CSS 2267 - Review Sheet for Test 3

1. Exceptions and Handling Them - study slides at http://clem.mscd.edu/~evansell/LECTURES/Exceptions.ppt. Study the code examples there.
   • What an exception is
   • Meaning of the keywords "throws" and "throw" - distinguish these - slide 8
   • Exceptions are Objects.  The class Exception extends Throwable  (Error also extends Throwable - what is Error?)
   • Java Class Hierarchy of Exceptions - see slide 4 of slides on Exceptions - know what are checked exceptions and what are not
   • Java requires your code to handle all checked exceptions
   • "handle" exception means either put it in a try-catch-finally block or announce that your method throws the exception - be able to write examples of each
   • Know try-catch-finally structure (t-c-f) - know what's optional and what's required (slides 5, 6, 7) - finally is options, even catch is.  But try-clause must have either catch or finally.
   • Know the control flow of t-c-f:  finally is always executed - no matter what.  Be able to figure out flow given code.
   • Know the control flow of how exceptions propagated up through method calls - slides 9, 10, 12.
2. Adapters  see note at http://clem.mscd.edu/~evansell/LECTURES/Adapters.html - be able to distinguish between an adapter class and a listener interface - know some simple examples (MouseAdapter, MouseMotionAdapter, WindowAdapter, etc.)
3. Input/Output Streams - study slides at http://clem.mscd.edu/~evansell/LECTURES/Adapters.html - study  the code examples there.
   • What is an IO stream?  what is a source? a sink? What is an input stream? what is an output stream?
   • What is the difference between a basic (simple, primitive) IO stream versus a filtered (or higher level) IO stream?  Basic ones only do IO one unit at a time (a data unit is either one byte or one character).  Higher level streams can do IO for larger groupings (of basic units) at a time. 
   • Understand why IO commands can generate IOExceptions?  Know that you need to put these in try-catch blocks.  Know how to write these.
   • What do we mean by a byte-oriented IO Stream? what does this do for input? for output?
   • What are the primary (simple) byte oriented streams? (InputStream, OutputStream).  What are their key methods? (InputStream: int read( ), void close( ); OutputStream void write( int), void close( )).
   • What are the main higher level byte oriented IO streams?  What is a BufferedInputStream?  BufferedOutputStream? DataInputStream? etc. Examples? See slides 4-7.
   • What do we mean by the term character (text) oriented stream?  what does this do for input? for output?  what conversions occur?
   • What are the primary (simple) character oriented input/output streams (Reader, Writer)?  What are the basic methods of Reader and Writer? (Reader: int read( ), void close( ),  Writer: void write(int), void close( )).  
   • What is an InputStreamReader? an OutputStream Writer?   Know how to go from a byte oriented stream to a character oriented stream.
   • What is a FileReader?  FileWriter?  BufferedReader? PrintWriter?  Examples? (see slides 12,13,14).  What is the readLine( ) command for BufferReader? what does it do?  Similarly explain println( ) for PrintWriter.
4. GUI - General Ideas - http://clem.mscd.edu/~evansell/LECTURES/UNIT6.ppt - overall
   • Understand basic ideas of GUI construction - components, containers, adding components into containers, layout and layout managers
   • The concept of the GUI containment hierarchy diagram - can you draw the rough sketch of a GUI given a containment hierarchy? Given a sketch of the GUI, can you draw the containment hierarchy?  Given GUI-building code that adds components to a container according to some layout manager, could you sketch the GUI?
5. GUI - AWT - http://clem.mscd.edu/~evansell/LECTURES/UNIT6.ppt - slides 2-8
   • Know the basic AWT inheritance hierarchy (slide 2)
   • Know about how to build menus - what do you need?  MenuBar, Menu, MenuItem.   In what order and in what steps do you build a menu bar and add it to a frame?
   • How to implement listeners to get action events from Buttons, TextFields, MenuItems - review code examples like slides 7-8
   • Know the basic AWT layout managers and the visual-effect differences between them: FlowLayout, GridLayout, BorderLayout (slide 6) and CardLayout(less emphasis on CardLayout).  Gotchas: For BorderLayout you have to give a second argument to the add( ) command - to tell whether to put the component in the North, South, Center, etc.   You don't need this for other layout managers.  If you don't give a second argument to add( ), then BorderLayout will put the component  in the center.  Also: Border and Grid layouts do not respect component sizes - they force everything to fit their scheme.  Flow layout respects sizes.
6. GUI - Swing - http://clem.mscd.edu/~evansell/LECTURES/UNIT6.ppt - slides 9-end
   • Know what Swing provides that AWT didn't - be able to name at least 4 added Swing features/capabilities.
   • What is a JComponent?  How does it differ from a plain old AWT Component.  Know how to use paintComponent(Graphics G) (don't forget - always first call super.paintComponent(G)).
   • Know what the top level containers in Swing are (JWindow, JFrame, JDialog).   Understand that you can't add components directly to top level containers, nor can you directly set the layout of a top-level container.  You have to get the content pane of the top level container and add to it or set its layout.   For instance, if top is a JFrame and you want to add a button b, you DON 'T say top.add(b) - rather you say            top.getContentPane().add(b).   Or you can make a JPanel jp of your own, and add the button to it (jp.add(b)) and then maker it the content pane by top.setContentPane(jp).
   • For a JFrame, understand the components: content pane, menu bar, and glass pane.  What do these each mean? Understand this visually.
   • Know about the special Swing layout manager BoxLayout.  How it renders added components - as one horizonal row or one vertical stack.  Box layout respects component sizes.    APPLIES ONLY TO SWING JComponents!!!!
   • Be able to read code that uses Swing menus (JMenuBar, JMenu, JMeniItem).