*
 * @author Charles Fry
 * @since 10.0
 */
@GwtIncompatible
public abstract class ForwardingCache<K, V> extends ForwardingObject implements Cache<K, V> {

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

  @Override
  protected abstract Cache<K, V> delegate();

  /**
   * @since 11.0
   */
  @Override
  public @Nullable V getIfPresent(Object key) {

 */

/**
 * An abstract class for NTLM authentication in SMB1 protocol.
 * Provides a callback mechanism for retrieving user credentials when authentication is required.
 */
public abstract class NtlmAuthenticator {

    /**
     * Default constructor.
     */
    protected NtlmAuthenticator() {
        // Protected constructor for abstract class
    }

    private static NtlmAuthenticator auth;

import org.dbflute.util.DfCollectionUtil;
import org.opensearch.action.delete.DeleteRequestBuilder;
import org.opensearch.action.index.IndexRequestBuilder;

/**
 * @author ESFlute (using FreeGen)
 */
public abstract class EsAbstractEntity implements Entity, Serializable, Cloneable {

    // ===================================================================================

import org.gradle.internal.os.OperatingSystem
import javax.inject.Inject


abstract class BuildEnvironmentService : BuildService<BuildEnvironmentService.Parameters> {

    interface Parameters : BuildServiceParameters {
        val rootProjectDir: DirectoryProperty
        val rootProjectBuildDir: DirectoryProperty
    }

    @get:Inject
    abstract val providers: ProviderFactory

    val gitCommitId = git("rev-parse", "HEAD")

/**
 * Abstract {@link Hasher} that handles converting primitives to bytes using a scratch {@code
 * ByteBuffer} and streams all bytes to a sink to compute the hash.
 *
 * @author Colin Decker
 */
abstract class AbstractByteHasher extends AbstractHasher {
  private @Nullable ByteBuffer scratch;

  /** Updates this hasher with the given byte. */
  protected abstract void update(byte b);

import org.apache.maven.api.cli.mvnup.UpgradeOptions;
import org.apache.maven.cling.invoker.mvnup.UpgradeContext;

import static eu.maveniverse.domtrip.maven.MavenPomElements.Elements.PARENT;

/**
 * Abstract base class for upgrade strategies that provides common functionality
 * and reduces code duplication across strategy implementations.
 *
 * <p>Strategies work with domtrip Documents for perfect formatting preservation.

 *     source-compatible</a> since 9.0)
 */
@GwtCompatible
public abstract class Ticker {
  /** Constructor for use by subclasses. */
  protected Ticker() {}

  /** Returns the number of nanoseconds elapsed since this ticker's fixed point of reference. */
  public abstract long read();

  /**
   * A ticker that reads the current time using {@link System#nanoTime}.
   *
   * @since 10.0

  // so that we can then report them during tearDown.

  abstract class CheckedRunnable implements Runnable {
    abstract void realRun() throws Throwable;

    @Override
    public final void run() {
      try {
        realRun();
      } catch (Throwable t) {
        threadUnexpectedException(t);
      }
    }
  }

  abstract class CheckedCallable<T> implements Callable<T> {

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.jspecify.annotations.Nullable;

/**
 * An abstract {@code ExecutorService} that allows subclasses to {@linkplain #wrapTask(Callable)
 * wrap} tasks before they are submitted to the underlying executor.
 *
 * <p>Note that task wrapping may occur even if the task is never executed.

package com.google.common.util.concurrent;

import static com.google.common.collect.Sets.newHashSet;

import java.util.Set;
import org.jspecify.annotations.Nullable;

/** Emulation of AggregateFutureState. */
abstract class AggregateFutureState<OutputT extends @Nullable Object>
    extends AbstractFuture.TrustedFuture<OutputT> {
  // Lazily initialized the first time we see an exception; not released until all the input futures