} else if (parameterType.equals(Double.TYPE)) {
                    methodKey.append("java.lang.Double");
                } else if (parameterType.equals(Float.TYPE)) {
                    methodKey.append("java.lang.Float");
                } else if (parameterType.equals(Integer.TYPE)) {
                    methodKey.append("java.lang.Integer");
                } else if (parameterType.equals(Long.TYPE)) {

                            <la:message key="labels.bad_word_configuration"/>
                        </h1>
                    </div>
                    <div class="col-sm-6">
                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item active"><la:link href="/admin/badword">
                                <la:message key="labels.bad_word_link_list"/>
                            </la:link></li>

                            <la:message key="labels.bad_word_title_details"/>
                        </h1>
                    </div>
                    <div class="col-sm-6">
                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item"><la:link href="/admin/badword">
                                <la:message key="labels.bad_word_link_list"/>
                            </la:link></li>

                            <la:message key="labels.bad_word_title_details"/>
                        </h1>
                    </div>
                    <div class="col-sm-6">
                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item active"><la:link href="/admin/badword">
                                <la:message key="labels.bad_word_link_list"/>
                            </la:link></li>

                            <la:message key="labels.dict_kuromoji_title"/>
                        </h1>
                    </div>
                    <div class="col-sm-6">
                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item"><la:link href="/admin/dict">
                                <la:message key="labels.dict_list_link"/>
                            </la:link></li>

  @Override
  int readInt();

  @CanIgnoreReturnValue // to skip some bytes
  @Override
  long readLong();

  @CanIgnoreReturnValue // to skip some bytes
  @Override
  float readFloat();

  @CanIgnoreReturnValue // to skip some bytes
  @Override
  double readDouble();

  @CanIgnoreReturnValue // to skip a line
  @Override
  @Nullable String readLine();

        allow_redirects=False, auth=(client_id, client_secret))

    print('body: ' + id_token_response.text)

    # we can now use the id_token as much as we want to access protected resources.
    tokens = json.loads(id_token_response.text)
    id_token = tokens['id_token']

    response = sts_client.assume_role_with_web_identity(
        RoleArn='arn:aws:iam::123456789012:user/svc-internal-api',
        RoleSessionName='test',

      ],
      "msg": "Input should be a valid integer, unable to parse string as an integer",
      "input": "foo"
    }
  ]
}
```

경로 매개변수 `item_id`가 `int`가 아닌 `"foo"` 값을 가졌기 때문입니다.

`int` 대신 `float`을 제공하면(예: [http://127.0.0.1:8000/items/4.2](http://127.0.0.1:8000/items/4.2)) 동일한 오류가 나타납니다.

/// check | 확인

즉, 파이썬 타입 선언을 하면 **FastAPI**는 데이터 검증을 합니다.

또한 오류에는 검증을 통과하지 못한 지점이 정확히 명시됩니다.

```Python hl_lines="2  7-10 23-25"
from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool | None = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: str | None = None):

    /** Custom post-tags for highlighting (null uses OpenSearch defaults). */
    private String[] postTags;

    /**
     * Default constructor that initializes highlighting settings from Fess configuration.
     * Loads default values for type, fragment size, number of fragments, and fragment offset.
     */
    public HighlightInfo() {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();