how to sort JTable by providing column index externally.

Question

I would like to implement sorting on JTable by providing column index externally in program. Here is my sample code in which i have initialize JTable, Add one Column and 30 rows to JTable. After rows has been added i am sorting JTable by providing column index 0 but i could not get sorted data. how can i get my first column in sorted order? what's wrong with my code. Why sortCTableonColumnIndex() method could not sort data for specify column index?

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.RowSorter;
import javax.swing.SortOrder;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableColumn;
import javax.swing.table.TableRowSorter;

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
/**
 *
 * @author Admin
 */
public class Test {

    private JTable oCTable;
    private DefaultTableModel oDefaultTableModel;
    private JScrollPane oPane;
    private JTableHeader oTableHeader;
    private TableRowSorter sorter;

    public void adddata() {
        for (int i = 0; i < 30; i++) {
            Object[] row = new Object[1];
            String sValueA = "A";
            String sValueB = "A";
            row[0] = "";
            if (i % 2 == 0) {
                if (i < 15) {
                    sValueA = sValueA + sValueA;
                    row[1] = sValueA;
                } else {
                    if (i == 16) {
                        sValueB = "D";
                        row[1] = sValueA;
                    } else {
                        sValueB = sValueB + sValueB;
                        row[1] = sValueA;
                    }

                }
            } else {
                if (i < 15) {
                    sValueB = sValueB + sValueB;
                    row[1] = sValueB;
                } else {
                    if (i == 17) {
                        sValueB = "C";
                        row[1] = sValueB;
                    } else {
                        sValueB = sValueB + sValueB;
                        row[1] = sValueB;
                    }

                }
            }

        }
    }

    public void createTable() {
        oCTable = new JTable();
        oDefaultTableModel = new DefaultTableModel();
        oCTable.setModel(oDefaultTableModel);
        oTableHeader = oCTable.getTableHeader();
        oCTable.setAutoResizeMode(oCTable.AUTO_RESIZE_OFF);
        oCTable.setFillsViewportHeight(true);
        JTable oTable = new LineNumberTable(oCTable);
        oPane = new JScrollPane(oCTable);
        oPane.setRowHeaderView(oTable);
        JPanel oJPanel = new JPanel();
        oJPanel.setLayout(new BorderLayout());
        oJPanel.add(oPane, BorderLayout.CENTER);
        JDialog oDialog = new JDialog();
        oDialog.add(oJPanel);
        oDialog.setPreferredSize(new Dimension(500, 300));
        oDialog.pack();
        oDialog.setVisible(true);

    }

    public void insert() {
        oDefaultTableModel.addColumn("Name");
        int iColumnPlace = ((DefaultTableModel) oCTable.getModel()).findColumn("Name");
        CellRendererForRowHeader oCellRendererForRowHeader = new CellRendererForRowHeader();
        TableColumn Column = oCTable.getColumn(oTableHeader.getColumnModel().getColumn(iColumnPlace).getHeaderValue());
        Column.setPreferredWidth(300);
        Column.setMaxWidth(300);
        Column.setMinWidth(250);
        Column.setCellRenderer(oCellRendererForRowHeader);



        for (int i = 0; i < 30; i++) {
            Object[] row = new Object[1];
            String sValueA = "A";
            if (i % 2 == 0) {
                if (i < 15) {
                    sValueA = sValueA + "a";
                    oDefaultTableModel.insertRow(oCTable.getRowCount(), new Object[]{""});
                    oDefaultTableModel.setValueAt(sValueA, i, 0);
                } else {
                    if (i == 16) {
                        sValueA = sValueA + "b";
                        oDefaultTableModel.insertRow(oCTable.getRowCount(), new Object[]{""});
                        oDefaultTableModel.setValueAt(sValueA, i, 0);
                    } else {
                        sValueA = sValueA + "c";
                        oDefaultTableModel.insertRow(oCTable.getRowCount(), new Object[]{""});
                        oDefaultTableModel.setValueAt(sValueA, i, 0);
                    }

                }
            } else {
                if (i < 15) {
                    sValueA = sValueA + "d";
                    oDefaultTableModel.insertRow(oCTable.getRowCount(), new Object[]{""});
                    oDefaultTableModel.setValueAt(sValueA, i, 0);
                } else {
                    if (i == 17) {
                        sValueA = sValueA + "e";
                        oDefaultTableModel.insertRow(oCTable.getRowCount(), new Object[]{""});
                        oDefaultTableModel.setValueAt(sValueA, i, 0);
                    } else {
                        sValueA = sValueA + "f";
                        oDefaultTableModel.insertRow(oCTable.getRowCount(), new Object[]{""});
                        oDefaultTableModel.setValueAt(sValueA, i, 0);
                    }

                }
            }

        }
    }

    public void showTable() {
        createTable();
        insert();
        sortCTableonColumnIndex(0, true);

    }

    public void sortCTableonColumnIndex(int iColumnIndex, boolean bIsAsc) {
        sorter = new TableRowSorter(oDefaultTableModel);
        List<RowSorter.SortKey> sortKeys = new ArrayList<RowSorter.SortKey>();
        if (bIsAsc) {
            sortKeys.add(new RowSorter.SortKey(iColumnIndex, SortOrder.ASCENDING));
        } else {
            sortKeys.add(new RowSorter.SortKey(iColumnIndex, SortOrder.DESCENDING));
        }
        sorter.setSortKeys(sortKeys);
        oDefaultTableModel.fireTableStructureChanged();
        oCTable.updateUI();


    }

    public static void main(String[] argu) {
        Test oTest = new Test();
        oTest.showTable();


    }

    class CellRendererForRowHeader extends DefaultTableCellRenderer {

        public Component getTableCellRendererComponent(JTable table, Object value,
                boolean isSelected, boolean hasFocus, int row, int column) {
            JLabel label = null;
            try {
                label = (JLabel) super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
                if (column == 0) {
                    label.setBackground(new JLabel().getBackground());
                    label.setForeground(Color.BLACK);
                }
            } catch (RuntimeException ex) {
            }
            return label;

        }
    }

    class LineNumberTable extends JTable {

        private JTable mainTable;

        public LineNumberTable(JTable table) {
            super();
            mainTable = table;
            setAutoCreateColumnsFromModel(false);
            setModel(mainTable.getModel());
            setAutoscrolls(false);
            addColumn(new TableColumn());
            getColumnModel().getColumn(0).setCellRenderer(mainTable.getTableHeader().getDefaultRenderer());

            getColumnModel().getColumn(0).setPreferredWidth(40);
            setPreferredScrollableViewportSize(getPreferredSize());

        }

        @Override
        public boolean isCellEditable(int row, int column) {
            return false;
        }

        @Override
        public Object getValueAt(int row, int column) {
            return Integer.valueOf(row + 1);
        }

        @Override
        public int getRowHeight(int row) {
            return mainTable.getRowHeight();
        }
    }
}

Answer 1

slight change in method tends facilitate sorting.

public void sortCTableonColumnIndex(int iColumnIndex, boolean bIsAsc) {
        oCTable.setAutoCreateRowSorter(true);
        DefaultRowSorter sorter = ((DefaultRowSorter) oCTable.getRowSorter());
        List<RowSorter.SortKey> sortKeys = new ArrayList<RowSorter.SortKey>();
        if (bIsAsc) {
            sortKeys.add(new RowSorter.SortKey(iColumnIndex, SortOrder.ASCENDING));
        } else {
            sortKeys.add(new RowSorter.SortKey(iColumnIndex, SortOrder.DESCENDING));
        }
        sorter.setSortKeys(sortKeys);
    }

Thanks

Answer 2

You should really stick to the Java coding standards when writing Java code, but whatever route you go, you should at the very least be consistent.

Looking at your code you don't actually set the sorter on the table. From the JavaDocs the following is missing from your code:

TableModel myModel = createMyTableModel();
JTable table = new JTable(myModel);
table.setRowSorter(new TableRowSorter(myModel));

So it would look something like this in your code (or at least with your non-standard conventions removed)

public void createTable() {
    tableModel = new DefaultTableModel();
    table = new JTable(tableModel);
    sorter = new TableRowSorter<DefaultTableModel>(tableModel);
    table.setRowSorter(sorter);
    ...
}