r[i].Size = getEncSize(s)
				sum += r[i].Size
			}
			return ObjectInfo{
				Size:        sum,
				UserDefined: udMap(true),
				Parts:       r,
			}
		}
		// Simple useful utilities
		repeat = func(k int64, n int) []int64 {
			a := []int64{}
			for range n {
				a = append(a, k)
			}
			return a
		}
		lsum = func(s []int64) int64 {
			sum := int64(0)

 *
 * Features:
 * - Secure key storage with optional KeyStore integration
 * - Automatic key cleanup on close
 * - Thread-safe key management
 * - Key derivation utilities
 * - Memory wiping capabilities
 */
public class SecureKeyManager implements AutoCloseable {

    private static final Logger log = LoggerFactory.getLogger(SecureKeyManager.class);

 * 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.
 *   <li>If checking an <i>impossible</i> condition (which <i>cannot</i> happen unless your own

import java.util.stream.Stream;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Supplies an arbitrary "default" instance for a wide range of types, often useful in testing
 * utilities.
 *
 * <p>Covers arrays, enums and common types defined in {@code java.lang}, {@code java.lang.reflect},
 * {@code java.io}, {@code java.nio}, {@code java.math}, {@code java.util}, {@code

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import org.jspecify.annotations.Nullable;

/**
 * Utilities for treating interruptible operations as uninterruptible. In all cases, if a thread is
 * interrupted during such a call, the call continues to block until the result is available or the

import java.nio.charset.Charset;
import java.util.Arrays;
import java.util.Random;
import java.util.Set;
import org.jspecify.annotations.NullUnmarked;
import org.junit.Assert;

/**
 * Various utilities for testing {@link HashFunction}s.
 *
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 */
@NullUnmarked
final class HashTestUtils {
  private HashTestUtils() {}

import java.util.Arrays;
import java.util.Collection;
import java.util.Map.Entry;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicReference;
import org.jspecify.annotations.Nullable;

/**
 * Utilities for working with {@link Type}.
 *
 * @author Ben Yu
 */
final class Types {

  /** Class#toString without the "class " and "interface " prefixes */

import java.util.Arrays;
import java.util.Collection;
import java.util.Map.Entry;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicReference;
import org.jspecify.annotations.Nullable;

/**
 * Utilities for working with {@link Type}.
 *
 * @author Ben Yu
 */
final class Types {

  /** Class#toString without the "class " and "interface " prefixes */

 * either {@link Boolean} or {@link Arrays}.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/PrimitivesExplained">primitive utilities</a>.
 *
 * @author Kevin Bourrillion
 * @since 1.0
 */
@GwtCompatible
public final class Booleans {
  private Booleans() {}

  /** Comparators for {@code Boolean} values. */

 *   <li>Running tasks <i>cannot</i> be interrupted. (Note that {@code newSequentialExecutor} does
 *       not return {@code Future} objects, so it doesn't support interruption directly, either.
 *       However, utilities that <i>use</i> that executor have the ability to interrupt tasks
 *       running on it. This class, by contrast, does not expose an {@code Executor} API.)
 * </ul>
 *