*
 * <p>The {@code toString} method is forwarded to the delegate. Although this class does not
 * implement {@link Serializable}, a serializable subclass may be created since this class has a
 * parameter-less constructor.
 *
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingObject {

  /** Constructor for use by subclasses. */
  protected ForwardingObject() {}

  /**

   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <T extends @Nullable Object, K extends Enum<K>, V>

Since the naming of the properties no longer suggests they are experimental, we want to ensure users are aware if the current property stops having an effect.
Since the underlying feature is incubating, its actual behavior can still change or be removed in the minor releases.

 * JDK toolchain factory.
 * This is a <code>ToolchainFactory</code> Plexus component registered with
 * <code>jdk</code> hint.
 *
 * @since 2.0.9, renamed from <code>DefaultJavaToolchainFactory</code> in 3.2.4
 * @deprecated Use {@link org.apache.maven.api.services.ToolchainFactory} instead.
 */
@Deprecated(since = "4.0.0")
public class JavaToolchainFactory implements ToolchainFactory {

import org.apache.maven.artifact.repository.metadata.Versioning;
import org.eclipse.aether.artifact.Artifact;

/**
 * Maven remote GAV level metadata.
 *
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */
@Deprecated(since = "4.0.0")
final class RemoteSnapshotMetadata extends MavenSnapshotMetadata {
    public static final String DEFAULT_SNAPSHOT_TIMESTAMP_FORMAT = "yyyyMMdd.HHmmss";

import java.io.File;
import java.util.Properties;

/**
 * Collects settings that control building of effective settings.
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services.SettingsBuilder} instead
 */
@Deprecated(since = "4.0.0")
public class DefaultSettingsBuildingRequest implements SettingsBuildingRequest {

    private File globalSettingsFile;

    private File projectSettingsFile;

package org.apache.maven.toolchain.io;

import java.io.IOException;

/**
 * Signals a failure to parse the toolchains due to invalid syntax (e.g. non well-formed XML or unknown elements).
 *
 * @since 3.3.0
 */
@Deprecated(since = "4.0.0")
public class ToolchainsParseException extends IOException {

    /**
     * The one-based index of the line containing the error.
     */
    private final int lineNumber;

    /**

import org.eclipse.aether.util.ConfigUtils;

/**
 * Maven GA level metadata generator.
 *
 * Version metadata contains list of existing baseVersions within this GA.
 *
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */
@Deprecated(since = "4.0.0")
class VersionsMetadataGenerator implements MetadataGenerator {

    private final Map<Object, VersionsMetadata> versions;

import java.io.IOException;

/**
 * Signals a failure to parse the settings due to invalid syntax (e.g. non well-formed XML or unknown elements).
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services.xml.SettingsXmlFactory} instead
 */
@Deprecated(since = "4.0.0")
public class SettingsParseException extends IOException {

    /**
     * The one-based index of the line containing the error.
     */

import java.util.Map;

import org.apache.maven.settings.Settings;

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

    /**
     * Writes the supplied settings to the specified file. Any non-existing parent directories of the output file will