[discuss.codelibs.org](https://discuss.codelibs.org/c/FessEN/)

## Getting Started

There are 2 ways to try Fess. The first is to download and install yourself. The second is to use [Docker](https://www.docker.com/products/docker-engine).

### Download and Install/Run

Fess 15.0 is now available and can be downloaded on the [Releases page](https://github.com/codelibs/fess/releases "download"). Downloads come in 3 flavors: deb, rpm, zip.

 * Graphically, this is the specification of a straight line on a plane. The transformation can be
 * expressed as {@code y = m * x + c} for finite {@code m} and {@code c}, unless it is a vertical
 * transformation in which case {@code x} has a constant value for all {@code y}. In the
 * non-vertical case, {@code m} is the slope of the transformation (and a horizontal transformation
 * has zero slope).

import jakarta.annotation.PostConstruct;

/**
 * View class for managing facet query configurations and their display.
 * This class handles the setup and organization of query facets for the search interface,
 * including automatic generation of file type facets and custom query mappings.
 */
public class FacetQueryView {
    /** Logger instance for this class */

 * the "running" state need to perform a periodic task. Subclasses can implement {@link #startUp},
 * {@link #shutDown} and also a {@link #runOneIteration} method that will be executed periodically.
 *
 * <p>This class uses the {@link ScheduledExecutorService} returned from {@link #executor} to run

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.helper;

import org.lastaflute.web.util.LaRequestUtil;

/**
 * Helper class for detecting and categorizing user agent types from HTTP requests.
 * This class analyzes the User-Agent header to determine which browser type is being used
 * and caches the result in the request attribute for performance optimization.

/**
 * The {@link CrawlerContext} class holds the context information for a crawler execution.
 * It contains various attributes related to the crawler's state, configuration, and runtime data.
 * This class provides methods to access and modify these attributes, allowing for control and monitoring
 * of the crawler's behavior.
 *
 * <p>
 * The context includes information such as the session ID, active thread count, access count, crawler status,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.EnumMap;
import java.util.Map;

/**
 * A {@code BiMap} backed by two {@code EnumMap} instances. Null keys and values are not permitted.
 * An {@code EnumBiMap} and its inverse are both serializable.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#bimap">{@code BiMap}</a>.
 *

/**
 * QueryHelper is responsible for building and managing OpenSearch queries for Fess search functionality.
 * It handles query construction, role-based access control, boost functions, sorting, and search preferences.
 * This class serves as the central component for translating user search requests into properly formatted
 * OpenSearch queries with appropriate filters and scoring mechanisms.
 */
public class QueryHelper {

    /**

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.crawler.client;

import java.util.Map;

import org.codelibs.fess.crawler.entity.RequestData;
import org.codelibs.fess.crawler.entity.ResponseData;

/**
 * Interface representing a client for a web crawler.
 * This client is responsible for executing requests and handling responses.