<url>http://plexus.codehaus.org/plexus-utils</url>
  <build>
    <plugins>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <configuration>
          <!-- surefire requires plexus-utils to be jdk 1.3 compatible -->
          <source>1.3</source>
          <target>1.3</target>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>

  <url>http://plexus.codehaus.org/plexus-utils</url>
  <build>
    <plugins>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <configuration>
          <!-- surefire requires plexus-utils to be jdk 1.3 compatible -->
          <source>1.3</source>
          <target>1.3</target>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>

    /**
     * default phase to bind your mojo.
     * @return the default phase
     */
    @Nonnull
    String defaultPhase() default "";

    /**
     * does your mojo requires a project to be executed?
     * @return requires a project
     */
    boolean projectRequired() default true;

    /**
     * if the Mojo uses the Maven project and its child modules.

- version range violation
- circular dependency
- artifact missing
- artifact retrieval exception
- md5 checksum doesn't match for local artifact, need to redownload this
- POM doesn't exist for a goal that requires one
- parent POM missing (in both the repository + relative path)
- component not found

Plugins:
- plugin metadata missing
- plugin metadata retrieval problem
- plugin artifact missing

        try {
            if (buildExecutionRequiresProject(session) && projectIsNotPresent(session)) {
                throw new MissingProjectException("The goal you specified requires a project to execute"
                        + " but there is no POM in this directory (" + session.getExecutionRootDirectory() + ")."
                        + " Please verify you invoked Maven from the correct directory.");

                <!--
                Checks that the version of user's maven installation is 3.0.4,
                the JDK is 1.5+, no non-standard repositories are specified in
                the project, requires only release versions of dependencies of other artifacts.
                -->
                <artifactId>maven-enforcer-plugin</artifactId>
                <version>1.4</version>
                <executions>

            // TODO Should this be changed for MNG-6754 too?
            snapshot.setTimestamp(getDeploymentTimestamp());

            // we update the build number anyway so that it doesn't get lost. It requires the timestamp to take effect
            try {
                int buildNumber = resolveLatestSnapshotBuildNumber(artifact, localRepository, remoteRepository);

                snapshot.setBuildNumber(buildNumber + 1);

Minimum Element-Set for a Project POM

  In order to furnish a basic set of information which we need to distinguish one
  project from another, maven requires a minimum set of elements to be specified
  in each project's pom.xml.

   - [modelVersion] tells maven which version of the object model this project
       is compliant with (to support future legacy concerns)

        } else if (project.getModel().getDelegate().isRoot()) {
            throw new IllegalStateException(
                    "The use of the root attribute on the model requires the buildconsumer feature to be active");
        }
    }

    TransformedArtifact createConsumerPomArtifact(
            MavenProject project, Path consumer, RepositorySystemSession session) {

        }
    }

    @Override
    public void mojoSkipped(ExecutionEvent event) {
        if (logger.isWarnEnabled()) {
            init();
            logger.warn(
                    "Goal '{}' requires online mode for execution but Maven is currently offline, skipping",
                    event.getMojoExecution().getGoal());
        }
    }

    /**