IPC in Android

AIDL (Android Interface Definition Language), Messenger, and Broadcast IPC (Inter-Process Communication) are mechanisms in Android that allow communication between different components or processes. Here’s a brief overview of each:

AIDL (Android Interface Definition Language):

• Type: AIDL is a mechanism for inter-process communication based on interfaces.
• Usage: It is primarily used for communication between different Android applications or between different components within the same application running in different processes.
• How it works: AIDL is used to define interfaces that can be implemented by different components. The interface is then used to facilitate communication between these components by passing data between them.
• Example: AIDL is commonly used in scenarios where a service in one process needs to communicate with an activity or service in another process.

Messenger

• Type: Messenger is a higher-level Android API built on top of AIDL.
• Usage: It is used for one-way communication between processes.
• How it works: Messenger uses a message queue to pass messages between processes. It involves creating a Messenger object in one process, passing it to another process, and then using it to send messages between the two processes.
• Example: Messenger is often used when you need to send messages or commands from one part of your application to another part running in a separate process.

Broadcast IPC (Inter-Process Communication)

• Type: Broadcast IPC involves sending and receiving broadcast messages.
• Usage: It is used for loosely-coupled communication between different components or applications.
• How it works: In Broadcast IPC, one component broadcasts an intent, and any other components interested in that intent can receive it. It’s a publish-subscribe model where components register to receive specific broadcasts using intent filters.
• Example: Broadcast IPC is commonly used for system-wide events or notifications. For instance, an application can broadcast an intent when a specific event occurs, and other components can register to receive that intent and respond accordingly.

In summary, AIDL is a low-level mechanism for defining interfaces and communication, Messenger is a higher-level abstraction built on AIDL for one-way communication, and Broadcast IPC is a mechanism for loosely-coupled communication through broadcasted intents. The choice of which to use depends on the specific requirements and use case of your application.