The class diagram for connection pool

Explaination

• SimpleConnectionPool: This class is suitable only for single-threaded applications. i.e., If we create a connection pool using this class, then we can’t share this across different threads. So use this class to manage the connection pool only when you have a single-threaded application.
• ThreadedConnectionPool: As the name suggests, this class used in a multithreaded environment. i.e., the connection pool created using this class can be shared between multiple threads.
• PersistentConnectionPool: This class is used in the multithread application, where a pool assigns persistent connections to different threads. As the name suggests, each thread gets a single connection from the pool, i.e., the thread can’t use more than one connection from the pool.