import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.opensearch.client.SearchEngineClient;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;
import org.dbflute.optional.OptionalEntity;
import org.lastaflute.web.Execute;
import org.lastaflute.web.response.HtmlResponse;
import org.lastaflute.web.response.render.RenderData;
import org.lastaflute.web.ruts.process.ActionRuntime;

import org.codelibs.fess.query.QueryFieldConfig;
import org.codelibs.fess.query.parser.QueryParser;
import org.codelibs.fess.score.QueryRescorer;
import org.codelibs.fess.util.ComponentUtil;
import org.dbflute.optional.OptionalThing;
import org.lastaflute.core.message.UserMessages;
import org.lastaflute.web.util.LaRequestUtil;
import org.opensearch.action.search.SearchRequestBuilder;
import org.opensearch.index.query.BoolQueryBuilder;

   *
   * @since 11.0
   */
  public static <T> Optional<T> tryFind(Iterator<T> iterator, Predicate<? super T> predicate) {
    checkNotNull(iterator);
    checkNotNull(predicate);
    while (iterator.hasNext()) {
      T t = iterator.next();
      if (predicate.apply(t)) {
        return Optional.of(t);
      }
    }
    return Optional.absent();
  }

  /**

   *
   * @since 11.0
   */
  public static <T> Optional<T> tryFind(Iterator<T> iterator, Predicate<? super T> predicate) {
    checkNotNull(iterator);
    checkNotNull(predicate);
    while (iterator.hasNext()) {
      T t = iterator.next();
      if (predicate.apply(t)) {
        return Optional.of(t);
      }
    }
    return Optional.absent();
  }

  /**

     * @throws PACDecodingException if a PAC decoding error occurs
     */
    @Test
    void testGettersWithNull() throws IOException, PACDecodingException {
        // Build a token with no optional fields
        ASN1EncodableVector vector = new ASN1EncodableVector();
        DERSequence sequence = new DERSequence(vector);
        byte[] encoded = new DERTaggedObject(false, BERTags.APPLICATION, 1, sequence).getEncoded();

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

但如果你改為造訪：

```
http://127.0.0.1:8000/items/?skip=20
```

函式中的參數值會是：

* `skip=20`：因為你在 URL 中設定了它
* `limit=10`：因為那是預設值

## 選用參數 { #optional-parameters }

同樣地，你可以將預設值設為 `None` 來宣告選用的查詢參數：

{* ../../docs_src/query_params/tutorial002_py310.py hl[7] *}

在這種情況下，函式參數 `q` 為選用，且預設為 `None`。

/// check | 注意

import org.codelibs.fess.opensearch.config.exentity.FailureUrl;
import org.codelibs.fess.util.ComponentUtil;
import org.dbflute.cbean.result.PagingResultBean;
import org.dbflute.optional.OptionalEntity;

import jakarta.annotation.Resource;

/**
 * Service class for managing failure URLs that occur during web crawling.
 * Provides functionality to store, retrieve, and manage failed crawling attempts

import org.codelibs.fess.opensearch.config.exentity.FileConfig;
import org.codelibs.fess.util.ParameterUtil;
import org.dbflute.cbean.result.ListResultBean;
import org.dbflute.cbean.result.PagingResultBean;
import org.dbflute.optional.OptionalEntity;

import jakarta.annotation.Resource;

/**
 * Service class for managing file configuration operations.
 * This service provides CRUD operations for file crawler configurations,

If it doesn't receive it, it returns an HTTP 401 "Unauthorized" error.

And returns a header `WWW-Authenticate` with a value of `Basic`, and an optional `realm` parameter.

That tells the browser to show the integrated prompt for a username and password.

Then, when you type that username and password, the browser sends them in the header automatically.

import org.codelibs.fess.dict.DictionaryManager;
import org.codelibs.fess.dict.mapping.CharMappingFile;
import org.codelibs.fess.dict.mapping.CharMappingItem;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.dbflute.optional.OptionalEntity;

import jakarta.annotation.Resource;

/**
 * Service class for managing character mapping operations.
 * <p>
 * This service handles character mapping management including CRUD operations