<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-t09</groupId>
  <artifactId>p0</artifactId>
  <packaging>pom</packaging>
  <name>p0</name>
  <version>1.0</version>
  <organization>
    <name>Codehaus</name>
  </organization>

  <dependencyManagement>

    <dependencies>

      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t09-a</artifactId>
        <version>1.0</version>

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item = Body(
        examples=[
            {
                "name": "Foo",
                "description": "A very nice Item",
                "price": 35.4,

                "schemas": {
                    "Item": {
                        "title": "Item",
                        "required": ["name", "price"],
                        "type": "object",
                        "properties": {
                            "name": {"title": "Name", "type": "string"},
                            "description": {
                                "title": "Description",

        rolePager.id = "testId";
        rolePager.name = "testName";
        rolePager.versionNo = "1";
        rolePager.setAllRecordCount(100);
        rolePager.setAllPageCount(10);
        rolePager.setExistPrePage(true);
        rolePager.setExistNextPage(true);

        rolePager.clear();

        assertNull(rolePager.id);
        assertNull(rolePager.name);
        assertNull(rolePager.versionNo);

import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Specifies the priority of a bean implementation when multiple implementations
 * of the same type are available.
 * <p>
 * Higher values indicate higher priority. When multiple implementations of the same
 * type exist, the one with the highest priority will be selected for injection.
 * <p>
 * Example usage:
 * <pre>
 * {@literal @}Priority(100)

import importlib
import os
import shutil

import pytest
from fastapi.testclient import TestClient
from inline_snapshot import snapshot

from tests.utils import needs_py310, workdir_lock


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial002_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

举个例子，看这段函数：

```python
from typing import Optional


def say_hi(name: Optional[str]):
    print(f"Hey {name}!")
```

参数 `name` 被定义为 `Optional[str]`，但它并不是“可选”的，你不能不传这个参数就调用函数：

```Python
say_hi()  # 哎呀，这会报错！😱
```

参数 `name` 仍然是必填的（不是“可选”），因为它没有默认值。不过，`name` 接受 `None` 作为取值：

```Python
say_hi(name=None)  # 这样可以，None 是有效的 🎉
```

好消息是，在大多数情况下，你可以直接使用 `|` 来定义类型联合：

```python

        public void setParameterValues(String name, String[] values) {
            parameters.put(name, values);
        }

        public void setParameter(String name, String value) {
            singleParameters.put(name, value);
        }

        @Override
        public String[] getParameterValues(String name) {
            return parameters.get(name);
        }

        @Override

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Annotated[
        Item,
        Body(
            examples=[
                {
                    "name": "Foo",
                    "description": "A very nice Item",