Lecture slides and materials
Lecture notes
Variables and expressions
- % is a rest operator (not modulo)
- Unary operators (++, –, !)
- Assignment operator is a return expression
Java naming conventions
- Camel case → Variable names
- Pascal case → Class names
Casting operations
int a = (int)(3.14 * 5)- When casting to an integer it rounds down by default
- Bad idea to compare doubles using the operator ==
- If when printing a number (int) without specifying its type, Java will assume it’s type to be an Integer (the memory for an int is 32bit)
- Overflow / Underflow → when adding two integers, the sum overflows the memory of an integer and overflows
Constants
- Naming conventions: ALL_CAPITALS
Garbage collection
- When a variable’s scope ends, it is still present in RAM, even if not accessible
- Garbage collector will remove value from memory when not needed anymore
Methods
- Methods group related statements that re-occur together in a task
- Visibility
- Return Type
- method Name
- Parameters
Scanner library