Java Nested Class

Normal Class (Non-nested Class) can only is public, abstract or final. For nested classes, the static is allowed.

Nested classes (private, public, protected), 2 Categories.

1. Static Nested Class (Very Different from C # Static Class)

Alpha:have access to all the static members of its parent class.

Beta:can instantiate objects by New Parentclass.staticnestclass (). Now allowed to create objects in C #.

Gamma:can has non-static members.

Delta:same as Gamma. Cannot access parentclass.this.

2. Non-static Nested Class (Inner Class)

Alpha:have access to all the members of their parent class.

Beta:can instantiate objects by New ParentClass (). New Innerclass ().

Gamma:cannot has the static members, the except for final static fields.

Delta:variable Shadowing:

ParentClass.this.memberName, Parent class member.

This.membername, ParentClass.InnerClass.this.memberName-Inner class member

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1. Interface can only is defined inside a top-level class, an Interface or in static context because interfaces is inhere ntly Static.

2. Anonymous Classes:

Interface/abstractclass obj = new Interface/abstractclass (Empty for Interface. Initialize for abstract class) {

String/int ...;

public void Implementabstractmethoda () {...}

public void Implementabstractmethodb () {...}

}; <--semicolon in the end

Java Nested Class