[FIXED] How to fix "A SockJsMessageCodec is required but not available"

Issue

My app. is a server written in Kotlin that uses Spring Boot, web sockets and Stomp. When the browser sends a web socket request to the server, the server logs:

2022-05-18 15:44:55.394 ERROR 1697157 --- [nio-8080-exec-8] s.w.s.s.t.s.WebSocketServerSockJsSession : Broken data received. Terminating WebSocket connection abruptly

java.lang.IllegalStateException: A SockJsMessageCodec is required but not available: Add Jackson to the classpath, or configure a custom SockJsMessageCodec.

There are plenty of search hits on the phrase A SockJsMessageCodec ... but none work for me.

I've experimented with various versions of Spring Boot and Jackson, and specifying <repositories> explicitly but clearly I am missing the point.

Here is my POM: what am I doing wrong?

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.3</version>
        <relativePath/>
    </parent>
    <groupId>{omitted here}</groupId>
    <artifactId>kitten</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>{omitted here} kitten</name>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <kotlin.version>1.6.10</kotlin.version>
        <kotlin.code.style>official</kotlin.code.style>
        <junit.version>5.8.2</junit.version>
        <aws.version>2.17.174</aws.version>
        <Jackson.version>2.13.3</Jackson.version>
        <Spring.version>2.6.3</Spring.version>
        <Spring.other.version>5.3.19</Spring.other.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
            <version>${Spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jdbc</artifactId>
            <version>${Spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-websocket</artifactId>
            <version>9.0.56</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>${Spring.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-test -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-test</artifactId>
            <version>${Spring.version}</version>
            <scope>test</scope>
            <!-- scope>test</scope -->
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-orm -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>${Spring.other.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework.data/spring-data-jpa -->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-jpa</artifactId>
            <version>2.6.4</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.25</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-commons</artifactId>
            <version>2.6.4</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <version>${Spring.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>javax.persistence</groupId>
            <artifactId>javax.persistence-api</artifactId>
            <version>2.2</version>
        </dependency>
        <!--https://search.maven.org/remotecontent?filepath=org/hibernate/hibernate-core/5.5.7.Final/hibernate-core-5.5.7.Final.jar-->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.6.8.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>5.6.8.Final</version>
        </dependency>
        <dependency>
            <groupId>org.mariadb.jdbc</groupId>
            <artifactId>mariadb-java-client</artifactId>
            <scope>runtime</scope>
            <version>2.7.5</version>
        </dependency>
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>webjars-locator-core</artifactId>
            <version>0.48</version>
        </dependency>
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>sockjs-client</artifactId>
            <!-- has to be 1.0.0 for compatibility with Azure -->
            <version>1.5.1</version>
        </dependency>
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>stomp-websocket</artifactId>
            <version>2.3.3</version>
        </dependency>
        <dependency>
            <groupId>com.stripe</groupId>
            <artifactId>stripe-java</artifactId>
            <version>20.116.0</version>
        </dependency>
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-storage-file-share</artifactId>
            <version>12.12.1</version>
        </dependency>
        <dependency>
            <groupId>com.jcraft</groupId>
            <artifactId>jsch</artifactId>
            <version>0.1.55</version>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlinx</groupId>
            <artifactId>kotlinx-coroutines-core</artifactId>
            <version>1.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-stdlib-jdk8</artifactId>
            <version>${kotlin.version}</version>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-test-junit</artifactId>
            <version>1.6.21</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-reflect</artifactId>
            <version>${kotlin.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter -->
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter-api -->
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-websocket</artifactId>
            <version>${Spring.other.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-messaging</artifactId>
            <version>${Spring.other.version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>${Jackson.version}</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson</groupId>
            <artifactId>jackson-bom</artifactId>
            <version>${Jackson.version}</version>
            <type>pom</type>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>${Jackson.version}</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.13.2.2</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${Spring.other.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/commons-net/commons-net -->
        <dependency>
            <groupId>commons-net</groupId>
            <artifactId>commons-net</artifactId>
            <version>3.8.0</version>
        </dependency>
        <dependency>
            <groupId>software.amazon.awssdk</groupId>
            <artifactId>s3</artifactId>
            <version>${aws.version}</version>
        </dependency>
        <dependency>
            <groupId>software.amazon.awssdk</groupId>
            <artifactId>sesv2</artifactId>
            <version>${aws.version}</version>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-stdlib</artifactId>
            <version>${kotlin.version}</version>
        </dependency>
    </dependencies>
    <build>
        <sourceDirectory>src/main/kotlin</sourceDirectory>
        <testSourceDirectory>src/test/kotlin</testSourceDirectory>
        <pluginManagement>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
                <plugin>
                    <groupId>org.jetbrains.kotlin</groupId>
                    <artifactId>kotlin-maven-plugin</artifactId>
                    <version>1.6.10</version>
                    <executions>
                        <execution>
                            <id>compile</id>
                            <phase>compile</phase>
                            <goals>
                                <goal>compile</goal>
                            </goals>
                        </execution>
                        <execution>
                            <id>test-compile</id>
                            <phase>test-compile</phase>
                            <goals>
                                <goal>test-compile</goal>
                            </goals>
                        </execution>
                    </executions>
                </plugin>
            </plugins>
        </pluginManagement>
        <plugins>
            <plugin>
                <groupId>org.jetbrains.kotlin</groupId>
                <artifactId>kotlin-maven-plugin</artifactId>
                <version>${kotlin.version}</version>
                <executions>
                    <execution>
                        <id>compile</id>
                        <phase>compile</phase>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>test-compile</id>
                        <phase>test-compile</phase>
                        <goals>
                            <goal>test-compile</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <jvmTarget>1.8</jvmTarget>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>```

Solution

Remove all your Jackson dependencies except jackson-databind and change it to this:

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>${Jackson.version}</version>
</dependency>

Answered By - dekkard
Answer Checked By - Marilyn (JavaFixing Volunteer)