public class MavenDependencyKey {
    private static final String KEY_SEPARATOR = ":";
    private final String groupId;
    private final String artifactId;
    private final String type;
    private final String classifier;

    public MavenDependencyKey(String groupId, String artifactId, String type, String classifier) {
        this.groupId = groupId;
        this.artifactId = artifactId;
        this.type = type;
        this.classifier = classifier;

    }

    private Plugin createPlugin(String groupId, String artifactId, String version) {
        Plugin plugin = new Plugin();
        plugin.setGroupId(groupId);
        plugin.setArtifactId(artifactId);
        plugin.setVersion(version);
        return plugin;
    }

    private Extension createExtension(String groupId, String artifactId, String version) {
        Extension extension = new Extension();

<project>
  <modelVersion>4.0.0</modelVersion>
  <packaging>pom</packaging>
  <groupId>org.gradle</groupId>
  <artifactId>test</artifactId>
  <version>0</version>

  <modules>
    <module>commons</module>
  </modules>
</project>
"""

        temp.file("commons/pom.xml").text = """\
<project>
  <parent>
    <groupId>org.gradle</groupId>
    <artifactId>test</artifactId>
    <version>0</version>
  </parent>

    <modelVersion>4.1.0</modelVersion>

    <groupId>test</groupId>
    <artifactId>test</artifactId>
    <version>0.1-SNAPSHOT</version>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>test</groupId>
                <artifactId>mydep</artifactId>
                <version>0.2</version>
            </dependency>

            String version,
            String message) {
        this.artifact = Objects.requireNonNull(artifact, "artifact cannot be null");
        this.groupId = (groupId != null && !groupId.isEmpty()) ? groupId : null;
        this.artifactId = (artifactId != null && !artifactId.isEmpty()) ? artifactId : null;
        this.classifier = (classifier != null && !classifier.isEmpty()) ? classifier : null;

    protected Class<? extends Group> typeOfSelectedEntity() {
        return Group.class;
    }

    @Override
    protected Class<Group> typeOfHandlingEntity() {
        return Group.class;
    }

    @Override
    protected Class<GroupCB> typeOfHandlingConditionBean() {
        return GroupCB.class;
    }

    public ListResultBean<Group> selectList(CBCall<GroupCB> cbLambda) {

<project>
  <modelVersion>4.0.0</modelVersion>

  <groupId>test</groupId>
  <artifactId>invalid</artifactId>
  <version>0.0.1-SNAPSHOT</version>

  <repositories>
    <repository>
      <id>central</id>
      <url>file:src/test/remote-repo</url>
    </repository>
  </repositories>

  <dependencies>
    <dependency>
      <!-- groupId deliberately missing -->
      <artifactId>b</artifactId>
      <version>0.1</version>

    <modelVersion>4.0.0</modelVersion>
    <groupId>util</groupId>
    <artifactId>enforcerExample</artifactId>
    <version>1.0</version>
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.6</version>
        </dependency>

          </plugin>
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-pmd-plugin</artifactId>
          </plugin>
          <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>cobertura-maven-plugin</artifactId>
          </plugin>
          <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>taglist-maven-plugin</artifactId>

        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-pmd-plugin</artifactId>
      </plugin>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>cobertura-maven-plugin</artifactId>
      </plugin>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>taglist-maven-plugin</artifactId>