Held: Tuesday, 10 September 2013

Back to Outline 06 - Debugging. On to Outline 08 - Some Basic Types: Numbers and Strings in Java.

Summary

We consider the design of arrays as an ADT and then the specifics of arrays in Java.

Related Pages

• Reading: Arrays
• Lab: Arrays
• Javadoc
• EBoard (Source) (PDF)

Overview

• About HW 2
• ADT Design
• Arrays
• Strings (maybe)

Administrivia

• A final reminder to register for the 2nd-year retreat. It looks like a good opportunity to do lots of things - talk more about group work, learn from alums, think about choosing a major, etc.
• It sounds like there was some demand that I focus on the syntax and semantics of imperative Java, so I've rearranged the syllabus (including today) to go over it.
  • Rearranging stuff put me even further behind! Readings may not be ready in time, and class sessions will probably focus on lecture + discussion + recitation.
• Reminder: Mentor session Wednesday night at 8pm
• Readings for Wednesday (expect them later today):
  • Strings in Java
  • Numbers in Java
• Homework 3 is ready!
• EC opportunities:
  • Humanities Center Speaker Sarah Hendron, Wednesday, 7:30 p.m., JRC101 Waking the Machines: Art, Design, and Adaptive Technology
  • Learning from Alumni 2:15-4:05 Thursday: Ian Lunderskov '08
  • Tentative Thursday Extra: Matt Atherton '95
  • CS Table, Friday: Trusting Trust.
  • More?

Some Initial Notes on HW2

• Many of you spent about the amount of time I would have hoped 4-5 hours.
• The biggest challenge seems to have been the lab equipment (Git and Eclipse). Also learning a bit about syntax.
• A number of you said that getting the syntax right for parts C and D was hard. There's a reason that I wrote "It's okay if this code doesn't compile."
• The average one came from a bug in Java's implementation of binary search, a bug that was first noticed by someone at Google.
  
  • I included the problem to remind you that you really do need to think about boundary cases.

ADTs, Revisted

When you design an ADT, you should think about

• Philosophy
• Practica
• Procedures
• ...

One big conceptual issue: Are you a minimalist or a maximalist? (Do you put as little or as much as possible in your design?)

After designing, think about implementation.

Arrays in Java

• Arrays are both an ADT (in the sense that we can think about them as meeting some abstract goals that can be implemented in many ways) and a data structure (in the sense that we can also pay attention to their implementation.
• We started to look at Arrays as ADTs on the first day of class.
• We'll continue today.

Strings in Java (optional)