* This is a comma separated list of attribute names.
     */
    String KEYS_COMBINATION_MODE_ATTRIBUTE = "combine.keys";

    /**
     * This default mode for combining a DOM node during merge means that where element names match, the process will
     * try to merge the element attributes and values, rather than overriding the recessive element completely with the

        super(parent);
        this.attrib = attrib;
    }

    @Override
    public int compareChildNodePointers(NodePointer pointer1, NodePointer pointer2) {
        // should never happen because attributes have no children
        return 0;
    }

    @Override
    public Object getValue() {
        return attrib.getValue();
    }

    @Override
    public Object getBaseValue() {
        return attrib;

    public int getPosition() {
        return position;
    }

    public boolean setPosition(int position) {
        this.position = position;
        attribute = (position > 0 && position <= attributes.size()) ? attributes.get(position - 1) : null;
        return attribute != null;
    }

import org.apache.maven.artifact.versioning.VersionRange;
import org.apache.maven.project.MavenProject;

/**
 * Wraps an active project instance to be able to receive updates from its artifact without affecting the original
 * attributes of this artifact.
 *
 * TODO I think this exposes a design flaw in that the immutable and mutable parts of an artifact are in one class and

        private boolean sourceLevelSet = false;

        public void setSourceLevel(String sourceLevel) {
            if (sourceLevelSet) {
                throw new IllegalStateException("Cannot reset sourceLevel attribute; it is already set to: " + sourceLevel);
            } else if (!(USER_LEVEL.equals(sourceLevel) || GLOBAL_LEVEL.equals(sourceLevel))) {

 * or a {@code pom.xml} containing the {@code root="true"} attribute.
 */
public interface RootLocator {

    String UNABLE_TO_FIND_ROOT_PROJECT_MESSAGE = "Unable to find the root directory. "
            + "Create a .mvn directory in the root directory or add the root=\"true\""
            + " attribute on the root project's model to identify it.";

    @Nonnull

        } 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) {