Java loading class method and instance method through reflection mechanism

Suppose the class name of a class is a. Now I want to find one of the methods Functionb () and call this method through the reflection mechanism.

Method functionb = A.class.getmethod ("functionb", Class<?>...paramtype);

Functionb.invoke (A.class,object...args);

The parameters of the surface here are: Paramtype is an array of parameter types for method functionb. Args is the specific parameter after the call.

A.class can be understood as the receiver. Or it is understood as the class in which the method is located, and if it is a static method, the argument can write null.