public void testAdd_firstFewWithSuccess() {
    int COUNT = 400;

    when(backingMap.get(KEY)).thenReturn(null);
    when(backingMap.putIfAbsent(eq(KEY), isA(AtomicInteger.class))).thenReturn(null);

    assertEquals(0, multiset.add(KEY, COUNT));
  }

  public void testAdd_laterFewWithSuccess() {
    int INITIAL_COUNT = 32;
    int COUNT_TO_ADD = 400;

    AtomicInteger initial = new AtomicInteger(INITIAL_COUNT);

    assertEquals((Integer) 2, it.next());
    it.remove();
    // After this remove, 400 has moved up and 20 down past cursor
    assertTrue("Heap is not intact after remove", mmHeap.isIntact());
    assertEquals((Integer) 10, it.next());
    assertEquals((Integer) 3, it.next());
    it.remove();
    // After this remove, 400 moved down again and 500 up past the cursor

* etc.

In these cases, you would normally return an **HTTP status code** in the range of **400** (from 400 to 499).

This is similar to the 200 HTTP status codes (from 200 to 299). Those "200" status codes mean that somehow there was a "success" in the request.

The status codes in the 400 range mean that there was an error from the client.

Remember all those **"404 Not Found"** errors (and jokes)?

    class ErrorModelV1(BaseModel):
        detail: str

    app = FastAPI()

    with pytest.raises(PydanticV1NotSupportedError):

        @app.get(
            "/responses", response_model=None, responses={400: {"model": ErrorModelV1}}
        )
        def endpoint():  # pragma: no cover
            return {"ok": True}


def test_raises_pydantic_v1_model_in_union() -> None:
    class ModelV1A(BaseModel):

@font-face {
    font-family: cash-market;
    src: url("https://cash-f.squarecdn.com/static/fonts/cash-market/v2/CashMarket-Regular.woff2") format("woff2");
    font-weight: 400;
    font-style: normal
}

@font-face {
    font-family: cash-market;
    src: url("https://cash-f.squarecdn.com/static/fonts/cash-market/v2/CashMarket-Medium.woff2") format("woff2");
    font-weight: 500;
    font-style: normal
}

@font-face {

func errJSONParsingError(err error) *s3Error {
	return &s3Error{
		code:       "JSONParsingError",
		message:    fmt.Sprintf("Encountered an error parsing the JSON file: %v. Check the file and try again.", err),
		statusCode: 400,
		cause:      err,
	}

        -d "$data" \
        -w "\n%{http_code}" \
        2>/dev/null)

    local http_code=$(echo "$response" | tail -n1)
    local body=$(echo "$response" | head -n -1)

    if [[ "$http_code" -ge 400 ]]; then
        printf "Error: HTTP %s - %s\n" "$http_code" "$body" >&2
        exit 1
    fi

    echo "$body"
}

main() {
    WRAPPER_VERSION="${1:-}"

        raise credentials_exception
    return user


async def get_current_active_user(current_user: User = Depends(get_current_user)):
    if current_user.disabled:
        raise HTTPException(status_code=400, detail="Inactive user")
    return current_user


@app.post("/token")
async def login_for_access_token(
    form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:

            }

            executor.accept(httpRequest, (response, entity) -> {
                final int httpStatusCode = response.getCode();
                if (httpStatusCode < 400 || httpStatusCode == 401) {
                    parseTokenPage(tokenPattern, responseParams, entity);
                } else {
                    String content;
                    try {

* **`400 - 499`** は「クライアントエラー」のレスポンスのためのものです。これらは、おそらく最も多用するであろう2番目のタイプです。
    * 例えば、`404`は「Not Found」レスポンスです。
    * クライアントからの一般的なエラーについては、`400`を使用することができます。
* `500 - 599` はサーバーエラーのためのものです。これらを直接使うことはほとんどありません。アプリケーションコードやサーバーのどこかで何か問題が発生した場合、これらのステータスコードのいずれかが自動的に返されます。

/// tip | 豆知識