How to use

hashCode

method

in

java.lang.Object

/**
 * Returns the hashCode of a non-null object or zero for a null object.
 * @param o the object to get the hashCode for.
 * @return the hashCode
 */
public static int hashCode(Object o) {
  return o != null ? o.hashCode() : 0;
}

@Override
public int hashCode() {
  Object o = value;
  return o != null ? o.hashCode() : 0;
}

/** An implementation of {@link List#hashCode()}. */
static int hashCodeImpl(List<?> list) {
 // TODO(lowasser): worth optimizing for RandomAccess?
 int hashCode = 1;
 for (Object o : list) {
  hashCode = 31 * hashCode + (o == null ? 0 : o.hashCode());
  hashCode = ~~hashCode;
  // needed to deal with GWT integer overflow
 }
 return hashCode;
}

/** An implementation for {@link Set#hashCode()}. */
static int hashCodeImpl(Set<?> s) {
 int hashCode = 0;
 for (Object o : s) {
  hashCode += o != null ? o.hashCode() : 0;
  hashCode = ~~hashCode;
  // Needed to deal with unusual integer overflow in GWT.
 }
 return hashCode;
}

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

 @Override
 public int hashCode() {
  return SequentialFunnel.class.hashCode() ^ elementFunnel.hashCode();
 }
}

@Override public int hashCode() {
 return Arrays.hashCode(typeArguments)
   ^ rawType.hashCode()
   ^ (ownerType != null ? ownerType.hashCode() : 0);
}

@Override
public int hashCode() {
 return (ownerType == null ? 0 : ownerType.hashCode())
   ^ argumentsList.hashCode()
   ^ rawType.hashCode();
}

@Override
public int hashCode() {
 int hashCode = 1;
 int n = size();
 for (int i = 0; i < n; i++) {
  hashCode = 31 * hashCode + get(i).hashCode();
  hashCode = ~~hashCode;
  // needed to deal with GWT integer overflow
 }
 return hashCode;
}

@Override
public int hashCode() {
   int h = value != null ? value.hashCode() : 0;
   h = h * 31 + (int)((time >>> 31) ^ time);
   h = h * 31 + unit.hashCode();
   return h;
}

@Override public int hashCode() {
 int result = 17;
 result = 31 * result + tlsVersion.hashCode();
 result = 31 * result + cipherSuite.hashCode();
 result = 31 * result + peerCertificates.hashCode();
 result = 31 * result + localCertificates.hashCode();
 return result;
}

@Override
public int hashCode() {
 K k = getKey();
 V v = getValue();
 return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
}

@Override
public int hashCode() {
 K k = getKey();
 V v = getValue();
 return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
}

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

 @Override
 public Integer apply(Object o) {
  return (o == null) ? 0 : o.hashCode();
 }
}

public void testHashCode() {
 int expectedHashCode = 1;
 for (E element : getOrderedElements()) {
  expectedHashCode = 31 * expectedHashCode + ((element == null) ? 0 : element.hashCode());
 }
 assertEquals(
   "A List's hashCode() should be computed from those of its elements.",
   expectedHashCode,
   getList().hashCode());
}

public void testHashCode() {
 int expectedHashCode = 0;
 for (E element : getSampleElements()) {
  expectedHashCode += ((element == null) ? 0 : element.hashCode());
 }
 assertEquals(
   "A Set's hashCode() should be the sum of those of its elements.",
   expectedHashCode,
   getSet().hashCode());
}

private static void assertEqualWildcardType(WildcardType expected, WildcardType actual) {
 assertEquals(expected.toString(), actual.toString());
 assertEquals(actual.toString(), expected.hashCode(), actual.hashCode());
 assertThat(actual.getLowerBounds())
   .asList()
   .containsExactlyElementsIn(asList(expected.getLowerBounds()))
   .inOrder();
 assertThat(actual.getUpperBounds())
   .asList()
   .containsExactlyElementsIn(asList(expected.getUpperBounds()))
   .inOrder();
}

 @CollectionSize.Require(ONE)
 public void testHashCode_size1() {
  assertEquals("multiset has incorrect hash code", 1 ^ e0().hashCode(), getMultiset().hashCode());
 }
}

  @Test
  public void errorNotificationCompare() {
    TestException ex = new TestException();
    Object n1 = NotificationLite.error(ex);

    assertEquals(ex.hashCode(), n1.hashCode());

    assertFalse(n1.equals(NotificationLite.complete()));
  }
}