Object-oriented ------------- anonymous internal class

1. Definitions of anonymous internal classes: in a class, another class is called an internal class. Anonymous internal class: If a class is used only once in the entire operation, it can be defined as an anonymous internal class. Anonymous internal classes are developed based on abstract classes and interfaces.

Interface A {public void printInfo (); // defines the interface} class B implements A {// implements the public void printInfo () {System. out. println ("Hello World !!! ") ;}}; Class X {public void fun1 () {this. fun2 (new B ();} public void fun2 (A a) {. printInfo () ;}}; public class NoInnerClassDemo01 {public static void main (String args []) {new X (). fun1 (); // instantiate the object of Class X and call the fun1 () method }};

 

If Class B is only used once, it is unnecessary to define a class for it. In this case, you can use an anonymous internal class.

Interface A {public void printInfo (); //} class X {public void fun1 () {this. fun2 (new A () {public void printInfo () {System. out. println ("Hello World !!! ") ;}}) ;}Public void fun2 (A a) {. printInfo () ;}}; public class NoInnerClassDemo02 {public static void main (String args []) {new X (). fun1 (); // instantiate the object of Class X and call the fun1 () method }};

 

2. Conclusion 1. Various development frameworks are often used in Java Development, and a large number of anonymous internal classes are referenced in the frameworks. 2. Anonymous internal classes are developed based on abstract classes and interfaces.