fTreeViewer.setUseHashlookup(true);
	protected void createTreeViewer(Composite parent, int width, int height) {		Tree tree= new Tree(parent, SWT.CHECK | SWT.BORDER);		GridData data= new GridData(GridData.FILL_BOTH);		data.widthHint= width;		data.heightHint= height;		tree.setLayoutData(data);		fTreeViewer= new CheckboxTreeViewer(tree);		fTreeViewer.setContentProvider(fTreeContentProvider);		fTreeViewer.setLabelProvider(fTreeLabelProvider);		fTreeViewer.addTreeListener(this);		fTreeViewer.addCheckStateListener(this);		fTreeViewer.addSelectionChangedListener(this);	}