*       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

   * such as:
   *
   * - Make checkOpen return the non-null `seq`. Then callers can assign that to a local variable or
   *   even back to `this.seq`. However, that may suggest that we're defending against concurrent
   *   mutation, which is not an actual risk because we use `synchronized`.
   * - Make `remaining` require a non-null `seq` argument. But this is a bit weird because the

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

func (b *Reader) ReadBytes(delim byte) ([]byte, error) {
	full, frag, n, err := b.collectFragments(delim)
	// Allocate new buffer to hold the full pieces and the fragment.
	buf := make([]byte, n)
	n = 0
	// Copy full pieces and fragment in.
	for i := range full {
		n += copy(buf[n:], full[i])
	}
	copy(buf[n:], frag)
	return buf, err
}

        final Integer threadCheckCount = (Integer) objs[2];
        if (logger.isDebugEnabled()) {
            if (urlQueue != null && urlQueue.getUrl() != null) {
                logger.debug("{} is not a target url. ({})", urlQueue.getUrl(), threadCheckCount);
            } else {
                logger.debug("The url is null. ({})", threadCheckCount);
            }
        }
    }

    @Test
    void testMirrorLayoutConsideredForMatching() {
        ArtifactRepository repo = getRepo("a");

        Mirror mirrorA = newMirror("a", "a", null, "http://a");
        Mirror mirrorB = newMirror("b", "a", "p2", "http://b");

        Mirror mirrorC = newMirror("c", "*", null, "http://c");
        Mirror mirrorD = newMirror("d", "*", "p2", "http://d");

                    return groovyShell.evaluate(template);
                } catch (final JobProcessingException e) {
                    throw e;
                } catch (final Exception e) {
                    return null;
                } finally {
                    final GroovyClassLoader loader = groovyShell.getClassLoader();
                    loader.clearCache();
                }
            }

            @Override

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image02.png">
</div>

Isso significa que ele **sempre terá um valor**, só que às vezes o valor pode ser `None` (ou `null` em termos de JSON).