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 */
033public abstract class FileSystem
034{
035    /** Constant for the default logger. */
036    private static final ConfigurationLogger DEFAULT_LOG = ConfigurationLogger.newDummyLogger();
037
038    /** The Logger */
039    private volatile ConfigurationLogger log;
040
041    /** FileSystem options provider */
042    private volatile FileOptionsProvider optionsProvider;
043
044    /**
045     * Returns the logger used by this FileSystem.
046     *
047     * @return the logger
048     */
049    public ConfigurationLogger getLogger()
050    {
051        final ConfigurationLogger result = log;
052        return (result != null) ? result : DEFAULT_LOG;
053    }
054
055    /**
056     * Allows setting the logger to be used by this FileSystem. This
057     * method makes it possible for clients to exactly control logging behavior.
058     * Per default a logger is set that will ignore all log messages. Derived
059     * classes that want to enable logging should call this method during their
060     * initialization with the logger to be used. Passing in a <b>null</b> argument
061     * disables logging.
062     *
063     * @param log the new logger
064     */
065    public void setLogger(final ConfigurationLogger log)
066    {
067        this.log = log;
068    }
069
070    /**
071     * Set the FileOptionsProvider
072     * @param provider The FileOptionsProvider
073     */
074    public void setFileOptionsProvider(final FileOptionsProvider provider)
075    {
076        this.optionsProvider = provider;
077    }
078
079    public FileOptionsProvider getFileOptionsProvider()
080    {
081        return this.optionsProvider;
082    }
083
084    public abstract InputStream getInputStream(URL url) throws ConfigurationException;
085
086    public abstract OutputStream getOutputStream(URL url) throws ConfigurationException;
087
088    public abstract OutputStream getOutputStream(File file) throws ConfigurationException;
089
090    public abstract String getPath(File file, URL url, String basePath, String fileName);
091
092    public abstract String getBasePath(String path);
093
094    public abstract String getFileName(String path);
095
096    public abstract URL locateFromURL(String basePath, String fileName);
097
098    public abstract URL getURL(String basePath, String fileName) throws MalformedURLException;
099}