Why messaging matters in Spring Boot - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to send a message using Spring Boot's messaging template.

Spring Boot

messagingTemplate.[1]("topicName", "Hello World");

Drag options to blanks, or click blank then click option'

AconvertAndSend

Bconnect

Clisten

Dreceive

Attempts:

3 left

💡 Hint

Common Mistakes

Using receive instead of convertAndSend

Using listen which is for receiving messages

The convertAndSend method is used to send messages to a destination in Spring Boot messaging.

2fill in blank

medium

Complete the code to define a message listener method in a Spring Boot component.

Spring Boot

@[1]("/topic/greetings")
public void receiveMessage(String message) {
    System.out.println(message);
}

Drag options to blanks, or click blank then click option'

ASendMapping

BSubscribeMapping

CMessageMapping

DEventListener

Attempts:

3 left

💡 Hint

Common Mistakes

Using @SendMapping which is not a valid annotation

Confusing with @EventListener which is for events

The @MessageMapping annotation maps incoming messages to the method in Spring Boot messaging.

3fill in blank

hard

Fix the error in the method to correctly send a message asynchronously.

Spring Boot

public void sendAsyncMessage(String destination, String msg) {
    messagingTemplate.[1](destination, msg);
}

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AsendAsync

BconvertAndSend

CsendMessage

DasyncSend

Attempts:

3 left

💡 Hint

Common Mistakes

Using sendAsync which does not exist

Using sendMessage which is not a Spring method

The convertAndSend method converts the message and sends it asynchronously in Spring Boot messaging.

4fill in blank

hard

Fill both blanks to create a message listener that listens to a topic and sends a response.

Spring Boot

@[1]("/app/hello")
@SendTo("/topic/greetings")
public String greet(String name) {
    return "Hello, " + [2] + "!";
}

Drag options to blanks, or click blank then click option'

AMessageMapping

Bname

CSendMapping

Dmessage

Attempts:

3 left

💡 Hint

Common Mistakes

Using @SendMapping which is invalid

Using wrong parameter name in return statement

The method listens to messages mapped by @MessageMapping and uses the parameter name to create a greeting.

5fill in blank

hard

Fill all three blanks to configure a simple message broker in Spring Boot.

Spring Boot

@Override
public void configureMessageBroker([1] registry) {
    registry.[2]("/topic");
    registry.[3]("/app");
}

Drag options to blanks, or click blank then click option'

AMessageBrokerRegistry

BenableSimpleBroker

CsetApplicationDestinationPrefixes

DMessageMapping

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong parameter type

Confusing method names

Missing prefixes

The method parameter is MessageBrokerRegistry. The enableSimpleBroker sets the topic prefix, and setApplicationDestinationPrefixes sets the application prefix.