}

  /**
   * If a value is present in {@code optional}, returns a stream containing only that element,
   * otherwise returns an empty stream.
   *
   * <p><b>Java 9 users:</b> use {@code optional.stream()} instead.
   */
  @Beta
  @InlineMe(replacement = "optional.stream()")
  @InlineMeValidationDisabled("Java 9+ API only")
  public static <T> Stream<T> stream(java.util.Optional<T> optional) {

      description: What does the feature currently do?
    validations:
      required: true

  - type: textarea
    attributes:
      label: Desired Behavior
      description: What do you want it to do instead?
    validations:
      required: true

  - type: markdown
    attributes:
      value: >
        Did you *actually* encounter the need for this enhancement in a real-world scenario, or does

import java.util.Date;

/**
 * Describes a set of policies for a repository to use under certain conditions.
 *
 * @deprecated Avoid use of this type, if you need access to local repository use repository system session instead.
 */
@Deprecated
public class ArtifactRepositoryPolicy {
    public static final String UPDATE_POLICY_NEVER = "never";

    public static final String UPDATE_POLICY_ALWAYS = "always";

 * as desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator
 * pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingBlockingQueue}.
 *
 * @author Raimundo Mirisola

import java.io.InputStream;
import java.nio.charset.StandardCharsets;

/**
 * Wraps an ordinary {@link CharSequence} as a source.
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services} instead
 */
@Deprecated(since = "4.0.0")
public class StringSource implements Source {
    private final String content;

    private final String location;

    private final int hashCode;

    /**

import org.eclipse.aether.RepositoryCache;
import org.eclipse.aether.RepositorySystemSession;

/**
 * A model builder cache backed by the repository system cache.
 *
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */
@Deprecated(since = "4.0.0")
class DefaultModelCache implements ModelCache {

    private final RepositorySystemSession session;

    private final RepositoryCache cache;

import org.apache.maven.plugin.descriptor.PluginDescriptor;
import org.apache.maven.project.MavenProject;

/**
 */
public class MojoExecutorStub extends MojoExecutor { // This is being lazy instead of making interface

    protected final List<MojoExecution> executions = Collections.synchronizedList(new ArrayList<>());

    public MojoExecutorStub() {
        super(null, null, null, null, null, null);
    }

 * a regular priority queue, the methods {@link #peekLast}, {@link #pollLast} and {@link
 * #removeLast} are also provided, to act on the <i>greatest</i> element in the queue instead.
 *
 * <p>A min-max priority queue can be configured with a maximum size. If so, each time the size of
 * the queue exceeds that value, the queue automatically removes its greatest element according to

import org.apache.maven.settings.building.SettingsProblemCollector;

/**
 * Validate a model settings
 *
 * @deprecated since 4.0.0, use {@code org.apache.maven.impl.DefaultSettingsValidator} instead
 */
@Deprecated(since = "4.0.0")
public interface SettingsValidator {

    /**
     * Validate the specified settings.
     *
     * @param settings The settings to validate, must not be {@code null}.

/**
 * Handles serialization of toolchains into some kind of textual format like XML.
 *
 * @deprecated since 4.0.0, use {@code org.apache.maven.api.services.xml.ToolchainsXmlFactory} instead
 */
@Deprecated(since = "4.0.0")
public interface ToolchainsWriter {

    /**
     * Writes the supplied toolchains to the specified character writer. The writer will be automatically closed before