How can real-time message push be achieved in Java?

In Java, real-time message push can be achieved using WebSocket or Server-Sent Events (SSE).

1. WebSocket implementation:
2. In Java, one can implement WebSocket using open-source libraries like Java-WebSocket or Spring WebSocket.
3. Firstly, we need to create a WebSocket server that can listen for client connection requests.
4. After the client successfully connects, it can send messages to the server, which will then broadcast the message to all connected clients.
5. The client can also receive messages sent by the server.
6. WebSocket enables bidirectional communication, allowing clients and servers to send messages to each other at any time.
7. Implementation of Server-Sent Events (SSE):
8. In Java, SSE can be implemented using either Servlet or Spring MVC.
9. First, you need to create a Servlet or Spring MVC controller to handle client connection requests.
10. When a client initiates a connection request, the server can send an SSE event stream to the client.
11. The client can listen to the event stream and receive messages sent by the server in real time.
12. The server side can send messages to the client side at any time.

Both methods can achieve real-time message push, the choice depends on the project’s requirements and technology stack.