=========================  QUICK DEMO: Random objects

> import java.util.Random;
> Random x = new Random();
> x.nextInt( 10 )
3
> x.nextInt( 2 )
0
> x.nextInt( 2 )
1
> x.nextInt( 2 )
0
> x.nextInt( 200 )
81
> x.nextInt( 200 )
105
> x.nextInt( 200 )
149
> x.nextInt( 200 )
111
> x.nextInt( 200 )
110
> for (int i = 0; i < 10; i++)
    System.out.println( x.nextInt( 10 ) );
9
0
2
9
8
5
7
1
5
3


=========================  OPENING EXERCISE: class to simulate a Die

> Die d = new Die();
> d.roll()                  // several times!

                                   -----   discuss parts of the class
                                   -----   no instance variables!?



=========================  NEXT EXERCISE: supporting different-sided dice

> Die d = new Die( 6 );
> d.roll()                           // several times!

> Die duodecimal = new Die( 12 );
> duodecimal.roll()                  // several times!

> Die twenty = new Die( 20 );
> twenty.roll()                      // several times!

                                   -----   discuss new parts of the class
                                   +++++   always a "default" constructor
> Die hex = new Die( 16 );
> hex.roll()                         // several times!
> Die standardDie = new Die();
> standardDie.roll()                 // several times!

                                   -----   no accessors??


=========================  SLIDES: main() method

// Using Tools/Run Document's Main Method     <F2>

> java Die                // *****   ALSO BY HAND IN Interactions PANE
10

                          // *****   ALSO BY HAND AT COMMAND LINE
mac os x > cd .../cs1-media/intro-prog-java/bookClasses/
mac os x > java Die
11

=========================  IDEA: using javadoc to generate web doc for classes

// look at the Javadoc for Random
// via http://java.sun.com/j2se/1.4.2/docs/api/overview-summary.html

// ... and generate javadoc for our code

mac os x > cd  /Users/wallingf/home/teaching/cs1/sessions/session20
mac os x > mkdir javadoc-example/
mac os x > cp DiffSound.java Sound.java javadoc-example/
mac os x > cd javadoc-example/
mac os x > javadoc *.java
                                   -----   Sound.java:9: cannot find symbol
                                   -----   symbol: class SimpleSound
                                   -----   
                                   -----   DiffSound.java:9: warning - @date is an unknown tag.
mac os x > open index.html



=========================  SLIDES: files

                                   -----   AFTER HOW TO WRITE A FILE SLIDE
> import java.io.*;
> BufferedWriter file = new BufferedWriter( new FileWriter("output.txt") );
> file.write( "foo" );
> file.newLine();
> file.write( "bar" );
> file.newLine();
> file.close();
                                   -----   Open output.txt in Finder.
                                   -----        (in dir with Dr. Java)
                                   -----   Use complete path to specify.


=========================  TASK: add a write() method to DiffSound

                                   -----   write first sample
                                   -----   write # of diffs
                                   -----   write each diff

                                   -----   Complications:
                                   -----   ... I/O exception
                                   -----   ... files of characters

> Sound s = new Sound( FileChooser.getMediaPath("ew/the-voice-raw.aiff") );
> DiffSound d = s.compress();
> d.write( "ew/the-voice-raw.diff" );

                                   -----   Open the file.  See the data.
                                   -----   But the file is **bigger**

                                   -----   Finish with slides.