RESTRICTS_KEYS,
  RESTRICTS_VALUES,
  SUPPORTS_PUT,
  SUPPORTS_REMOVE,
  FAILS_FAST_ON_CONCURRENT_MODIFICATION,
  /**
   * Indicates that the constructor or factory method of a map, usually an immutable map, throws an
   * {@link IllegalArgumentException} when presented with duplicate keys instead of discarding all
   * but one.
   */
  REJECTS_DUPLICATES_AT_CREATION,

  GENERAL_PURPOSE(SUPPORTS_PUT, SUPPORTS_REMOVE);

    <artifactId>maven-api</artifactId>
    <version>4.1.0-SNAPSHOT</version>
  </parent>

  <artifactId>maven-api-toolchain</artifactId>

  <name>Maven 4 API :: Toolchain</name>
  <description>Maven 4 API - Immutable Toolchain model.</description>

  <dependencies>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-annotations</artifactId>
    </dependency>
    <dependency>

    <artifactId>maven</artifactId>
    <version>4.1.0-SNAPSHOT</version>
  </parent>

  <artifactId>maven-api</artifactId>
  <packaging>pom</packaging>
  <name>Maven 4 API</name>
  <description>A new immutable API for Maven 4 to better manage what plugins and extensions can influence.</description>

  <modules>
    <module>maven-api-annotations</module>
    <module>maven-api-di</module>
    <module>maven-api-xml</module>

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.api;

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Immutable;
import org.apache.maven.api.annotations.Nonnull;

/**
 * A Maven artifact is a file, typically a JAR, that is produced and used by Maven projects.

    this.allowsSelfLoops = allowsSelfLoops;
  }

  @Override
  public Graph<Integer> createGraph() {
    graphBuilder = GraphBuilder.directed().allowsSelfLoops(allowsSelfLoops).immutable();
    return graphBuilder.build();
  }

  @Override
  final void addNode(Integer n) {
    graphBuilder.addNode(n);
    graph = graphBuilder.build();
  }

  @Override

    this.allowsSelfLoops = allowsSelfLoops;
  }

  @Override
  public Graph<Integer> createGraph() {
    graphBuilder = GraphBuilder.undirected().allowsSelfLoops(allowsSelfLoops).immutable();
    return graphBuilder.build();
  }

  @Override
  final void addNode(Integer n) {
    graphBuilder.addNode(n);
    graph = graphBuilder.build();
  }

  @Override

   * {@code Optional.orElse(null)}.
   */
  public abstract @Nullable T orNull();

  /**
   * Returns an immutable singleton {@link Set} whose only element is the contained instance if it
   * is present; an empty immutable {@link Set} otherwise.
   *
   * <p><b>Comparison to {@code java.util.Optional}:</b> this method has no equivalent in Java 8's

import java.io.FilenameFilter;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

/**
 * File name filter that only accepts files matching a regular expression. This class is thread-safe
 * and immutable.
 *
 * @author Apple Chow
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class PatternFilenameFilter implements FilenameFilter {

  private final Pattern pattern;

  /**

   * @return an immutable set containing those elements, minus duplicates
   */
  public static <E extends Enum<E>> ImmutableSet<E> immutableEnumSet(
      E anElement, E... otherElements) {
    return ImmutableEnumSet.asImmutable(EnumSet.of(anElement, otherElements));
  }

  /**
   * Returns an immutable set instance containing the given enum elements. Internally, the returned

import java.util.List;
import java.util.Optional;
import java.util.function.Predicate;
import java.util.stream.Stream;

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Immutable;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.annotations.Provider;

/**