Interface Versus Abstract Class

- Interface are stateless(no instance fields.).
- Interface provide behavior, not state.
- Abstract classes provide behavior and state.

Lamda Expressions Versus Anonymous Classes

• Lamdas are more succinct.  
• Lamdas do not create additional class files.  
• Not every occurrence of lamda crates a new object.  
• On the other hand:     

         - Lamdas only work for FIs

         - Anonymous classes can have state(That is, fields)