* Optional.orElseGet}, except when {@code supplier} returns {@code null}. In this case this
   * method throws an exception, whereas the Java 8+ method returns the {@code null} to the caller.
   *
   * @throws NullPointerException if this optional's value is absent and the supplier returns {@code
   *     null}
   */
  public abstract T or(Supplier<? extends T> supplier);

  /**

 * which approach to use, <b>don't worry</b> too much about it; just pick something that seems
 * reasonable and it will be fine.
 *
 * <ul>
 *   <li>If checking whether the <i>caller</i> has violated your method or constructor's contract
 *       (such as by passing an invalid argument), use the utilities of the {@link Preconditions}
 *       class instead.

    }
    return wrapCollection(key, collection);
  }

  /**
   * Generates a decorated collection that remains consistent with the values in the multimap for
   * the provided key. Changes to the multimap may alter the returned collection, and vice versa.
   */
  Collection<V> wrapCollection(@ParametricNullness K key, Collection<V> collection) {
    return new WrappedCollection(key, collection, null);
  }

      thrownUnsafeFailure = unsafeFailure;
      // catch absolutely everything and fall through to our 'SafeAtomicHelper'
      // The access control checks that ARFU does means the caller class has to be AbstractFuture
      // instead of SafeAtomicHelper, so we annoyingly define these here
      try {
        helper =
            new SafeAtomicHelper(

    volatile int count;

    /** The weight of the live elements in this segment's region. */
    @GuardedBy("this")
    long totalWeight;

    /**
     * Number of updates that alter the size of the table. This is used during bulk-read methods to
     * make sure they see a consistent snapshot: If modCounts change during a traversal of segments

            visitor.onText(value);
        }

        // end of tag marker
        if (scanner.lookingAt('}')) {
            visitor.onEndJavadocTag(tagName);
            scanner.next();
        }
    }

    private void parseStartElement(TokenVisitor visitor) {
        // start element marker
        scanner.next();
        boolean isEnd = false;
        if (scanner.lookingAt('/')) {

 *
 * <p>{@code CharSink} provides two kinds of methods:
 *
 * <ul>
 *   <li><b>Methods that return a writer:</b> These methods should return a <i>new</i>, independent
 *       instance each time they are called. The caller is responsible for ensuring that the
 *       returned writer is closed.
 *   <li><b>Convenience methods:</b> These are implementations of common operations that are

 * under the License.
 */
package org.apache.maven.api;

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.ThreadSafe;

/**
 * Marker interface for all services provided by the {@link Session}.
 * <p>
 * Services can be retrieved from the session using the
 * {@link Session#getService(Class)} method.
 *
 * @since 4.0.0
 * @see Session#getService(Class)

public interface RepositorySystemSessionFactory {
    /**
     * Creates "ready to use" session builder instance. The factory does not set up one thing: the
     * {@link org.eclipse.aether.repository.WorkspaceReader}s, that is caller duty to figure out. Workspace readers
     * should be set up as very last thing before using resolver session, that is built by invoking
     * {@link SessionBuilder#build()} method.
     *

        // ignore
      }
    }
  }

  /**
   * Cleans up the given reference and any other references already in the queue. Catches and logs
   * all throwables.
   *
   * @return true if the caller should continue to wait for more references to be added to the
   *     queue, false if the associated FinalizableReferenceQueue is no longer referenced.
   */
  private boolean cleanUp(Reference<?> firstReference) {