Types of Inheritance in Java

1. Single Inheritance

• A class extends only one parent class

• Syntax:

  class A {
  	// ...
  }
  class B extends A {
  	// ...
  }
  

2. Multiple Inheritance

• Java does NOT support multiple inheritance for classes

• Multiple interface implementation is allowed

• Syntax:

  class A {
  	// ...
  }
  class B {
  	// ...
  }
  class C extends A, B // not allowed in Java
  {
  	// ...
  }
  

  interface A {
  	// ...
  }
  interface B {
  	// ...
  }
  class C implements A, B // allowed in Java
  {
  	// ...
  }
  

3. Hierarchical Inheritance

• One parent class can have multiple child classes

• Example:

  class A {
  	// ...
  }
  class B extends A {
  	// ...
  }
  class C extends A {
  	// ...
  }
  

4. Multi-level Inheritance

• A derived class becomes a parent for another class

• Example:

  class A {
  // ...
  }
  class B extends A {
  // ...
  }
  class C extends B {
  // ...
  }
  

5. Hybrid Inheritance

• A combination of different inheritance types

Casting in Inheritance

Up-casting