}

    /**
     * Extracts and parses parameters from the request query string.
     * Applies the specified character encoding to decode parameter values.
     *
     * @param request the HTTP request containing the query string
     * @param enc the character encoding to use for decoding
     * @return a map of parameter names to their decoded values

        } ?: return // Expected a value.

      val replaced = parameters.put(peek, parameterValue)
      peek = null
      if (replaced != null) return // Unexpected duplicate parameter.
      if (!skipCommasAndWhitespace() && !exhausted()) return // Expected ',' or EOF.
    }
    result.add(Challenge(schemeName, parameters))
  }
}

/** Returns true if any commas were skipped. */

    }

    /**
     * Builds parameter maps for search initialization, creating both query strings
     * and form inputs for the given parameters.
     *
     * @param paramMap the parameter map to process
     * @param queryKey the key for storing query string parameters
     * @param formKey the key for storing form input parameters
     */

        };

        // Test with nested parameters
        Map<String, Object> nestedParams = new HashMap<>();
        Map<String, Object> innerMap = new HashMap<>();
        innerMap.put("innerKey", "innerValue");
        nestedParams.put("nested", innerMap);

        assertNotNull(queryRescorer.evaluate(nestedParams));

        // Test without nested parameters
        Map<String, Object> flatParams = new HashMap<>();

        default:
            return "Unknown error: 0x" + Integer.toHexString(returnCode);
        }
    }

    /**
     * Encodes the witness RPC message parameters to NDR format.
     * Subclasses must implement this method to encode their specific parameters.
     *
     * @param buf the NDR buffer to encode into
     * @throws NdrException if encoding fails
     */

In this case, this `__call__` is what **FastAPI** will use to check for additional parameters and sub-dependencies, and this is what will be called to pass a value to the parameter in your *path operation function* later.

## Parameterize the instance { #parameterize-the-instance }

And now, we can use `__init__` to declare the parameters of the instance that we can use to "parameterize" the dependency:

      ImmutableListMultimap.of("a", "1", "a", "2", "b", "3");

  public void testGetParameters() {
    assertEquals(ImmutableListMultimap.of(), MediaType.parse("text/plain").parameters());
    assertEquals(
        ImmutableListMultimap.of("charset", "utf-8"),
        MediaType.parse("application/atom+xml; charset=utf-8").parameters());

```

///

## Import `File` and `Form` { #import-file-and-form }

{* ../../docs_src/request_forms_and_files/tutorial001_an_py39.py hl[3] *}

## Define `File` and `Form` parameters { #define-file-and-form-parameters }

Create file and form parameters the same way you would for `Body` or `Query`:

{* ../../docs_src/request_forms_and_files/tutorial001_an_py39.py hl[10:12] *}

    /**
     * Constructs a new HostIntervalController with default parameters.
     */
    public HostIntervalController() {
    }

    /**
     * Constructs a new HostIntervalController with the specified parameters.
     *
     * @param params the parameters to configure the interval controller
     */
    public HostIntervalController(final Map<String, Long> params) {

        }
    }

    /**
     * Retrieves an initialization parameter, converting it to the specified class type.
     * @param <T> The type of the parameter.
     * @param key The key of the parameter.
     * @param defaultValue The default value if the parameter is not found.
     * @param clazz The class type to convert the parameter to.
     * @return The parameter value, or the default value if not found.
     */