TableSorter performance

Question

Hi All,
Please help it is urgent. I am using table sorter provided in Swing tutorial when i sort the table by any column and start feeding the table with updated after that as I need the table to be updated automatically, CPU usages exceeds 80% and may reach 100%. if i canceled sorting CPU usage drops down to 10%. Could you help me?

Answer 1

Below is some code used to sort columns within a JTable. It is implemented in an application that routinely receives 10k to 30k rows, and is fairly quick about the job it does.
    // The following code was found posted freely at http://javaalmanac.com/egs/javax.swing.table/Sorter.html
    public void sortAllRowsBy(DefaultTableModel model, int colIndex, boolean ascending)
        Vector data = model.getDataVector();
        Collections.sort(data, new ColumnSorter(colIndex, ascending));
        model.fireTableStructureChanged();
    public class ColumnSorter implements Comparator
        int colIndex;
        boolean ascending;
        ColumnSorter(int colIndex, boolean ascending)
            this.colIndex = colIndex;
            this.ascending = ascending;
        public int compare(Object a, Object b)
            Vector v1 = (Vector) a;
            Vector v2 = (Vector) b;
            Object o1 = v1.get(colIndex);
            Object o2 = v2.get(colIndex);
            // Treat empty strings like nulls
            if (o1 instanceof String && ((String) o1).length() == 0)
                o1 = null;
            if (o2 instanceof String && ((String) o2).length() == 0)
                o2 = null;
            boolean number = true; // Assume they are numbers
            Double d1 = null;
            Double d2 = null;
            try
            { // Are these strings represent Numbers. (first remove any commas or dollar signs that may be present)
                d1 = Double.valueOf(o1.toString().replaceAll("[,\\$]", ""));
                d2 = Double.valueOf(o2.toString().replaceAll("[,\\$]", ""));
            catch (Exception notANumber)
                number = false; // assumption wrong, they are not numbers
            finally
                if (number)
                    o1 = d1;
                    o2 = d2;
            // Sort nulls so they appear last, regardless
            // of sort order
            if (o1 == null && o2 == null)
                return 0;
            else if (o1 == null)
                return 1;
            else if (o2 == null)
                return -1;
            else if (o1 instanceof Comparable)
                if (ascending)
                    return ((Comparable) o1).compareTo(o2);
                else
                    return ((Comparable) o2).compareTo(o1);
            else
                if (ascending)
                    return o1.toString().compareTo(o2.toString());
                else
                    return o2.toString().compareTo(o1.toString());
    }