msgs.add("*****************************************************************");
        msgs.add("* An aggregator Mojo is already executing in parallel build,    *");
        msgs.add("* but aggregator Mojos require exclusive access to reactor to   *");
        msgs.add("* prevent race conditions. This mojo execution will be blocked  *");
        msgs.add("* until the aggregator work is done.                            *");

 -----

Maven Compat

 Maven2 classes maintained as compatibility layer for plugins that need to keep Maven2 compatibility.

 Plugins should avoid these classes and be updated to use only Maven3 dependencies (and require Maven3): see
 {{{https://cwiki.apache.org/confluence/display/MAVEN/Plugin+migration+to+Maven3+dependencies} Plugin migration to Maven3 dependencies}}

     * create a custom {@code Type} for it.
     *
     * @param id the id of the type to retrieve
     * @return the type
     */
    @Nonnull
    @Override
    default Type require(@Nonnull String id) {
        return lookup(id).orElseThrow(() -> new IllegalArgumentException("Unknown extensible enum value '" + id + "'"));
    }

#*      *##set ( $spdx = 'EPL-1.0' )
#*    *##elseif ( $license.url.contains( "www.apache.org/licenses/LICENSE-2.0" ) )
#*      *##set ( $spdx = 'Apache-2.0' )
#*    *##else
#*      *### unrecognized license will require analysis to know obligations
#*      *##set ( $spdx = 'unrecognized' )
#*    *##end
#*    *###
#*    *### fix project urls that are wrong in pom
#*    *##if ( $project.url.startsWith( "http://www.eclipse.org/sisu/" ) )

contribution quickly and easily:

 - [ ] Make sure there is a [JIRA issue](https://issues.apache.org/jira/browse/MNG) filed
       for the change (usually before you start working on it).  Trivial changes like typos do not
       require a JIRA issue. Your pull request should address just this issue, without
       pulling in other changes.
 - [ ] Each commit in the pull request should have a meaningful subject line and body.

/**
 * Provides backwards compatibility with Maven 3.2.3 and earlier. Clients that do not require compatibility with Maven
 * 3.2.3 and earlier are encouraged to use {@link JavaToolchainImpl}.
 * <strong>Note:</strong> This is an internal component whose interface can change without prior notice.
 *
 * @deprecated clients that do not require compatibility with Maven 3.2.3 and earlier should link to
 *             {@link JavaToolchainImpl} instead.

    the same other JDK instance without hardcoding absolute paths into the {@code pom.xml}
    and without configuring every plugin that require path to JDK tools.</p>

    @see <a href="/guides/mini/guide-using-toolchains.html">Guide to Using Toolchains</a>
    ]]></description>

  <defaults>
    <default>
      <key>package</key>

                        throw new IllegalStateException(e);
                    }
                }
            }
            throw new IllegalArgumentException("The use of session scoped proxies require "
                    + "a org.eclipse.sisu.Typed or javax.enterprise.inject.Typed annotation");
        }
    }

    /**
     * A provider wrapping an existing provider with a cache

import org.apache.maven.api.annotations.Nonnull;

public interface ExtensibleEnumRegistry<T extends ExtensibleEnum> extends Service {
    @Nonnull
    Optional<T> lookup(@Nonnull String id);

    @Nonnull
    default T require(@Nonnull String id) {
        return lookup(id).orElseThrow(() -> new IllegalArgumentException("Unknown extensible enum value '" + id + "'"));
    }

            }
        }
    }

    @Override
    public ArtifactHandler getArtifactHandler(String id) {
        return allHandlers.computeIfAbsent(id, k -> {
            Type type = typeRegistry.require(id);
            return new DefaultArtifactHandler(
                    id,
                    type.getExtension(),
                    type.getClassifier(),
                    null,
                    null,