What is the advantages of reflection over normal programming in JAVA? [duplicate]

My question is why do we use Reflection in JAVA?

Suppose I have to create an object of class. Then I may use the simple code as follows:

PersonClass pc = new PersonClass();

Where PersonClass is the class whose object I want to create. It's so simple.

Then why we will use the following code snippet using Reflection:

Class cls = Class.forName("PersonClass"); 
PersonClass obj = (PersonClass) cls.newInstance();

What is the advantage of it?

And also tell me the other advantages of Reflection in JAVA.