Java Inner Class

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• Java Inner Class

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Inner Class Definition

• An inner class is associated with an instance of
  its enclosing class and has direct access to that
  object's methods and fields.
• It cannot define any static members itself.
• Objects that are instances of an inner class
  exist within an instance of the outer class.
• class OuterClass
• ...
• class InnerClass ...

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Inner Class
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Inner Class (2)

• To instantiate an inner class, you must first
  instantiate the outer class.
• Then, create the inner object within the outer
  object with this syntax
• OuterClass.InnerClass innerObject
• outerObject.new InnerClass()

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Inner Class Example

• class myClass
• static int j35
• static class myHelper
• int i10
• public static void main (String args)
• myClass.myHelper mh new
  myClass.myHelper()
• myClass mc new myClass()
• System.out.println (mh.i mc.j)

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Inner Class Example(2)

• class myClass
• int i35
• myClass ()
• myClass_A a new myClass_A()
• a.j15
• ia.j
• static class myClass_A
• int j11
• public static void main (String args)
• myClass mc new myClass()
• System.out.println (mc.i)
• myClass.myClass_A mh new myClass.myClass_A()
  
• System.out.println (mh.j)