- Design robust classes
- Don't rely on the programmer to use the class correctly
- Constructor
  - Special method that is executed when a new class is created via the new method
  - Must have the same name as its class
  - Syntax
    public <class name> ( <parameters> ) {
        <statements>
    }
  - No return type
  - Modifier
    - Need not be public
    - Anything else 
      - Extremely rare
      - Not covered
- Default constructor
  - If no constructor defined, automatically provided by compiler
  - If do define own, no default is added
- Can define multiple constructors for the same class
  - Lets programmer create a new instance of the class in different ways
  - Conditions for multiple constructors:
    1. Different number of parameters OR
    2. Different combination of types among parameters
    - Different parameter names still invalid
- Constructor purpose: initialize object to valid state
  - Do so by intializing all member data in the constructor
- Define multiple constructors more cleanly
  - Have them call each other
  - Substitute reserved word this for the class name in the constructor being called
    - Recommend have the calling line be the only line in the constructor
    - At the very least, should be the first line of the constructor

Quick Check
1.  ClassA is invalid because it has a return type
    ClassC is invalid because, not only does it have a return type, it is also lacking a visibility modifier
2.  The constructor with parameter int X conflicts with the constructor with parameter int Y because they have the same number and type of parameters.
3.  class Student {

        private String name;

        public Student() {
            this("");
        }

        public Student(String initName) {
            name = initName;
        }

        public void assign(String newName) {

            name = newName;

        }

        public String identify() {

            return name;

        }

    }