/**
 * Provides similar behavior to {@link String#intern} for any immutable type. Common implementations
 * are available from the {@link Interners} class.
 *
 * <p>Note that {@code String.intern()} has some well-known performance limitations, and should
 * generally be avoided. Prefer {@link Interners#newWeakInterner} or another {@code Interner}
 * implementation even for {@code String} interning.
 *

/**
 * Provides similar behavior to {@link String#intern} for any immutable type. Common implementations
 * are available from the {@link Interners} class.
 *
 * <p>Note that {@code String.intern()} has some well-known performance limitations, and should
 * generally be avoided. Prefer {@link Interners#newWeakInterner} or another {@code Interner}
 * implementation even for {@code String} interning.
 *

    assertEquals(Strength.WEAK, internerImpl.map.keyStrength());
    assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel);
  }


  public void testWeak_afterGC() throws InterruptedException {
    Integer canonical = new Integer(5);
    Integer not = new Integer(5);

    Interner<Integer> pool = Interners.newWeakInterner();
    assertSame(canonical, pool.intern(canonical));

  /**
   * Returns a function that delegates to the {@link Interner#intern} method of the given interner.
   *
   * @since 8.0
   */
  public static <E> Function<E, E> asFunction(Interner<E> interner) {
    return new InternerFunction<>(checkNotNull(interner));
  }

  private static class InternerFunction<E> implements Function<E, E> {

    private final Interner<E> interner;

    public InternerFunction(Interner<E> interner) {

  /**
   * Returns a function that delegates to the {@link Interner#intern} method of the given interner.
   *
   * @since 8.0
   */
  public static <E> Function<E, E> asFunction(Interner<E> interner) {
    return new InternerFunction<>(checkNotNull(interner));
  }

  private static class InternerFunction<E> implements Function<E, E> {

    private final Interner<E> interner;

    public InternerFunction(Interner<E> interner) {

import com.google.caliper.Benchmark;

/**
 * Benchmarking interners.
 *
 * @author Dimitris Andreou
 */
public class InternersBenchmark {
  @Benchmark
  int weakInterner(int reps) {
    Interner<String> interner = Interners.newWeakInterner();
    for (int i = 0; i < reps; i++) {
      String unused = interner.intern(Double.toHexString(Math.random()));
    }
    return reps;
  }

  @Benchmark

    assertEquals(Strength.WEAK, internerImpl.map.keyStrength());
    assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel);
  }


  public void testWeak_afterGC() throws InterruptedException {
    Integer canonical = new Integer(5);
    Integer not = new Integer(5);

    Interner<Integer> pool = Interners.newWeakInterner();
    assertSame(canonical, pool.intern(canonical));

import com.google.caliper.Benchmark;

/**
 * Benchmarking interners.
 *
 * @author Dimitris Andreou
 */
public class InternersBenchmark {
  @Benchmark
  int weakInterner(int reps) {
    Interner<String> interner = Interners.newWeakInterner();
    for (int i = 0; i < reps; i++) {
      String unused = interner.intern(Double.toHexString(Math.random()));
    }
    return reps;
  }

  @Benchmark

    WeakInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {
        Interner<E> interner = Interners.newWeakInterner();
        for (E e : contents) {
          E unused = interner.intern(e);
        }
        return interner;
      }
    },
    StrongInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {

    WeakInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {
        Interner<E> interner = Interners.newWeakInterner();
        for (E e : contents) {
          E unused = interner.intern(e);
        }
        return interner;
      }
    },
    StrongInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {