Java Code:
import java.text.Collator;
import java.util.Locale;

import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;

public class Snippet2 {

  public static void main(String[] args) {
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    final Table table = new Table(shell, SWT.BORDER);
    table.setHeaderVisible(true);
    TableColumn column1 = new TableColumn(table, SWT.NONE);
    column1.setText("Column 1");
    TableColumn column2 = new TableColumn(table, SWT.NONE);
    column2.setText("Column 2");
    TableItem item = new TableItem(table, SWT.NONE);
    item.setText(new String[] { "a", "3" });
    item = new TableItem(table, SWT.NONE);
    item.setText(new String[] { "b", "2" });
    item = new TableItem(table, SWT.NONE);
    item.setText(new String[] { "c", "1" });
    column1.pack();
    column2.pack();
    column1.addListener(SWT.Selection, new Listener() {
      public void handleEvent(Event e) {
        // sort column 1
        TableItem[] items = table.getItems();
        Collator collator = Collator.getInstance(Locale.getDefault());
        for (int i = 1; i < items.length; i++) {
          String value1 = items[i].getText(0);
          for (int j = 0; j < i; j++) {
            String value2 = items[j].getText(0);
            if (collator.compare(value1, value2) < 0) {
              String[] values = { items[i].getText(0),
                  items[i].getText(1) };
              items[i].dispose();
              TableItem item = new TableItem(table, SWT.NONE, j);
              item.setText(values);
              items = table.getItems();
              break;
            }
          }
        }
      }
    });
    column2.addListener(SWT.Selection, new Listener() {
      public void handleEvent(Event e) {
        // sort column 2
        TableItem[] items = table.getItems();
        Collator collator = Collator.getInstance(Locale.getDefault());
        for (int i = 1; i < items.length; i++) {
          String value1 = items[i].getText(1);
          for (int j = 0; j < i; j++) {
            String value2 = items[j].getText(1);
            if (collator.compare(value1, value2) < 0) {
              String[] values = { items[i].getText(0),
                  items[i].getText(1) };
              items[i].dispose();
              TableItem item = new TableItem(table, SWT.NONE, j);
              item.setText(values);
              items = table.getItems();
              break;
            }
          }
        }
      }
    });
    shell.open();
    while (!shell.isDisposed()) {
      if (!display.readAndDispatch())
        display.sleep();
    }
    display.dispose();
  }

}