public static Equivalence<Object> identity() {
    return Identity.INSTANCE;
  }

  static final class Equals extends Equivalence<Object> implements Serializable {

    static final Equals INSTANCE = new Equals();

    @Override
    protected boolean doEquivalent(Object a, Object b) {
      return a.equals(b);
    }

    @Override
    protected int doHash(Object o) {
      return o.hashCode();
    }

  public static Equivalence<Object> identity() {
    return Identity.INSTANCE;
  }

  static final class Equals extends Equivalence<Object> implements Serializable {

    static final Equals INSTANCE = new Equals();

    @Override
    protected boolean doEquivalent(Object a, Object b) {
      return a.equals(b);
    }

    @Override
    protected int doHash(Object o) {
      return o.hashCode();
    }

      return p.apply(f.apply(a));
    }

    @Override
    public boolean equals(@CheckForNull Object obj) {
      if (obj instanceof CompositionPredicate) {
        CompositionPredicate<?, ?> that = (CompositionPredicate<?, ?>) obj;
        return f.equals(that.f) && p.equals(that.p);
      }
      return false;
    }

    @Override
    public int hashCode() {

    return delegate().setValue(value);
  }

  @Override
  public boolean equals(@CheckForNull Object object) {
    return delegate().equals(object);
  }

  @Override
  public int hashCode() {
    return delegate().hashCode();
  }

  /**
   * A sensible definition of {@link #equals(Object)} in terms of {@link #getKey()} and {@link

    // Explicitly call `equals`; `assertEquals` might return fast
    assertTrue(foo1.equals(foo1));
    assertEquals(control("foo", 1), foo1);
    assertEquals(control("bar", 2), entry("bar", 2));
    assertFalse(control("foo", 1).equals(entry("foo", 2)));
    assertFalse(foo1.equals(control("bar", 1)));
    assertFalse(foo1.equals(new Object()));
    assertFalse(foo1.equals(null));
  }

  public void testEqualsNull() {

    }

    public void test_equals1() {
        final KuromojiItem kuromojiItem1 = new KuromojiItem(1, "t1", "s1", "r1", "p1");

        assertTrue(kuromojiItem1.equals(kuromojiItem1));
        assertTrue(kuromojiItem1.equals(new KuromojiItem(1, "t1", "s1", "r1", "p1")));
        assertTrue(kuromojiItem1.equals(new KuromojiItem(2, "t1", "s1", "r1", "p1")));
        assertFalse(kuromojiItem1.equals(new KuromojiItem(1, "T1", "s1", "r1", "p1")));

        final SynonymItem synonymItem1 = new SynonymItem(1, new String[] { "a" }, new String[] { "b" });

        assertTrue(synonymItem1.equals(synonymItem1));
        assertTrue(synonymItem1.equals(new SynonymItem(1, new String[] { "a" }, new String[] { "b" })));
        assertFalse(synonymItem1.equals(new SynonymItem(2, new String[] { "a" }, new String[] { "B", })));

    }

    @Override
    public boolean equals(@CheckForNull Object other) {
      if (!(other instanceof ParameterizedType)) {
        return false;
      }
      ParameterizedType that = (ParameterizedType) other;
      return getRawType().equals(that.getRawType())
          && Objects.equal(getOwnerType(), that.getOwnerType())
          && Arrays.equals(getActualTypeArguments(), that.getActualTypeArguments());
    }

        .addEquivalenceGroup(ImmutableList.of("a", "b"), ImmutableList.of("a", "b"))
        .test();
  }

  public void testPairwiseEquivalent_equals() {
    new EqualsTester()
        .addEqualityGroup(Equivalence.equals().pairwise(), Equivalence.equals().pairwise())
        .addEqualityGroup(Equivalence.identity().pairwise())
        .testEquals();
  }

import junit.framework.AssertionFailedError;
import org.checkerframework.checker.nullness.qual.Nullable;

@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class Helpers {
  // Clone of Objects.equal
  static boolean equal(@Nullable Object a, @Nullable Object b) {
    return a == b || (a != null && a.equals(b));
  }

  // Clone of Lists.newArrayList