APIs for our Object Examples

An API is a list of the public constructor and method headers, so we can drop “public”

API for Point:

Point(int x, int y)   create point at (x,y)

int getX()            return x-coordinate

int getY()            return y-coordinate

double distanceFromOrigin()   return distance of point from origin

void setLocation(int x, int y)      set new location for point

void translate(int dx, int dy)      move point by (dx, dy) to a new location

String toString()                   return a String describing a point

Quick example of use:

Point p1 = new Point(2,4);

p1.translate(1,1);

API for PhoneEntry (should have descriptions)

PhoneEntry(String name0, String phoneNo0)
String getName()
String getPhoneNo()
String areaCode()
void changeAreaCode(String newCode)
boolean isValid()
String toString()

Quick example of use:

PhoneEntry pe1 = new PhoneEntry(“Len”, “617-222-3333”);

System.out.println(“area code = “ + pe1.areaCode());

API for Automobile

       Automobile(String make, String model, int year, String vehicleID)  
String getMake()      car’s make
String getModel()     car’s model
   int getYear()      car’s model year
String getVIN()       car’s vehicle ID

Quick example of use:

Automobile car = new Automobile(“Toyota”, “Camry”, 2011, “1GH1234567”);

System.out.println(“car’s year is “+ car.getYear());