EBoard 02 (Section 1): Getting started with Java

Warning This class is being recorded.

Getting started (this will be our normal start-of-class sequence)

• Grab a card. The card will have a computer name and a location.
• Remember the name and location.
• Drop the card back in the jar.
• Navigate to the computer.
• If you arrive first, start the lab.
• When both partners arrive, introduce yourselves.

For the future: I’m happy to reserve a (somewhat random) seat at the front of the classroom for those who need a front seat as an adjustment or accommodation. Just let me know.

Approximate overview

• Administrative stuff [10–15 min]
• Questions on readings.
• Lab

Administrivia

Introductory notes

• I’m still Sam (or SamR).
• Our mentors are still Micah and Pom.
• I tend to respond faster to Direct Messages (Chat) on Teams than email.
• I will do my best to post a link to the Otter.ai transcript on Teams, in the recordings channel.
• Even though Sam is providing notes, you should also take your own; there is evidence that doing so helps you learn and remember.
• Our class site is still under development. Let me know if you find things missing, including images.
  • I know that one of the two Wednesday readings is missing. Expect it on Tuesday. (Sorry.)
• I’ll attempt quick attendance.

Upcoming Token activities

Academic

• Convocation, Thursday, 11:00 a.m. President Harris.

Cultural

Peer

Wellness

Upcoming work

• Introductory survey and syllabus questions due tonight at 10:30 p.m.
• Readings for Wednesday. (Do before class; nothing to turn in. Ask questions on Teams.)
• Lab from today due before class on Wednesday.

Administrative questions (e.g., about the syllabus)

Do we really have SoLAs?

No.

Are you going to post readings from the book?

Um … yeah, that’s in the plan. We’ll be using CLRS starting around week six.

We’ll mostly be using my readings. CLRS provides more formality.

There are old editions of CLRS in the CS learning center and a legal free edition online through the library.

Questions on the readings

Lab

• Sam will try to figure out problems with the style sheet. [Done.]
• For the FizzBuzz problem, in main, create a PrintWriter named pen and use fizzbuzz(pen, 100).
• Goal is to finish the ArrayProblems.java by next class.
  • Together is great.
  • On your own is fine.

Debrief

• Sam prefers that you use PrintWriter objects rather than System.out because it makes it easier to change the behavior of your program.
  • Print the first 100 lines of FizzBuzz to stdout: fizzbuzz(new PrintWriter(System.out, true), 100)
  • Print the first 1000 lines of FizzBuzz to the file “killbuzz.txt”: fizzbuzz(new PrintWriter(new File("killbuzz.txt"), 1000))
• FizzBuzz is a traditional problem that early programmers seems to struggle with. (It is, unfortunately, also a drinking game.)

Two approaches to FizzBuzz

A standard approach: Four cases (multiple of 15, multiple of 5, multiple of 3, anything else)

    if (i % 15 == 0) {
      pen.println("fizzbuzz");
    }
    else if (i % 5 == 0) {
      pen.println("buzz");
    }
    else if (i % 3 == 0) {
      pen.println("fizz");
    }
    else {
      pen.println(i);
    }

An alternate approach: Always print fizz when it’s a multiple of 3, always print buzz when it’s a multiple of 5, add appropriate extra stuff.

    boolean printed = false;
    if (i % 3 == 0) {
      pen.print("fizz");
      printed = true;
    }
    if (i % 5 == 0) {
      pen.print("buzz");
      printed = true;
    }
    if (!printed) {
      pen.print(i);
    }
    pen.println();