SWT uses two classes, Tree and TreeItem, to implement tree controls.
Creating Trees
public Tree(Composite parent, int style)
Trees can allow either a single selection or multiple selections.
Tree Styles
StyleDescription
SWT.SINGLEAllows only one item in the tree to be selected at a time. This is the default.
SWT.MULTIAllows multiple items in the tree to be selected at the same time.
SWT.CHECKDisplays a checkbox to the left of each of the root items in the tree.