for (int x = 1; x <= nrocolumnas; x++) {
            modelo.addColumn(rsmt.getColumnLabel(x));

        }

        while (rst.next()) {
            Object[] fila = new Object[nrocolumnas];

            for (int y = 0; y < nrocolumnas; y++) {
                fila[y] = rst.getObject(y + 1);

            }

            modelo.addRow(fila);

        }

    } catch (ClassNotFoundException ce) {
        ce.printStackTrace();
    } catch (SQLException se) {

        se.printStackTrace();
    }
    }