+ " is missing.",
                    dependency.getLocation(""));
            return null;
        }

        String imported = groupId + ':' + artifactId + ':' + version;

        if (importIds.contains(imported)) {
            StringBuilder message =
                    new StringBuilder("The dependencies of type=pom and with scope=import form a cycle: ");

            for (Map.Entry<String, ClassLoader> entry : foreignImports.entrySet()) {
                ClassLoader importedRealm = entry.getValue();
                String imp = entry.getKey();

                logger.debug("  Imported: {} < {}", imp, getId(importedRealm));

                classRealm.importFrom(importedRealm, imp);
            }
        }

        if (parentImports != null && !parentImports.isEmpty()) {

                        problems.add(
                                Severity.WARNING,
                                Version.V40,
                                "Ignored POM import for: " + toString(dependency) + " as already imported "
                                        + toString(present) + ".  Add a the conflicting managed dependency directly "
                                        + "to the dependencyManagement section of the POM.");

          <version>1.0.0+</version>
          <type>String</type>
          <description>
            Specifies an alias which can be used to configure this parameter from the POM.
            This is primarily useful to improve user-friendliness, where Mojo field names are not intuitive to the
            user or are otherwise not conducive to configuration via the POM.
          </description>
        </field>
        <field>

import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.maven.api.model.Model;

/**
 * Holds all Models that are known to the reactor. This allows the project builder to resolve imported Models from the
 * reactor when building another project's effective model.
 *
 */
class ReactorModelPool {
    private final Map<GAKey, Set<Model>> modelsByGa = new ConcurrentHashMap<>();

            for (String extension : checksums.keySet()) {
                // TODO shouldn't need a file intermediary - improve wagon to take a stream
                File temp = File.createTempFile("maven-artifact", null);
                temp.deleteOnExit();
                byte[] bytes = sums.get(extension).getBytes(StandardCharsets.UTF_8);

                            errOn30,
                            Version.V20,
                            prefix + prefix2 + "classifier",
                            key,
                            "must be empty, imported POM cannot have a classifier.",
                            dependency);
                }
            } else if ("system".equals(dependency.getScope())) {

        verifier.verify(logger, calls(1)).debug("Importing foreign packages into class realm {}", "maven.api");
        verifier.verify(logger, calls(1)).debug("  Imported: {} < {}", "group1:artifact1", "test");
        verifier.verify(logger, calls(1)).debug("  Excluded: {}", "group1:artifact2:ext:classifier1:null");
        verifier.verify(logger, calls(1))