Problemas com jetty:run

Bem, já tententei de tudo com esse jetty. Mudei porta, criei goals, mudei o jetty de versão, mudei o java, jdk do 5 ao 8... Eu só sei que estes arquivos que o jetty:run está procurando, não estão vindo para o repositório local. Se alguem puder me dar uma luz para prosseguir em diante. Desde já agradeço.

O Log todo nem coube aqui :

[ERROR] Failed to execute goal org.eclipse.jetty:jetty-maven-plugin:9.4.2.v20170220:run (default-cli) on project lojaweb: Execution default-cli of goal org.eclipse.jetty:jetty-maven-plugin:9.4.2.v20170220:run failed: Unable to load the mojo 'run' in the plugin 'org.eclipse.jetty:jetty-maven-plugin:9.4.2.v20170220' due to an API incompatibility: org.codehaus.plexus.component.repository.exception.ComponentLookupException: org/eclipse/jetty/maven/plugin/JettyRunMojo : Unsupported major.minor version 52.0 [ERROR] ----------------------------------------------------- [ERROR] realm = plugin>org.eclipse.jetty:jetty-maven-plugin:9.4.2.v20170220 [ERROR] strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy [ERROR] urls[0] = file:/C:/Users/J·nior/.m2/repository/org/eclipse/jetty/jetty-maven-plugin/9.4.2.v20170220/jetty-maven-plugin-9.4.2.v20170220.jar

pom.xml

<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>
    <groupId>br.com.alura.maven</groupId>
    <artifactId>lojaweb</artifactId>
    <packaging>war</packaging>
    <version>1.0.0-SNAPSHOT</version>
    <name>lojaweb Maven Webapp</name>
    <url>http://maven.apache.org</url>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <finalName>lojaweb</finalName>

        <plugins>    
            <plugin>

                <groupId>org.eclipse.jetty</groupId>
                <artifactId>jetty-maven-plugin</artifactId>
                <version>9.4.2.v20170220</version>

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

    <properties>
        <project.build.sourceEncoding> UTF-8 </project.build.sourceEncoding>
    </properties>

</project>