String supportEmail = (String) defaultSettings.get("onelogin.saml2.contacts.support.email_address");

        // Both should have exactly one @ character
        assertEquals("Email should have exactly one @ character", 1, techEmail.split("@", -1).length - 1);
        assertEquals("Email should have exactly one @ character", 1, supportEmail.split("@", -1).length - 1);

        // Specific value check

#### Password hashing { #password-hashing }

"Hashing" means: converting some content (a password in this case) into a sequence of bytes (just a string) that looks like gibberish.

Whenever you pass exactly the same content (exactly the same password) you get exactly the same gibberish.

But you cannot convert from the gibberish back to the password.

##### Why use password hashing { #why-use-password-hashing }

   * @throws IllegalArgumentException if the stream consists of two or more elements.
   * @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be
   *     {@code null}) and returns {@code Optional.empty()} if it has none.
   */
  @SuppressWarnings("unchecked")
  public static <T> Collector<T, ?, Optional<T>> toOptional() {

   * @throws IllegalArgumentException if the stream consists of two or more elements.
   * @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be
   *     {@code null}) and returns {@code Optional.empty()} if it has none.
   */
  @SuppressWarnings("unchecked")
  public static <T> Collector<T, ?, Optional<T>> toOptional() {

 *
 * @author Louis Wasserman
 */
public class OutsideEventBusTest extends TestCase {

  /*
   * If you do this test from common.eventbus.EventBusTest, it doesn't actually test the behavior.
   * That is, even if exactly the same method works from inside the common.eventbus package tests,
   * it can fail here.
   */
  public void testAnonymous() {
    AtomicReference<String> holder = new AtomicReference<>();

        method.setAccessible(true);
        final List<String> indices = (List<String>) method.invoke(suggester, aliasName);

        assertNotNull("Indices list should not be null", indices);
        assertEquals("Should find exactly one index", 1, indices.size());
        assertEquals("Should return correct index name", indexName, indices.get(0));

        // Cleanup
        client.admin().indices().prepareDelete(indexName).execute().actionGet();

 *
 * @author Louis Wasserman
 */
public class OutsideEventBusTest extends TestCase {

  /*
   * If you do this test from common.eventbus.EventBusTest, it doesn't actually test the behavior.
   * That is, even if exactly the same method works from inside the common.eventbus package tests,
   * it can fail here.
   */
  public void testAnonymous() {
    AtomicReference<String> holder = new AtomicReference<>();

            System.setProperty(Constants.FESS_SEARCH_ENGINE_HTTP_ADDRESS, testAddress);
            String result = SystemUtil.getSearchEngineHttpAddress();
            assertEquals(testAddress, result); // Should return exactly what's in the property
        } finally {
            // Restore original value
            if (originalValue != null) {
                System.setProperty(Constants.FESS_SEARCH_ENGINE_HTTP_ADDRESS, originalValue);

        "network interceptor ${interceptors[index - 1]} must retain the same host and port"
      }
      check(calls == 1) {
        "network interceptor ${interceptors[index - 1]} must call proceed() exactly once"
      }
    }

    // Call the next interceptor in the chain.
    val next = copy(index = index + 1, request = request)
    val interceptor = interceptors[index]

    @Suppress("USELESS_ELVIS")

For example, in one of the ways the OAuth2 specification can be used (called "password flow") it is required to send a `username` and `password` as form fields.

The <dfn title="specification">spec</dfn> requires the fields to be exactly named `username` and `password`, and to be sent as form fields, not JSON.