how to use DefaultCellEditor to make column of the JTable to get only numbers and round them with two signs after dot?

Question

I am not sure if this is the right way to do this but I think so. I have tried to use DecimalFormat but I cant understand it. Can someone help me? Is this the correct way to do this DefaultCellEditor + DecimalFormat?

@AndrewThompson, you edited and let "write way" stay there!? — HericDenis, Nov 07 '12 at 11:12
@HericDenis 1) I did not edit (or carefully read) the body, just the tags. 2) When I do, it is mostly the 'red squiggly underlines' that FF thinks are wrongly spelled, that draws my eye to them. So even if I had edited the body, it is unlikely I would have noticed the difference between 'write' and 'right'. ;) — Andrew Thompson, Nov 07 '12 at 11:15
Have a look at [How to Use Tables](http://docs.oracle.com/javase/tutorial/uiswing/components/table.html) in particular [Using an Editor to Validate User-Entered Text](http://docs.oracle.com/javase/tutorial/uiswing/components/table.html#validtext) — MadProgrammer, Nov 07 '12 at 11:15

score 4 · Answer 1 · edited May 23 '17 at 12:04

override column class by using Double.Class
for XxxTableCellEditor to use JFormattedTextField or JSpinner as Editor, formatted by proper methods from NumberFormat or DecimalNumberFormat, including rounding
set DefaultTableCellRenderer for desired colum
you can to set (too) proper Rounding method from NumberFormat

for example

TableColumnModel tcmAmount = myTable.getColumnModel();    
TableColumn tcAmount = tcmAmount.getColumn(2);
tcAmount.setCellRenderer(new DRManMmAmount(1)); // decimal precision

and

   private static class DRManMmAmount extends DefaultTableCellRenderer {

        private static final long serialVersionUID = 1L;
        int precision = 0;
        Number numberValue;
        NumberFormat nf;

        public DRManMmAmount(int p_precision) {
            super();
            setHorizontalAlignment(javax.swing.SwingConstants.RIGHT);
            precision = p_precision;
            nf = NumberFormat.getNumberInstance();
            nf.setMinimumFractionDigits(p_precision);
            nf.setMaximumFractionDigits(p_precision);
            //nf.setMinimumFractionDigits(2);
            //nf.setMaximumFractionDigits(2);
        }

        @Override
        public void setValue(Object value) {
            if ((value != null) && (value instanceof Number)) {
                numberValue = (Number) value;
                value = nf.format(numberValue.doubleValue()); 
            }
            super.setValue(value);
        }
    }

how to use DefaultCellEditor to make column of the JTable to get only numbers and round them with two signs after dot?

1 Answers1