/*
 * Copyright (C) 2018, Konrad Windszus <konrad_w@gmx.de> and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */
package org.eclipse.jgit.internal.transport.http;

import java.nio.file.Path;

import org.eclipse.jgit.transport.HttpConfig;
import org.eclipse.jgit.util.LRUMap;

A cache of all known cookie files (NetscapeCookieFile). May contain at most n entries, where the least-recently used one is evicted as soon as more entries are added. The maximum number of entries (=n) can be set via the git config key http.cookieFileCacheLimit. By default it is set to 10. 

The cache is global, i.e. it is shared among all consumers within the same
Java process.
See Also:
NetscapeCookieFile/**
 * A cache of all known cookie files ({@link NetscapeCookieFile}). May contain
 * at most {@code n} entries, where the least-recently used one is evicted as
 * soon as more entries are added. The maximum number of entries (={@code n})
 * can be set via the git config key {@code http.cookieFileCacheLimit}. By
 * default it is set to 10.
 * <p>
 * The cache is global, i.e. it is shared among all consumers within the same
 * Java process.
 *
 * @see NetscapeCookieFile
 *
 */
public class NetscapeCookieFileCache {

	private final LRUMap<Path, NetscapeCookieFile> cookieFileMap;

	private static NetscapeCookieFileCache instance;

	private NetscapeCookieFileCache(HttpConfig config) {
		cookieFileMap = new LRUMap<>(config.getCookieFileCacheLimit(),
				config.getCookieFileCacheLimit());
	}

	
Params:
config – 
           the config which defines the limit for this cache
Returns:
the singleton instance of the cookie file cache. If the cache has
        already been created the given config is ignored (even if it
        differs from the config, with which the cache has originally been
        created)/**
	 * @param config
	 *            the config which defines the limit for this cache
	 * @return the singleton instance of the cookie file cache. If the cache has
	 *         already been created the given config is ignored (even if it
	 *         differs from the config, with which the cache has originally been
	 *         created)
	 */
	public static NetscapeCookieFileCache getInstance(HttpConfig config) {
		if (instance == null) {
			return new NetscapeCookieFileCache(config);
		}
		return instance;
	}

	
Params:
path – 
           the path of the cookie file to retrieve
Returns:
the cache entry belonging to the requested file/**
	 * @param path
	 *            the path of the cookie file to retrieve
	 * @return the cache entry belonging to the requested file
	 */
	public NetscapeCookieFile getEntry(Path path) {
		if (!cookieFileMap.containsKey(path)) {
			synchronized (NetscapeCookieFileCache.class) {
				if (!cookieFileMap.containsKey(path)) {
					cookieFileMap.put(path, new NetscapeCookieFile(path));
				}
			}
		}
		return cookieFileMap.get(path);
	}

}