Dependency Inversion Principle

The Dependency Inversion Principle states that:

1. High-level modules should not depend on low-level modules. Both should depend on abstractions.

2. Abstractions should not depend upon details. Details should depend upon abstractions.

The best way to explain this principle is by giving an example. Let's assume we have a worker class that is a low level class and a Manager class that is a high level class. The Manager class contains many complex functionalities which it implements along with the Worker class, so the classes will look something like this:

class Worker { 
 
   public void work() { 
       // ....working 
   } 
} 
 
class Manager { 
   
   //--Other Functionality 
   
   Worker worker; 
 
   public void setWorker(Worker w) { 
       worker = w; 
   } 
 
   public void manage() { 
       worker.work(); 
   } 
} 

Here the Manager...