Everything You Need to Know about Web Socket in Spring Boot

If you are a developer looking to create a real-time web application, you have probably come across the term “Web Socket in Spring Boot”. This technology has become increasingly popular in recent years, as it allows for real-time communication between the server and client. In this article, we will explain everything you need to know about Web Socket in Spring Boot, from its definition to its implementation.

What is Web Socket?

Web Socket is a protocol that provides full-duplex communication channels over a single TCP connection. This means that the server can send information to the client, and the client can send information back to the server, in real-time. Web Socket is particularly useful for real-time web applications, such as chat applications or online games.

What is Spring Boot?

Spring Boot is a popular Java framework for building web applications. It is designed to make it easy to create stand-alone, production-grade Spring-based applications that you can “just run”. Spring Boot provides a range of features to help you get started with your application quickly, including an embedded server, auto-configuration, and a range of starter dependencies.

What is Web Socket in Spring Boot?

Web Socket in Spring Boot is simply the implementation of Web Socket in a Spring Boot application. Spring Boot provides a range of features to make it easy to implement Web Socket in your application, including support for the STOMP protocol (which is often used with Web Socket), and a range of Spring Boot starter dependencies for Web Socket.

How to Implement Web Socket in Spring Boot

Implementing Web Socket in Spring Boot is relatively straightforward. Here are the basic steps:

1. Add the Spring Boot Web Socket starter dependency to your project
2. Create a configuration class to configure Web Socket
3. Create a class to handle Web Socket messages
4. Create a class to handle Web Socket subscriptions

Add the Spring Boot Web Socket starter dependency to your project

To add the Spring Boot Web Socket starter dependency to your project, you need to add the following dependency to your pom.xml file:

<dependency>

    <groupId>org.springframework.boot</groupId>

    <artifactId>spring-boot-starter-websocket</artifactId>

</dependency>

Create a configuration class to configure Web Socket

To configure Web Socket in your Spring Boot application, you need to create a configuration class that extends the “AbstractWebSocketMessageBrokerConfigurer” class. Here is an example of a basic configuration class:

@Configuration

@EnableWebSocketMessageBroker

public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {

    @Override

    public void configureMessageBroker(MessageBrokerRegistry config) {

        config.enableSimpleBroker(“/topic”);

        config.setApplicationDestinationPrefixes(“/app”);

    }

    @Override

    public void registerStompEndpoints(StompEndpointRegistry registry) {

        registry.addEndpoint(“/ws”).withSockJS();

    }

}

This configuration class enables the STOMP protocol, configures a simple message broker, and registers a STOMP endpoint.

Create a class to handle Web Socket messages

To handle Web Socket messages in your Spring Boot application, you need to create a class that implements the “WebSocketHandler” interface. Here is an example of a basic message handling class:

@Component

public class MyWebSocketHandler implements WebSocketHandler {

    @Override

    public void afterConnectionEstablished(WebSocketSession session) throws Exception {

        // Handle connection established event

    }

    @Override

    public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception {

        // Handle message received event

    }

    @Override

    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {

        // Handle transport error event

    }

    @Override

    public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {

        // Handle connection closed event

    }

    @Override

    public boolean supportsPartialMessages() {

        return false;

    }

}

This message handling class defines methods to handle various Web Socket events, such as connection established, message received, transport error, connection closed, and partial messages.

Create a class to handle Web Socket subscriptions

To handle Web Socket subscriptions in your Spring Boot application, you need to create a class that extends the “AbstractWebSocketMessageBrokerConfigurer” class. Here is an example of a basic subscription handling class:

@Component

public class MySubscriptionHandler extends AbstractWebSocketMessageBrokerConfigurer {

    @Override

    public void configureMessageBroker(MessageBrokerRegistry config) {

        config.enableSimpleBroker(“/topic”);

        config.setApplicationDestinationPrefixes(“/app”);

    }

    @Override

    public void registerStompEndpoints(StompEndpointRegistry registry) {

        registry.addEndpoint(“/ws”).withSockJS();

    }

}

This subscription handling class defines the same methods as the configuration class, but with a different implementation. It enables the STOMP protocol, configures a simple message broker, and registers a STOMP endpoint.

FAQ

What are the benefits of using Web Socket in Spring Boot?

The main benefits of using Web Socket in Spring Boot are:

• Real-time communication: Web Socket allows for real-time communication between the server and client, which is particularly useful for real-time web applications.
• Scalability: Web Socket is designed to be scalable, so you can handle a large number of concurrent connections.
• Efficiency: Web Socket is designed to be efficient, so you can handle a large number of messages with minimal overhead.

What are the disadvantages of using Web Socket in Spring Boot?

The main disadvantages of using Web Socket in Spring Boot are:

• Complexity: Web Socket can be complex to implement, particularly if you are new to the technology.
• Compatibility: Web Socket is not supported by all browsers, so you may need to provide fallback options for users who are using older browsers.
• Server load: Web Socket can put a significant load on your server, particularly if you are handling a large number of concurrent connections.

What are some examples of real-time web applications that use Web Socket in Spring Boot?

Some examples of real-time web applications that use Web Socket in Spring Boot include:

• Chat applications
• Online games
• Real-time dashboards
• Collaborative editing tools

Is Web Socket in Spring Boot the only technology for real-time web applications?

No, there are other technologies for real-time web applications, such as long polling and server-sent events. However, Web Socket is generally considered to be the most efficient and scalable technology for real-time web applications.