TableViewer viewer = new TableViewer(parent, SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL | SWT.VIRTUAL | SWT.FULL_SELECTION);

       List<String> labels = ....


       for (int i = 0; i < labels.length; i++) {
	    TableViewerColumn column = new TableViewerColumn(viewer, SWT.NONE);
	    column.getColumn().setText(labels[i]);
	    column.getColumn().setResizable(true);
	    column.getColumn().setMoveable(true);
	}


	Table table = viewer.getTable();
	table.setHeaderVisible(true);
	table.setLinesVisible(true);

        Table table = viewer.getTable();
	
	
	for( int i = 0; i < table.getColumnCount(); i++ )
	    table.getColumn(i).pack();

public void inputChanged(final Viewer viewer, Object oldInput, final Object newInput) {
	PlatformUI.getWorkbench().getDisplay().asyncExec( new Runnable(){

	    @Override
	    public void run() {
		
		if( viewer.getControl().isDisposed() )
		    return;
		
               // insert elements into the view	
		
		// now refresh the view (this should be not necessary)
		viewer.refresh();
		
               // get the table of this viewer
      	       Table table = viewer.getTable();
	
	       // iterate on each column and pack it
 	       for( int i = 0; i < table.getColumnCount(); i++ )
	         table.getColumn(i).pack();
	    }
	   
	    
	});

public synchronized void run() {
       List<T> loadedElements = // load elements

	this.contentProvider.inputChanged( this.viewer, loadedElements, loadedElements );
	
	try {
	    this.sleep(2000);
	    PlatformUI.getWorkbench().getDisplay().asyncExec( new Runnable(){

		    @Override
		    public void run() {
                          // here pack the columns as above
		    }
	    });
	    
	} catch (InterruptedException e) {
	    // TODO Auto-generated catch block
	    e.printStackTrace();
	}
	
	
    }