[FIXED] Java class version error when packaging Spring boot AWS function with Maven

Issue

I am trying to build a Spring boot project for AWS lambda and getting a Java class version error. A dependency class was compiled using Java 17 and I'm building with Java 11. I need to stick to Java 11, as that's the latest version supported by AWS lambda.

Maven call:

docker run -it --rm --name aws-lambda-app -v maven-repo:/root/.m2 -v ${pwd}:/usr/src/aws-lambda-app -w /usr/src/aws-lambda-app maven:3.8.6-openjdk-11 ./mvnw clean -DskipTests package -X

Full Error:

org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.10.1:compile (default-compile) on project tracker: Compilation failure
Could not load processor class file due to 'org/springframework/boot/configurationprocessor/ConfigurationMetadataAnnotationProcessor has been compiled by a more recent version of the Java Runtime (class file version 61.0), this version of the Java Runtime only recognizes class file versions up to 55.0'.

My pom.xml:

My pom.xml is based on this example. It is slightly altered to include java.version and maven.compiler.release in properties.

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd"
>
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.0.0-SNAPSHOT</version>
        <relativePath/>
    </parent>
    <groupId>com.sample-apps</groupId>
    <artifactId>aws-lambda-app</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>Sample AWS Lambda APP</name>
    <description
        >...</description
    >
    <properties>
        <java.version>11</java.version>
        <maven.compiler.release>11</maven.compiler.release>
        <!-- <maven.compiler.source>11</maven.compiler.source> -->
        <!-- <maven.compiler.target>11</maven.compiler.target> -->
        <aws-lambda-events.version>3.9.0</aws-lambda-events.version>
        <wrapper.version>1.0.27.RELEASE</wrapper.version>
        <spring-cloud-function.version
            >4.0.0-SNAPSHOT</spring-cloud-function.version
        >
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-function-adapter-aws</artifactId>
        </dependency>
        <dependency>
            <groupId>com.amazonaws</groupId>
            <artifactId>aws-lambda-java-events</artifactId>
            <version>${aws-lambda-events.version}</version>
        </dependency>
        <dependency>
            <groupId>com.amazonaws</groupId>
            <artifactId>aws-lambda-java-core</artifactId>
            <version>1.1.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-function-dependencies</artifactId>
                <version>${spring-cloud-function.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-deploy-plugin</artifactId>
                <configuration>
                    <skip>true</skip>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <dependencies>
                    <dependency>
                        <groupId>org.springframework.boot.experimental</groupId>
                        <artifactId>spring-boot-thin-layout</artifactId>
                        <version>${wrapper.version}</version>
                    </dependency>
                </dependencies>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.2.4</version>
                <configuration>
                    <createDependencyReducedPom
                        >false</createDependencyReducedPom
                    >
                    <shadedArtifactAttached>true</shadedArtifactAttached>
                    <shadedClassifierName>aws</shadedClassifierName>
                    <release>11</release>                    

                </configuration>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </pluginRepository>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </pluginRepository>
    </pluginRepositories>
</project>

Solution

According to this Github issue, branch 3.2.x should be used for my scenario. I updated my pom.xml based on the example, and I was able to build my project.

Answered By - Shroder
Answer Checked By - Katrina (JavaFixing Volunteer)