*/
  public static <K, V> Builder<K, V> builder() {
    return new Builder<>();
  }

  /**
   * Returns a new builder, expecting the specified number of entries to be added.
   *
   * <p>If {@code expectedSize} is exactly the number of entries added to the builder before {@link
   * Builder#build} is called, the builder is likely to perform better than an unsized {@link
   * #builder()} would have.
   *

  private static final long serialVersionUID = 7249069246863182397L;

  /** Version of plus for use in retryUpdate */
  @Override
  final long fn(long v, long x) {
    return v + x;
  }

  /** Creates a new adder with initial sum of zero. */
  public LongAdder() {}

  /**
   * Adds the given value.
   *
   * @param x the value to add
   */
  @Override
  public void add(long x) {
    Cell[] as;
    long b, v;

   * Nearly all declarations in this class are package-private,
   * accessed directly by subclasses.
   *
   * Table entries are of class Cell; a variant of AtomicLong padded
   * to reduce cache contention on most processors. Padding is
   * overkill for most Atomics because they are usually irregularly
   * scattered in memory and thus don't interfere much with each

 * @deprecated This exception is no longer thrown by {@code com.google.common}. Previously, it was
 *     thrown by {@link MapMaker} computing maps. When support for computing maps was removed from
 *     {@code MapMaker}, it was added to {@code CacheBuilder}, which throws {@code
 *     ExecutionException}, {@code UncheckedExecutionException}, and {@code ExecutionError}. Any

  /**
   * Notifies the listener that a removal occurred at some point in the past.
   *
   * <p>This does not always signify that the key is now absent from the cache, as it may have
   * already been re-added.
   */
  // Technically should accept RemovalNotification<? extends K, ? extends V>, but because
  // RemovalNotification is guaranteed covariant, let's make users' lives simpler.

   *     which case the input string is always returned.
   * @param padChar the character to insert at the beginning of the result until the minimum length
   *     is reached
   * @return the padded string
   */
  public static String padStart(String string, int minLength, char padChar) {
    checkNotNull(string); // eager for GWT.
    if (string.length() >= minLength) {
      return string;
    }

import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutionException;
import javax.annotation.CheckForNull;

/**
 * A semi-persistent mapping from keys to values. Cache entries are manually added using {@link
 * #get(Object, Callable)} or {@link #put(Object, Object)}, and are stored in the cache until either
 * evicted or manually invalidated. The common way to build instances is using {@link CacheBuilder}.
 *

  public enum Modifiability {
    NONE, // immutable lists
    BY_ELEMENT, // elements can change (set), but not structure
    DIRECT_ONLY, // Element can be added and removed only via direct calls, not through iterators
    ALL // Elements can be added and removed as well as modified.
  }

  /** Handles the creation of lists needed for the tests */
  public abstract static class ListExample {

    private final String name;

  public static <E> Builder<E> builder() {
    return new Builder<>();
  }

  /**
   * Returns a new builder, expecting the specified number of distinct elements to be added.
   *
   * <p>If {@code expectedSize} is exactly the number of distinct elements added to the builder
   * before {@link Builder#build} is called, the builder is likely to perform better than an unsized
   * {@link #builder()} would have.
   *

    return new EquivalenceTester<>(equivalence);
  }

  /**
   * Adds a group of objects that are supposed to be equivalent to each other and not equivalent to
   * objects in any other equivalence group added to this tester.
   */
  @CanIgnoreReturnValue
  public EquivalenceTester<T> addEquivalenceGroup(T first, T... rest) {
    addEquivalenceGroup(Lists.asList(first, rest));
    return this;
  }