This document presents the object pool design pattern. The object pool pattern creates and manages a group of objects (the pool) that can be reused to avoid the cost of creating new objects. When an object is needed, it is pulled from the pool rather than creating a new instance. The object is returned to the pool when it is no longer needed so it can be reused again later. The object pool pattern satisfies the single responsibility principle by having the pool class solely manage the object lifecycle and handling concurrency issues. It is useful when there are a limited number of expensive to create objects that will be needed repeatedly.

1. OBJECT POOL
DESIGN
PATTERN PRESENTED TO
Prof. Dr. Shazia Arshad
PRESENTED BY
Muhammad Naeem 2019-CS-232
Talha Ashraf 2019-CS-239

2. Definition
Object pool pattern is a software creational
design pattern that is used in situations where the
cost of initializing a class instance is very high.
Basically, an Object pool is a container that
contains some amount of objects. So, when an
object is taken from the pool, it is not available in
the pool until it is put back.

3. The Object Pool Design Pattern satisfies the
Single Responsibility Principle (SRP) of SOLID.
The SRP states that a class should have only one reason
to change. In the context of the Object Pool pattern,
the pool class is responsible for managing a collection
of objects and providing them to clients when
requested. The pool class has the responsibility of
creating and destroying objects, managing the state of
the pool, and handling concurrency issues.
Principle to whom it satisfies?

4. When we have work to allocate or deallocate many
objects
Also, when we know that we have a limited number
of objects that will be in memory at the same time.
When to use?

5. Layman
Example

6. UML Diagram

7. Client: This is the class that uses an object of the
PooledObject type.
ReuseablePool: The PooledObject class is the type that
is expensive or slow to instantiate, or that has limited
availability, so is to be held in the object pool.
ObjectPool: The Pool class is the most important class
in the object pool design pattern. ObjectPool maintains
a list of available objects and a collection of objects
that have already been requested from the pool.

8. Code
Example

9. It offers a significant performance boost.
It manages the connections and provides a way
to reuse and share them.
Object pool pattern is used when the rate of
initializing an instance of the class is high.
Advantages

10. Thanks :)