Mind Map (Classes and Objects)

Mind Map (Classes and Objects)

1. Instantiate/Create object

   • Constructors
   • new keyword / assign ref variable
     • Object / Instance
       • Fields (Attributes)
         • Primitive
           • Stack
         • Reference/Object variable(s)
           • if no value
             • "null" value
               • Test if null, use ==
       • Methods (actions)
       • Heap
       • If object variable is assigned
         • Address Object
   • main

2. Define class

   • Class name
     • Organize, for functionality etc.
       • input / output
         • java.io
       • java core
         • java.lang
       • package keyword
         • Packages
           • complining non-deault package
             • change directory to working directory (use javac)
           • complining class belonging to package
             • change directory to working directory (use java)
       • class name = package name
         • fully qualified name
       • no package declaration
         • belong to default package
   • UML Class Diagram