Java Object

Java Object

1. Java Class

   • Class Name
   • Fields
     • lowercase
     • Field type
   • Methods
     • Return Type
       • double
         • 12.34, 45.678
       • int
         • 1, 2, 3, 4
       • Object
       • null
         • No reference to Object
           • ObjectName fieldName;
       • boolean
         • True or False
       • String
         • char
           • "a", "b", "c"
         • "Hello World."
       • void
     • Method Name
     • List of Arguments
     • returnType methodName (listOfArguments)
     • main
       • public static void main (String[] args)
       • run classes using "java"
         • java className arg1 arg2 arg3 ...
   • Constructors
     • No return value
     • Assign Values
     • Create & Assign
       • new ObjectName(20, 300.00);

2. Create Object/ Instantiate

   • new ObjectName();
   • ObjectName fieldName = new ObjectName();
   • Parameters
     • Referencing
       • objectReference.methodName
     • Assigning Values
       • objectReference.arg1 = 42;