# Advanced User Guide

## Additional Features

The main [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} should be enough to give you a tour through all the main features of **FastAPI**.

In the next sections you will see other options, configurations, and additional features.

/// tip

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

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

///

    @Serial
    private static final long serialVersionUID = 4714858598345418083L;

    private final List<BuilderProblem> problems;

    /**
     * @param message the message to give
     * @param e the {@link Exception}
     */
    public SettingsBuilderException(String message, Exception e) {
        super(message, e);
        this.problems = List.of();
    }

    @Serial
    private static final long serialVersionUID = 7899871809665729349L;

    private final List<BuilderProblem> problems;

    /**
     * @param message the message to give
     * @param e the {@link Exception}
     */
    public ToolchainsBuilderException(String message, Exception e) {
        super(message, e);
        this.problems = List.of();
    }

### Other (Cleanup or Flake)

                                        "value": {
                                            "name": "Baz",
                                            "price": "thirty five point four",
                                        },
                                    },
                                },
                            }
                        },

  private static final Integer I0 = -45;
  private static final Integer I1 = -1;
  private static final Integer I2 = 3;
  private static final String S0 = "3";
  private static final String S1 = "Ninety five";
  private static final String S2 = "44 one million";
  private static final String S3 = "Lowly laundry lefties";
  private static final String S4 = "89273487U#*&#";
  private static final Double D0 = 9.234d;

    return new SampleElements<>(
        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public final BiMap<String, String> create(Object... entries) {
    @SuppressWarnings("unchecked")
    Entry<String, String>[] array = (Entry<String, String>[]) new Entry<?, ?>[entries.length];

    return new SampleElements<>(
        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public final BiMap<String, String> create(Object... entries) {
    @SuppressWarnings("unchecked")
    Entry<String, String>[] array = (Entry<String, String>[]) new Entry<?, ?>[entries.length];

    return new SampleElements<>(
        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public Map<String, String> create(Object... entries) {
    @SuppressWarnings("unchecked")
    Entry<String, String>[] array = (Entry<String, String>[]) new Entry<?, ?>[entries.length];

}


class IntegrationTestFixtureVisitor : AbstractAstVisitor() {

    /**
     * Determines if the class is an integration test. It's a bit weak, but we cannot
     * rely on the class node analysis since it doesn't give the right superclass because
     * resolution is not complete when this visitor is executed.
     */
    private
    fun isIntegrationTest(current: ClassNode) = current.name.endsWith("Test")