What is Boxing and Unboxing? and explain in detail?

Boxing:

• Boxing is the process of converting a variable type to reference type.
• Supports 2 types
• Implicit boxing
• Explicit boxing
• Boxing 20 times Costlier than normal initialization

Unboxing:

• Unboxing is the process of converting a reference type to value type.
• Supports only 1 type
• Explicit Unboxing
• Unboxing 4 times costlier than normal initialization

Example: Program for boxing and Unboxing:

Output:

• Boxing is 20 times costlier than normal initialization, because whenever a boxing is done following tasks will be performed internally.
• Runtime will search for the respective data with in the stack.
• A copy of this value is made into heap.
• Reference to this copy is maintained from the object variable.
• Unboxing is 4 times costlier than normal initialization, because whenever a boxing is done following tasks will be performed internally.
• Object referenced value is searched within the Heap.
• A copy of this is made into stack.