    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 */
    031public abstract class FileSystem
    032{
    033    /** Constant for the default logger. */
    034    private static final ConfigurationLogger DEFAULT_LOG = ConfigurationLogger.newDummyLogger();
    035
    036    /** The Logger */
    037    private volatile ConfigurationLogger log;
    038
    039    /** FileSystem options provider */
    040    private volatile FileOptionsProvider optionsProvider;
    041
    042    /**
    043     * Returns the logger used by this FileSystem.
    044     *
    045     * @return the logger
    046     */
    047    public ConfigurationLogger getLogger()
    048    {
    049        final ConfigurationLogger result = log;
    050        return result != null ? result : DEFAULT_LOG;
    051    }
    052
    053    /**
    054     * Allows setting the logger to be used by this FileSystem. This
    055     * method makes it possible for clients to exactly control logging behavior.
    056     * Per default a logger is set that will ignore all log messages. Derived
    057     * classes that want to enable logging should call this method during their
    058     * initialization with the logger to be used. Passing in a <b>null</b> argument
    059     * disables logging.
    060     *
    061     * @param log the new logger
    062     */
    063    public void setLogger(final ConfigurationLogger log)
    064    {
    065        this.log = log;
    066    }
    067
    068    /**
    069     * Set the FileOptionsProvider
    070     * @param provider The FileOptionsProvider
    071     */
    072    public void setFileOptionsProvider(final FileOptionsProvider provider)
    073    {
    074        this.optionsProvider = provider;
    075    }
    076
    077    public FileOptionsProvider getFileOptionsProvider()
    078    {
    079        return this.optionsProvider;
    080    }
    081
    082    public abstract InputStream getInputStream(URL url) throws ConfigurationException;
    083
    084    public abstract OutputStream getOutputStream(URL url) throws ConfigurationException;
    085
    086    public abstract OutputStream getOutputStream(File file) throws ConfigurationException;
    087
    088    public abstract String getPath(File file, URL url, String basePath, String fileName);
    089
    090    public abstract String getBasePath(String path);
    091
    092    public abstract String getFileName(String path);
    093
    094    public abstract URL locateFromURL(String basePath, String fileName);
    095
    096    public abstract URL getURL(String basePath, String fileName) throws MalformedURLException;
    097}