//only variables from the last registered group are important now
List groupsList = getDjd().getGroupsList();
JRDesignGroup registeredGroup = (JRDesignGroup)groupsList.get(groupsList.size()-1);
if (col instanceof ExpressionColumn && ((ExpressionColumn)col).getExpressionForCalculation() != null){
ExpressionColumn expcol = (ExpressionColumn)col;
expression.setText(expcol.getTextForExpressionForCalculartion());
expression.setValueClassName(expcol.getExpressionForCalculation().getClassName());
} else {
expression.setText(col.getTextForExpression());
expression.setValueClassName(col.getValueClassNameForExpression());
}