from typing import Optional

from fastapi import FastAPI
from fastapi.params import Param
from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/items/")
def read_items(q: Optional[str] = Param(default=None)):  # type: ignore
    return {"q": q}


client = TestClient(app)


def test_default_param_query_none():
    response = client.get("/items/")
    assert response.status_code == 200, response.text

        final MyBean myBean = new MyBean();
        final BeanDesc beanDesc = new BeanDescImpl(MyBean.class);
        final PropertyDesc propDesc = beanDesc.getPropertyDesc("str");
        propDesc.setValue(myBean, Integer.valueOf(1));
        assertThat(myBean.str, is("1"));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testSetNullToString() throws Exception {

* Data conversion
* Data validation
* Automatic documentation

## Special types and validation { #special-types-and-validation }

Apart from normal singular types like `str`, `int`, `float`, etc. you can use more complex singular types that inherit from `str`.

* Валидацию данных
* Автоматическую документацию

## Особые типы и валидация { #special-types-and-validation }

Помимо обычных простых типов, таких как `str`, `int`, `float` и т.д., вы можете использовать более сложные простые типы, которые наследуются от `str`.

            }
            System.arraycopy(Strings.getUNIBytes(str), 0, dst, dstIndex, str.length() * 2);
            dstIndex += str.length() * 2;
            dst[dstIndex] = (byte) '\0';
            dstIndex++;
            dst[dstIndex++] = (byte) '\0';
        } else {
            final byte[] b = Strings.getOEMBytes(str, this.getConfig());
            System.arraycopy(b, 0, dst, dstIndex, b.length);

from fastapi import Depends, FastAPI

app = FastAPI()


fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]


class CommonQueryParams:
    def __init__(self, q: str | None = None, skip: int = 0, limit: int = 100):
        self.q = q
        self.skip = skip
        self.limit = limit


@app.get("/items/")
async def read_items(commons: Annotated[Any, Depends(CommonQueryParams)]):

        bi += 4;
        sid = new SID(buf, bi);
        return size;
    }

    void appendCol(final StringBuffer sb, final String str, final int width) {
        sb.append(str);
        final int count = width - str.length();
        for (int i = 0; i < count; i++) {
            sb.append(' ');
        }
    }

    /**
     * Return a string represeting this ACE.
     * <p>

* 数据转换
* 数据校验
* 自动生成文档

## 特殊的类型和校验

除了普通的单一值类型（如 `str`、`int`、`float` 等）外，你还可以使用从 `str` 继承的更复杂的单一值类型。

要了解所有的可用选项，请查看关于 <a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">来自 Pydantic 的外部类型</a> 的文档。你将在下一章节中看到一些示例。

例如，在 `Image` 模型中我们有一个 `url` 字段，我们可以把它声明为 Pydantic 的 `HttpUrl`，而不是 `str`：

{* ../../docs_src/body_nested_models/tutorial005_py310.py hl[2,8] *}

    }

    public static String normalizeText(final String str, final int initialCapacity, final int maxAlphanumTermSize,
            final int maxSymbolTermSize, final boolean removeDuplication) {
        if (str == null) {
            return StringUtil.EMPTY;
        }
        try (final Reader reader = new StringReader(str)) {

* Wenn der Parameter vom Typ eines **Pydantic-Modells** ist, wird er als Request**body** interpretiert.

/// note | Hinweis

FastAPI weiß, dass der Wert von `q` nicht erforderlich ist, aufgrund des definierten Defaultwertes `= None`.