CS141: Topics for Sept 4 & 6, 2013
Homework and Reading
The reading and homework for this week can be found here: Lab 2: Fundamental Data Types
Chapter 2 is full of a lot of vocabulary. It is important that you understand what these words mean otherwise you will be
lost as we go forward. For practice, check out the WileyPlus Chapter 2 Flash Cards!
The words in green will be dealt with in much more detail later, so don't worry if they don't completely make sense.
primitive type vs object
class & object
instance vs static method
parameter & argument
Topics: Variable types, math, I/O
- Variables: What are they, how do you create, name, and initialize them?
- Types: What is a type? Why do we have them? What are examples? Can we convert from one to another?
- Java Statements: What is a statement, expression, value?
- What is a "literal"?
- Assignment statement: What is its syntax?
- Doing Arithmetic
- Operators - binary (+, -, /, *, %) , unary (-, ++, --)
- Operator Precedence and when you must use parentheses
- The Math class for functions such as sqrt, pow, etc. -
Learn to use the javadoc api !
- Conversion between numeric types.
- Magic numbers: What are they? Why are they a problem?
- Constants: What are they? Why do we have them?
- Comments: What are they? Why do we have them? What is their syntax?
- Common Pitfalls:
- Forgetting to declare and/or initialize a variable.
- Declaring a variable multiple times.
- Using integer division when you don't mean to.
- Problem Solving techniques
- Don't jump into coding too quickly. Understand problem, try example by hand, write pseudocode.
- Stepwise refinement - break problem into a sequence of steps that lead to the full solution. Implement
one step at a time, compiling (compile time errors) and testing your code (run time erros)
- Strings: What is a string? What are the String operators? Look at String API.
- Primitive types (int, float, etc) vs Object types (String, Scanner, etc):
- Primitive operators and syntax
- Object/Class operators and syntax: Methods, dot notation, parameter/argument. Static vs instance.
In Class Practice Activities