Q157. Name four Container classes.
Window, Frame, Dialog, FileDialog, Panel, Applet, or ScrollPane

Q158. What is the difference between a Choice and a List?
A Choice is displayed in a compact form that requires you to pull it down to see the list of available choices. Only one item may be selected from a Choice. A List may be displayed in such a way that several List items are visible. A List supports the selection of  one or more List items.

Q159. What class of exceptions are generated by the Java run-time system?
The Java runtime system generates RuntimeException and Error exceptions.

Q160. What class allows you to read objects directly from a stream?
The ObjectInputStream class supports the reading of objects from input streams.