@ElementTypesAreNonnullByDefault
public final class Callables {
  private Callables() {}

  /** Creates a {@code Callable} which immediately returns a preset value each time it is called. */
  public static <T extends @Nullable Object> Callable<T> returning(@ParametricNullness T value) {
    return () -> value;
  }

  /**
   * Creates an {@link AsyncCallable} from a {@link Callable}.
   *

   | * type: the type of tool. An often used value is 'jdk'. Toolchains-aware
   |   plugins should document which type you must use.
   |
   | * provides: A list of key/value-pairs.
   |   Based on the toolchain-configuration in the pom.xml Maven will search for
   |   matching <provides/> configuration. You can decide for yourself which key-value

    /**
     * Class definition
     */
    private final boolean errors;

    private final T value;

    private final Iterable<? extends ModelProblem> problems;

    private Result(boolean errors, T model, Iterable<? extends ModelProblem> problems) {
        this.errors = errors;
        this.value = model;
        this.problems = problems;
    }

    public Iterable<? extends ModelProblem> getProblems() {

)

// DefaultKVS - default config for Authz plugin config
var (
	DefaultKVS = config.KVS{
		config.KV{
			Key:   URL,
			Value: "",
		},
		config.KV{
			Key:   AuthToken,
			Value: "",
		},
		config.KV{
			Key:   EnableHTTP2,
			Value: "off",
		},
	}
)

// Args for general purpose policy engine configuration.
type Args struct {
	URL         *xnet.URL             `json:"url"`

		// Do not enable if opaArgs was empty.
		return
	}
	s[config.PolicyOPASubSys][config.Default] = config.KVS{
		config.KV{
			Key:   URL,
			Value: opaArgs.URL.String(),
		},
		config.KV{
			Key:   AuthToken,
			Value: opaArgs.AuthToken,
		},
	}

		// Do not enable storage-class if no settings found.
		return
	}
	s[config.StorageClassSubSys][config.Default] = config.KVS{
		config.KV{
			Key:   ClassStandard,
			Value: cfg.Standard.String(),
		},
		config.KV{
			Key:   ClassRRS,
			Value: cfg.RRS.String(),
		},
	}

    the key value sent in the query parameter automatically and provides it as the
    dependency result. But it doesn't define how to send that API key to the client.

    ## Usage

    Create an instance object and use that object as the dependency in `Depends()`.

    The dependency result will be a string containing the key value.

    ## Example

    ```python

  abstract void setCountCheckReturnValue(E element, int count);

  /**
   * Call the {@code setCount()} method under test, but do not check its return value. Callers
   * should use this method over {@link #setCountCheckReturnValue(Object, int)} when they expect
   * {@code setCount()} to throw an exception, as checking the return value could produce an

    @see <a href="/guides/mini/guide-using-toolchains.html">Guide to Using Toolchains</a>
    ]]></description>

  <defaults>
    <default>
      <key>package</key>
      <value>org.apache.maven.toolchain.model</value>
    </default>
  </defaults>

  <classes>
    <class java.clone="deep">
      <name>TrackableBase</name>
      <version>1.1.0+</version>
      <description>

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

The `str | None` (Python 3.10+) or `Union` in `Union[str, None]` (Python 3.8+) is not used by FastAPI to determine that the value is not required, it will know it's not required because it has a default value of `= None`.