A required class is missing: org.apache.maven.plugin.jar.JarMojo

Question

After I upgraded my Ubuntu to 13.10 version I reinstalled the latest Eclipse Kepler.

I have a simple JSE app. It used to work in Eclipse before and it's still working through terminal (mvn clean install), but now I'm getting an error in Eclipse:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-jar-plugin:2.3.2:jar 
(default-jar) on project files: Execution default-jar of goal org.apache.maven.plugins:maven-jar-plugin:2.3.2:jar
failed: Unable to load the mojo 'jar' in the plugin 'org.apache.maven.plugins:maven-jar-plugin:2.3.2'.
A required class is missing: org.apache.maven.plugin.jar.JarMojo

I already tried a few things:

• I checked jvm version configured in eclipse.ini: -vm /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java
• I tried 3.0.5 and 3.1.1 maven versions;
• I right-clicked the project and selected Maven->Update Project.
• I checked the java version in the project properties menu: it's pointing to /usr/lib/jvm/java-6-openjdk-amd64, although it always changes back to JavaSE-1.6(jre6) after I follow the previous step (Update Project).
• Set java source and target version to 1.6 in the maven-compiler-plugin in pom.xml configuration.
• Tried different jdk versions (openjdk6, openjdk7, oracle jdk6 and oracle jdk7);
• I also tried to download JBoss Devstudio and also cleaning workspace by deleting .metadata folder.

Unfortunately nothing worked.

This is my pom.xml:

<?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/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>br.uel.ati.util</groupId>
  <artifactId>files</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>jse-template</name>

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

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>2.4</version>
    </dependency>
  </dependencies>

  <build>
        <pluginManagement>
            <plugins>
                <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>
        </plugins>
    </pluginManagement>
</build>

  <description>Template da Diretoria de Desenvolvimento de Sistemas para bibliotecas utilizadas por projetos EJB e Web.</description>
     <organization>
    <name>Universidade Estadual de Londrina</name>
    <url>http://uel.br/ati</url>
  </organization>
</project>

Anyone know what I should try to solve this issue?

I found the solution here: How can i resolve plugin problem in maven:' Unable to load mojo'

Apparently there was a corrupted library in maven repository. I just deleted repository/org folder, download it again and updated (Maven->Update Project + F5) my maven projects inside Eclipse.

I'm still curious about why it was working by command line. Maybe a new maven repository was created when I installed it by apt-get.