Primitives

  • primitives are lowercase
  • nonprimitives are uppercase
  • Collegeboard need-to-know primitives: Boolean, Int, Double

Casting

  • changing a variable from one data type to another
  • widening: happens automatically, going from smaller to larger data type
  • narrowing: need to declare to address overflow error, going from larger to smaller data type

Operators

  • (+) is addition
  • (-) is subtraction
  • (/) is division
  • (*) is multiplication
  • (%) finds the remainder
  • example: x += 7 increases the varaible by 7

HW

2006 FRQ

2a 

public double purchasePrice() {
    return getListPrice() * (1+taxRate);
}

3a 

public int compareCustomer(Customer other)
  {
    int compare =  getName().compareTo(other.getName());
    if (compare == 0) {
      return getID() - other.getID();
    }
    else {
      return compare;
    }
  }