🍃🤷‍♂️ When do you know you have to use 'prototype' scope rather than 'singleton'?

The decision to use 'prototype' scope instead of 'singleton' in Spring depends on the nature of the bean and how you want Spring to manage its lifecycle. Here are some scenarios where you might consider using the 'prototype' scope:

💪 Stateful Beans:

If the bean maintains mutable state that should not be shared among multiple clients, 'prototype' scope may be more appropriate.Example: A shopping cart where each user should have their own independent cart instance.

🧵 Thread Safety:

If the bean is not thread-safe and should have a separate instance for each thread, 'prototype' scope is suitable.

Example: A bean that involves heavy computation or uses non-thread-safe components.

🔄️ Dynamic Configuration:

If the bean's configuration changes dynamically and you want each client to get a fresh instance with the latest configuration.Example: A configuration bean that reads properties from an external source.

🗑️ Short-lived Instances:

If the bean's lifecycle is short-lived, and creating a new instance for each request is more efficient than reusing a shared instance.

Example: A temporary object used for a specific operation.

😨 Avoiding Side Effects:

If the bean performs actions that have side effects, and you want to avoid those side effects affecting other parts of the application.

Example: A bean that interacts with external systems and its behavior should not impact other components.

☝️ Remember that the 'prototype' scope means that a new instance of the bean is created every time it is requested. This can lead to increased resource usage, so it's essential to balance the benefits of a fresh instance with the potential overhead.

In summary, use 'prototype' scope when you want each client to have its own independent instance of the bean, and the shared state is not desired. If a shared state is acceptable or beneficial, then 'singleton' scope may be more appropriate.

#java #spring #scope #singleton #prototype