<build>
        <plugins>
            <plugin>
                <artifactId>maven-enforcer-plugin</artifactId>
                <version>1.0</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>enforce</goal>
                        </goals>
                        <id>enforce</id>
                        <configuration>
                            <rules>

    <defaultGoal>install</defaultGoal>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-enforcer-plugin</artifactId>
        <executions>
          <execution>
            <id>enforce-java</id>
            <goals>
              <goal>enforce</goal>
            </goals>
            <configuration>
              <rules>
                <requireMavenVersion>

  <build>

    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-enforcer-plugin</artifactId>
        <version>1.0-alpha-3</version>
        <executions>
          <execution>
            <id>enforce-java</id>
            <goals>
              <goal>enforce</goal>
            </goals>
            <configuration>
              <rules>
                <requireMavenVersion>

notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with
the distribution.

Neither the name of JLine nor the names of its contributors
may be used to endorse or promote products derived from this
software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,

  documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holders nor the names of its
  contributors may be used to endorse or promote products derived from
  this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

   documentation and/or other materials provided with the distribution.

3. Neither the name of the copyright holders nor the names of its
   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

            throws TransferFailedException, ResourceDoesNotExistException;

    void getArtifact(
            Artifact artifact,
            List<ArtifactRepository> remoteRepositories,
            TransferListener transferListener,
            boolean force)
            throws TransferFailedException, ResourceDoesNotExistException;

     */
    boolean required() default false;

    /**
     * Specifies that this parameter cannot be configured directly by the user (as in the case of POM-specified
     * configuration). This is useful when you want to force the user to use common POM elements rather than plugin
     * configurations, as in the case where you want to use the artifact's final name as a parameter. In this case, you

     * @param problem The problem whose location should be formatted, must not be {@code null}.
     * @param projectId The {@code <groupId>:<artifactId>:<version>} of the corresponding project, may be {@code null}
     *            to force output of model id and source.
     * @return The formatted problem location or an empty string if unknown, never {@code null}.
     */
    public static String formatLocation(ModelProblem problem, String projectId) {

        if (proxies == null) {
            proxies = new ArrayList<>();
        }

        return proxies;
    }

    //
    // Used by Tycho and will break users and force them to upgrade to Maven 3.1 so we should really leave
    // this here, possibly indefinitely.
    //
    public ArtifactResolutionRequest setCache(RepositoryCache cache) {
        return this;
    }