001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.configuration2.io;
018
019import java.io.File;
020import java.io.InputStream;
021import java.io.OutputStream;
022import java.net.MalformedURLException;
023import java.net.URL;
024
025import org.apache.commons.configuration2.ex.ConfigurationException;
026
027/**
028 * Abstract layer to allow various types of file systems.
029 * @since 1.7
030 * @author <a
031 * href="http://commons.apache.org/configuration/team-list.html">Commons Configuration team</a>
032 * @version $Id: FileSystem.java 1735895 2016-03-20 18:40:47Z oheger $
033 */
034public abstract class FileSystem
035{
036    /** Constant for the default logger. */
037    private static final ConfigurationLogger DEFAULT_LOG = ConfigurationLogger.newDummyLogger();
038
039    /** The Logger */
040    private volatile ConfigurationLogger log;
041
042    /** FileSystem options provider */
043    private volatile FileOptionsProvider optionsProvider;
044
045    /**
046     * Returns the logger used by this FileSystem.
047     *
048     * @return the logger
049     */
050    public ConfigurationLogger getLogger()
051    {
052        ConfigurationLogger result = log;
053        return (result != null) ? result : DEFAULT_LOG;
054    }
055
056    /**
057     * Allows setting the logger to be used by this FileSystem. This
058     * method makes it possible for clients to exactly control logging behavior.
059     * Per default a logger is set that will ignore all log messages. Derived
060     * classes that want to enable logging should call this method during their
061     * initialization with the logger to be used. Passing in a <b>null</b> argument
062     * disables logging.
063     *
064     * @param log the new logger
065     */
066    public void setLogger(ConfigurationLogger log)
067    {
068        this.log = log;
069    }
070
071    /**
072     * Set the FileOptionsProvider
073     * @param provider The FileOptionsProvider
074     */
075    public void setFileOptionsProvider(FileOptionsProvider provider)
076    {
077        this.optionsProvider = provider;
078    }
079
080    public FileOptionsProvider getFileOptionsProvider()
081    {
082        return this.optionsProvider;
083    }
084
085    public abstract InputStream getInputStream(URL url) throws ConfigurationException;
086
087    public abstract OutputStream getOutputStream(URL url) throws ConfigurationException;
088
089    public abstract OutputStream getOutputStream(File file) throws ConfigurationException;
090
091    public abstract String getPath(File file, URL url, String basePath, String fileName);
092
093    public abstract String getBasePath(String path);
094
095    public abstract String getFileName(String path);
096
097    public abstract URL locateFromURL(String basePath, String fileName);
098
099    public abstract URL getURL(String basePath, String fileName) throws MalformedURLException;
100}