Objects/Classes

Objects/Classes

1. Object-Oriented Programming

   • Modelling applications on real-world objects
     • Objects don't need every real-world quality of its namesake

2. Objects

   • Real-World: Car, attirbutes: Color, # of valves, plate #, # of tires
   • Java: Has attributes and can perform actions
     • Field: Attribute
     • Method: Action
       • Returns
         • Object
         • Void
           • Nothing
       • Main
         • Entry Point to application
     • Field and Method: One or other necessary, not both
     • Created using "new" function
     • Null
       • Variable contains no value
   • Also called Instance

3. Class

   • Blueprint for object
     • Constructor
       • Creates Objects
         • No Return Value
       • Added by Compiler
   • Create abstraction for a problem
   • 3 Things to consider when making
     • Class Name
     • Fields
     • Methods