public void normalNullable(String first, @Nullable Integer second) {
      reactToNullParameters(first, second);
    }

    /** Two-arg method with the first param Nullable. */
    public void nullableNormal(@Nullable String first, Integer second) {
      reactToNullParameters(first, second);
    }

    /** Two-arg method with the both params Nullable. */

   *
   * <p><b>Note:</b> if {@code first} is represented as an {@link Optional}, this can be
   * accomplished with {@link Optional#or(Object) first.or(second)}. That approach also allows for
   * lazy evaluation of the fallback instance, using {@link Optional#or(Supplier)
   * first.or(supplier)}.
   *
   * <p><b>Java 9 users:</b> use {@code java.util.Objects.requireNonNullElse(first, second)}
   * instead.
   *

        // Then
        assertTrue(result > 0);
        assertEquals((byte) 0x04, dst[0]); // First buffer format byte

        // Find the second buffer format byte
        int secondBufferFormatIndex = oldFileName.length() + 2; // 1 for first 0x04, 1 for null terminator
        assertEquals((byte) 0x04, dst[secondBufferFormatIndex]);
    }

    /**

   * as a false predicate is found.
   *
   * <p><b>Discouraged:</b> Prefer using {@code first.and(second)}.
   */
  public static <T extends @Nullable Object> Predicate<T> and(
      Predicate<? super T> first, Predicate<? super T> second) {
    return new AndPredicate<>(Predicates.<T>asList(checkNotNull(first), checkNotNull(second)));
  }

  /**

        // Verify little-endian encoding
        assertEquals((byte) 0xA1, encoded[0], "First byte of first character");
        assertEquals((byte) 0x00, encoded[1], "Second byte of first character");
        assertEquals((byte) 0xA2, encoded[2], "First byte of second character");
        assertEquals((byte) 0x00, encoded[3], "Second byte of second character");
    }

    @Test

    }
  }

  /**
   * Constructs an {@code ImmutableSortedSet} from the first {@code n} elements of {@code contents}.
   * If {@code k} is the size of the returned {@code ImmutableSortedSet}, then the sorted unique
   * elements are in the first {@code k} positions of {@code contents}, and {@code contents[i] ==
   * null} for {@code k <= i < n}.
   *

   * will remember the first duplicate key we encountered. All later calls to buildOrThrow() can
   * mention that key with its values. Further duplicates might be added in the meantime but since
   * builders only ever accumulate entries it will always be valid to throw from buildOrThrow() with
   * the first duplicate.
   */

        String result = StringUtil.join(null, "first", "second", "third");
        assertEquals("firstnullsecondnullthird", result);
    }

    @Test
    @DisplayName("Should handle null elements in array")
    void testJoinWithNullElements() {
        String result = StringUtil.join(",", "first", null, "third");
        assertEquals("first,null,third", result);
    }

    @Test

        // List with first element NOT being Entity
        List<Object> mixedList = new ArrayList<>();
        mixedList.add("string first");
        mixedList.add(entity);

        RenderDataUtil.register(data, "mixed", mixedList);

        Object result = data.getDataMap().get("mixed");
        assertEquals(mixedList, result); // Should be registered as-is since first element is not Entity
    }

/// tip

The next sections are **not necessarily "advanced"**.

And it's possible that for your use case, the solution is in one of them.

///

## Read the Tutorial first { #read-the-tutorial-first }

The next sections assume you already read the main [Tutorial - User Guide: Security](../../tutorial/security/index.md){.internal-link target=_blank}.