Java_ class and Object 08_ form parameter and return value problem

1. Formal Parameters:

Class Name: An object that requires this class

Abstract class Name: A subclass object that requires this class

Interface Name: An implementation class object that requires this interface

Case one:

　　

Case TWO:

　　

Case THREE:

　　

2. Return value type:

Class Name: Returns the object of the class

Abstract class Name: Returns the subclass object of the class

Interface Name: An object that returns an implementation class for the interface

Case one:

　　

Case TWO:

　　

Case THREE:

　　

3. Chain-Type programming

Object. Method 1 (). Method 2 () .... Method N ();

This usage: In fact, after the invocation of Method 1 (), an object should be used;

After Method 2 () is called, an object should be returned.

After the method n () call is complete, the object may or might not be an object.

Case one:

　　

Java_ class and Object 08_ form parameter and return value problem