public class UserAgentHelper {
    protected static final String USER_AGENT = "user-agent";

    protected static final String USER_AGENT_TYPE = "ViewHelper.UserAgent";

    public UserAgentType getUserAgentType() {
        return LaRequestUtil.getOptionalRequest().map(request -> {
            UserAgentType uaType = (UserAgentType) request.getAttribute(USER_AGENT_TYPE);
            if (uaType == null) {

        }

        final String userAgent = getUserAgent();
        if (StringUtil.isNotBlank(userAgent)) {
            if (userAgent.startsWith(Constants.CRAWLING_USER_AGENT_PREFIX) && userAgent.endsWith(Constants.CRAWLING_USER_AGENT_SUFFIX)) {
                paramMap.put(Client.USER_AGENT, fessConfig.getUserAgentName());
            } else {
                paramMap.put(Client.USER_AGENT, userAgent);
            }
        } else {

from typing import Annotated

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: Annotated[str | None, Header()] = None):

from typing import Annotated, Union

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: Annotated[Union[str, None], Header()] = None):

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: str | None = Header(default=None)):

from typing import Union

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: Union[str, None] = Header(default=None)):

from typing import Union

from fastapi import FastAPI, Header
from typing_extensions import Annotated

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: Annotated[Union[str, None], Header()] = None):

            public static final String PROXY_PORT = HcHttpClient.PROXY_PORT_PROPERTY;
            public static final String PROXY_HOST = HcHttpClient.PROXY_HOST_PROPERTY;
            public static final String USER_AGENT = HcHttpClient.USER_AGENT_PROPERTY;
        }

        // xpath.*
        public static class XPath {
            public static final String DEFAULT_LANG = "default.lang";

 */
package okhttp3.internal.http

import java.io.IOException
import okhttp3.Cookie
import okhttp3.CookieJar
import okhttp3.Interceptor
import okhttp3.Response
import okhttp3.internal.USER_AGENT
import okhttp3.internal.toHostHeader
import okio.GzipSource
import okio.buffer

/**
 * Bridges from application code to network code. First it builds a network request from a user

        final SetOnce<Map<String, Object>> initParamMapSet = new SetOnce<>();
        WebConfig webConfig = new WebConfig();
        webConfig.setUserAgent(Constants.CRAWLING_USER_AGENT_PREFIX + "1.0" + Constants.CRAWLING_USER_AGENT_SUFFIX);
        CrawlerClientFactory crawlerClientFactory = webConfig.initializeClientFactory(() -> new CrawlerClientFactory() {
            public void setInitParameterMap(final Map<String, Object> params) {