if (propValue.startsWith("!")) {
                reverseValue = true;
                propValue = propValue.substring(1);
            }

            // we have a value, so it has to match the system value...
            return reverseValue != propValue.equals(sysValue);
        } else {
            return reverseName != (sysValue != null && !sysValue.isEmpty());
        }
    }

    @Override

        }

        return layout;
    }

    /**
     * In the future, the legacy system might encounter repository types for which no layout components exists because
     * the actual communication with the repository happens via a repository connector. As a minimum, the legacy system
     * needs to retain the id of this layout so that the content type of the remote repository can still be accurately

        return request.getUserProperties();
    }

    /**
     * Gets the system properties to use for interpolation and profile activation. The system properties are collected
     * from the runtime environment like {@link System#getProperties()} and environment variables.
     *
     * @return The system properties, never {@code null}.
     */
    public Properties getSystemProperties() {

  <url>http://maven.apache.org/maven2/</url>
  <issueManagement>
    <system>jira</system>
    <url>http://jira.codehaus.org/browse/MNG</url>
  </issueManagement>
  <ciManagement>
    <system>continuum</system>
    <notifiers>
      <notifier>
        <configuration>
          <address>******@****.***</address>
        </configuration>

      <archive>http://archive.plexus.codehaus.org/scm</archive>
    </mailingList>
  </mailingLists>
  <issueManagement>
    <system>JIRA</system>
    <url>http://jira.codehaus.org/browse/PLX</url>
  </issueManagement>

  <distributionManagement>
    <repository>
      <id>codehaus.org</id>
      <name>Plexus Central Repository</name>

        if (artifact == null) {
            return;
        }

        if (Artifact.SCOPE_SYSTEM.equals(artifact.getScope())) {
            File systemFile = artifact.getFile();

            if (systemFile == null) {
                throw new ArtifactNotFoundException("System artifact: " + artifact + " has no file attached", artifact);
            }

            if (!systemFile.exists()) {

/**
 * Shared methods of the repository metadata handling.
 *
 */
@Deprecated
public abstract class AbstractRepositoryMetadata implements RepositoryMetadata {
    private static final String LS = System.lineSeparator();

    private Metadata metadata;

    protected AbstractRepositoryMetadata(Metadata metadata) {
        this.metadata = metadata;
    }

    public String getRemoteFilename() {

    private Map<String, Profile> profilesById = new LinkedHashMap<>();

    private Properties requestProperties;

    /**
     * @deprecated without passing in the system properties, the SystemPropertiesProfileActivator will not work
     *             correctly in embedded environments.
     */
    @Deprecated
    public DefaultProfileManager(PlexusContainer container) {

import org.apache.maven.api.services.model.ProfileActivationContext;
import org.apache.maven.api.services.model.ProfileActivator;

/**
 * Determines profile activation based on the operating system of the current runtime platform.
 *
 * @see ActivationOS
 */
@Named("os")
@Singleton
public class OperatingSystemProfileActivator implements ProfileActivator {

        MojoExecution exec = newMojoExecution(session);

        Object result =
                new PluginParameterExpressionEvaluatorV4(session, null, exec).evaluate("${mojo.plugin.descriptor}");

        System.out.println("Result: " + result);

        assertSame(
                exec.getPlugin().getDescriptor(),
                result,
                "${mojo.plugin.descriptor} expression does not return plugin descriptor.");