import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.util.ComponentUtil;
import org.dbflute.optional.OptionalObject;
import org.dbflute.optional.OptionalThing;
import org.dbflute.util.DfTypeUtil;
import org.lastaflute.web.ruts.process.ActionRuntime;
import org.lastaflute.web.servlet.request.RequestManager;

   *     in this instance of the Java virtual machine
   */
  public Optional<Charset> charset() {
    // racy single-check idiom, this is safe because Optional is immutable.
    Optional<Charset> local = parsedCharset;
    if (local == null) {
      String value = null;
      local = Optional.absent();
      for (String currentValue : parameters.get(CHARSET_ATTRIBUTE)) {
        if (value == null) {

    @Nonnull
    DependencyScope getScope();

    /**
     * Returns whether the dependency is optional or mandatory.
     * Unlike {@link DependencyCoordinates}, the obligation of a {@code Dependency} is always present.
     * The value is computed during the dependencies collection phase.
     *
     * @return {@code true} if the dependency is optional, or {@code false} if mandatory
     * @see DependencyCoordinates#getOptional()
     */

   */
  private int findSuffixOfType(Optional<PublicSuffixType> desiredType) {
    int partsSize = parts.size();

    for (int i = 0; i < partsSize; i++) {
      String ancestorName = DOT_JOINER.join(parts.subList(i, partsSize));

      if (i > 0
          && matchesType(
              desiredType, Optional.fromNullable(PublicSuffixPatterns.UNDER.get(ancestorName)))) {
        return i - 1;

import org.codelibs.fess.opensearch.user.exbhv.UserBhv;
import org.codelibs.fess.opensearch.user.exentity.Role;
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 roles.
 */
public class RoleService {

    /**
     * The behavior for roles.
     */
    @Resource

import org.codelibs.fess.opensearch.config.exentity.DataConfig;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.optional.OptionalThing;
import org.lastaflute.web.Execute;
import org.lastaflute.web.response.HtmlResponse;
import org.lastaflute.web.response.render.RenderData;

import org.codelibs.fess.opensearch.config.exentity.PathMapping;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.optional.OptionalThing;
import org.lastaflute.web.Execute;
import org.lastaflute.web.response.HtmlResponse;
import org.lastaflute.web.response.render.RenderData;

This is not a limitation of **FastAPI**, it's part of the HTTP protocol.

///

## Optional File Upload { #optional-file-upload }

You can make a file optional by using standard type annotations and setting a default value of `None`:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

import org.codelibs.fess.util.BooleanFunction;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.QueryResponseList;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.optional.OptionalThing;
import org.dbflute.util.DfTypeUtil;
import org.lastaflute.taglib.function.LaFunctions;
import org.lastaflute.web.util.LaRequestUtil;
import org.lastaflute.web.util.LaResponseUtil;

import org.codelibs.fess.opensearch.config.exbhv.KeyMatchBhv;
import org.codelibs.fess.opensearch.config.exentity.KeyMatch;
import org.dbflute.cbean.result.PagingResultBean;
import org.dbflute.optional.OptionalEntity;

import jakarta.annotation.Resource;

/**
 * Service class for KeyMatch.
 */
public class KeyMatchService extends FessAppService {

    /** The KeyMatch behavior. */
    @Resource