com.liferay.portal.kernel.servlet.FileTimestampUtil Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of com.liferay.portal.kernel Show documentation

Contains interfaces for the portal services. Interfaces are only loaded by the global class loader and are shared by all plugins.

There is a newer version: 141.0.0

Show newest version

/**
 * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 */

package com.liferay.portal.kernel.servlet;

import com.liferay.petra.string.CharPool;
import com.liferay.portal.kernel.log.Log;
import com.liferay.portal.kernel.log.LogFactoryUtil;
import com.liferay.portal.kernel.util.URLUtil;
import com.liferay.portal.kernel.util.Validator;

import java.io.File;
import java.io.IOException;

import java.net.URL;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import javax.servlet.ServletContext;

/**
 * @author Shuyang Zhou
 */
public class FileTimestampUtil {

	public static long getTimestamp(
		ServletContext servletContext, String path) {

		if (Validator.isNull(path)) {
			return 0;
		}

		if (path.charAt(0) != CharPool.SLASH) {
			return 0;
		}

		String timestampsCacheKey = FileTimestampUtil.class.getName();

		Map timestamps =
			(Map)servletContext.getAttribute(timestampsCacheKey);

		if (timestamps == null) {
			timestamps = new ConcurrentHashMap<>();

			servletContext.setAttribute(timestampsCacheKey, timestamps);
		}

		Long timestamp = timestamps.get(path);

		if (timestamp != null) {
			return timestamp;
		}

		timestamp = 0L;

		String uriRealPath = servletContext.getRealPath(path);

		if (uriRealPath != null) {
			File uriFile = new File(uriRealPath);

			if (uriFile.exists()) {
				timestamp = uriFile.lastModified();

				timestamps.put(path, timestamp);

				return timestamp;
			}
		}

		try {
			URL url = servletContext.getResource(path);

			if (url == null) {
				_log.error("Resource URL for " + path + " is null");
			}
			else {
				timestamp = URLUtil.getLastModifiedTime(url);
			}
		}
		catch (IOException ioException) {
			_log.error(ioException, ioException);
		}

		timestamps.put(path, timestamp);

		return timestamp;
	}

	public static void reset(ServletContext servletContext) {
		String timestampsCacheKey = FileTimestampUtil.class.getName();

		servletContext.removeAttribute(timestampsCacheKey);
	}

	private static final Log _log = LogFactoryUtil.getLog(
		FileTimestampUtil.class);

}