Android Handler vs Thread vs HandlerThread

1. A Handler is a tool in Android used to handle messages and communication between threads, mainly for sending messages to a message queue and processing them at a specified time. Handlers are typically used in conjunction with Loopers and Messages, and can be created in the main thread or in a separate thread.
2. In Java, the Thread class is used to handle multithreading, and in Android, you can also use Thread to create new threads. By inheriting the Thread class or implementing the Runnable interface, multitasking operations can be implemented in Android applications.
3. HandlerThread is a special thread class in Android that extends from the Thread class and includes a Looper and Handler internally, making it easier to handle messages in a child thread. It is commonly used for executing time-consuming operations or recurring tasks in the background thread.

Summary:

1. The Handler is a tool used to manage message processing and communication between threads.
2. The Thread class in Java is utilized for managing multiple threads, and it can also be used in Android to create new threads.
3. HandlerThread is a specialized thread class in Android that includes Looper and Handler internally, used for processing messages in the background thread.