}

    /**
     * Verify that root causes are stored and returned correctly.
     */
    @Test
    @DisplayName("Root cause propagation")
    void testRootCausePropagation() {
        Throwable root = mock(Throwable.class);
        SmbException ex = new SmbException(0, root);
        assertSame(root, ex.getRootCause());
    }

    /**

    TestSubtype spec = method.getAnnotation(TestSubtype.class);
    assertWithMessage("%s is subtype of %s", paramType, returnType)
        .that(TypeToken.of(paramType).isSubtypeOf(returnType))
        .isTrue();
    assertWithMessage("%s is supertype of %s", returnType, paramType)
        .that(TypeToken.of(returnType).isSupertypeOf(paramType))
        .isTrue();
    if (!spec.suppressGetSubtype()) {

      }
    }
  }

  /** Tests that if specify '%' as safe the result is an idempotent escaper. */
  public void testCustomEscaper_withpercent() {
    UnicodeEscaper e = new PercentEscaper("%", false);
    assertThat(e.escape("foo|bar")).isEqualTo("foo%7Cbar");
    assertThat(e.escape("foo%7Cbar")).isEqualTo("foo%7Cbar"); // idempotent
  }

It just extends OAuth2 specifying some things that are relatively ambiguous in OAuth2, to try to make it more interoperable.

For example, Google login uses OpenID Connect (which underneath uses OAuth2).

But Facebook login doesn't support OpenID Connect. It has its own flavor of OAuth2.

### OpenID (not "OpenID Connect") { #openid-not-openid-connect }

* For `PUT` requests to `/items/{item_id}`, read the body as JSON:
    * Check that it has a required attribute `name` that should be a `str`.
    * Check that it has a required attribute `price` that has to be a `float`.
    * Check that it has an optional attribute `is_offer`, that should be a `bool`, if present.
    * All this would also work for deeply nested JSON objects.

 * {@link #enqueue} and {@link #dispatch} are 2 different methods. It is expected that the decision
 * to run a particular event is made during the state change, but the decision to actually invoke
 * the listeners can be delayed slightly so that locks can be dropped. Also, because {@link
 * #dispatch} is expected to be called concurrently, it is idempotent.
 */
@J2ktIncompatible

        assertTrue(exception instanceof Exception);
        assertTrue(exception instanceof Throwable);
    }

    @Test
    public void test_stackTrace() {
        // Test that stack trace is populated
        UnsupportedSearchException exception = new UnsupportedSearchException("test message");

        assertNotNull(exception.getStackTrace());

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.concurrent.atomic.AtomicLong;

/**
 * One or more variables that together maintain an initially zero {@code long} sum. When updates
 * (method {@link #add}) are contended across threads, the set of variables may grow dynamically to

    // Later attempts to set the future should return false.
    assertFalse(future.set(23));
    assertFalse(future.setException(new Exception("bar")));
    assertFalse(future.setFuture(SettableFuture.create()));
    // Check that the future has been set properly.
    assertTrue(future.isDone());
    assertFalse(future.isCancelled());
    assertEquals(42, (int) future.get());
  }

  public void testSetException() throws Exception {

There is also an **Advanced User Guide** that you can read later after this **Tutorial - User guide**.

The **Advanced User Guide** builds on this one, uses the same concepts, and teaches you some extra features.

But you should first read the **Tutorial - User Guide** (what you are reading right now).