| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.commons.configuration2.io; |
| |
| import java.io.File; |
| import java.net.URL; |
| |
| import org.apache.commons.lang3.StringUtils; |
| |
| /** |
| * <p> |
| * A specialized implementation of {@code FileLocationStrategy} which searches |
| * for files in the user's home directory or another special configurable |
| * directory. |
| * </p> |
| * <p> |
| * This strategy implementation ignores the URL stored in the passed in |
| * {@link FileLocator}. It constructs a file path from the configured home |
| * directory (which is the user's home directory per default, but can be changed |
| * to another path), optionally the base path, and the file name. If the |
| * resulting path points to an existing file, its URL is returned. |
| * </p> |
| * <p> |
| * When constructing an instance it can be configured whether the base path |
| * should be taken into account. If this option is set, the base path is |
| * appended to the home directory if it is not <b>null</b>. This is useful for |
| * instance to select a specific sub directory of the user's home directory. If |
| * this option is set to <b>false</b>, the base path is always ignored, and only |
| * the file name is evaluated. |
| * </p> |
| * |
| * @version $Id$ |
| */ |
| public class HomeDirectoryLocationStrategy implements FileLocationStrategy |
| { |
| /** Constant for the system property with the user's home directory. */ |
| private static final String PROP_HOME = "user.home"; |
| |
| /** The home directory to be searched for the requested file. */ |
| private final String homeDirectory; |
| |
| /** The flag whether the base path is to be taken into account. */ |
| private final boolean evaluateBasePath; |
| |
| /** |
| * Creates a new instance of {@code HomeDirectoryLocationStrategy} and |
| * initializes it with the specified settings. |
| * |
| * @param homeDir the path to the home directory (can be <b>null</b>) |
| * @param withBasePath a flag whether the base path should be evaluated |
| */ |
| public HomeDirectoryLocationStrategy(String homeDir, boolean withBasePath) |
| { |
| homeDirectory = fetchHomeDirectory(homeDir); |
| evaluateBasePath = withBasePath; |
| } |
| |
| /** |
| * Creates a new instance of {@code HomeDirectoryLocationStrategy} and |
| * initializes the base path flag. The home directory is set to the user's |
| * home directory. |
| * |
| * @param withBasePath a flag whether the base path should be evaluated |
| */ |
| public HomeDirectoryLocationStrategy(boolean withBasePath) |
| { |
| this(null, withBasePath); |
| } |
| |
| /** |
| * Creates a new instance of {@code HomeDirectoryLocationStrategy} with |
| * default settings. The home directory is set to the user's home directory. |
| * The base path flag is set to <b>false</b> (which means that the base path |
| * is ignored). |
| */ |
| public HomeDirectoryLocationStrategy() |
| { |
| this(false); |
| } |
| |
| /** |
| * Returns the home directory. In this directory the strategy searches for |
| * files. |
| * |
| * @return the home directory used by this object |
| */ |
| public String getHomeDirectory() |
| { |
| return homeDirectory; |
| } |
| |
| /** |
| * Returns a flag whether the base path is to be taken into account when |
| * searching for a file. |
| * |
| * @return the flag whether the base path is evaluated |
| */ |
| public boolean isEvaluateBasePath() |
| { |
| return evaluateBasePath; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation searches in the home directory for a |
| * file described by the passed in {@code FileLocator}. If the locator |
| * defines a base path and the {@code evaluateBasePath} property is |
| * <b>true</b>, a sub directory of the home directory is searched. |
| */ |
| @Override |
| public URL locate(FileSystem fileSystem, FileLocator locator) |
| { |
| if (StringUtils.isNotEmpty(locator.getFileName())) |
| { |
| String basePath = fetchBasePath(locator); |
| File file = |
| FileLocatorUtils.constructFile(basePath, |
| locator.getFileName()); |
| if (file.isFile()) |
| { |
| return FileLocatorUtils.convertFileToURL(file); |
| } |
| } |
| |
| return null; |
| } |
| |
| /** |
| * Determines the base path to be used for the current locate() operation. |
| * |
| * @param locator the {@code FileLocator} |
| * @return the base path to be used |
| */ |
| private String fetchBasePath(FileLocator locator) |
| { |
| if (isEvaluateBasePath() |
| && StringUtils.isNotEmpty(locator.getBasePath())) |
| { |
| return FileLocatorUtils.appendPath(getHomeDirectory(), |
| locator.getBasePath()); |
| } |
| else |
| { |
| return getHomeDirectory(); |
| } |
| } |
| |
| /** |
| * Obtains the home directory to be used by a new instance. If a directory |
| * name is provided, it is used. Otherwise, the user's home directory is |
| * looked up. |
| * |
| * @param homeDir the passed in home directory |
| * @return the directory to be used |
| */ |
| private static String fetchHomeDirectory(String homeDir) |
| { |
| return (homeDir != null) ? homeDir : System.getProperty(PROP_HOME); |
| } |
| } |