net.hillsdon.reviki.configuration.DataDirImpl.java Source code

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Here is the source code for net.hillsdon.reviki.configuration.DataDirImpl.java

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/**
 * Copyright 2008 Matthew Hillsdon
 *
 * Licensed 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 net.hillsdon.reviki.configuration;

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

import javax.servlet.ServletContext;

import net.hillsdon.fij.io.Path;

import org.apache.commons.io.FileUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import static org.apache.commons.lang.StringUtils.trimToNull;

public class DataDirImpl implements DataDir {

    private static final Log LOG = LogFactory.getLog(DataDirImpl.class);

    public static final String DATA_DIR_CONTEXT_PARAM = "reviki-data-dir";
    private static final String DEFAULT_CONFIG_DIR_NAME = "reviki-data";
    private static final String SEARCH_INDEX_DIR_NAME = "search-index";
    private static final String CONFIG_FILE_NAME = "reviki.properties";

    private final ServletContext _servletContext;
    private final String _defaultBaseDir;

    public DataDirImpl(final ServletContext servletContext) {
        this(servletContext, System.getProperty("user.home"));
    }

    public DataDirImpl(final ServletContext servletContext, final String defaultBaseDir) {
        _servletContext = servletContext;
        _defaultBaseDir = defaultBaseDir;
    }

    /**
     * @return A configuration location if we can, otherwise null.
     */
    private File getConfigurationLocation() {
        String location = trimToNull(_servletContext.getInitParameter(DATA_DIR_CONTEXT_PARAM));
        if (location == null) {
            try {
                location = Path.join(_defaultBaseDir, DEFAULT_CONFIG_DIR_NAME);
            } catch (SecurityException ex) {
            }
        }
        if (location == null) {
            return null;
        }
        File dir = new File(location);
        try {
            if (!dir.exists()) {
                try {
                    FileUtils.forceMkdir(dir);
                } catch (IOException ex) {
                    LOG.error("Failed to create data area.", ex);
                    return null;
                }
            }
        } catch (SecurityException ex) {
            return null;
        }
        return dir;
    }

    private File getConfigurationFile() {
        File location = getConfigurationLocation();
        if (location != null) {
            File file = new File(location, CONFIG_FILE_NAME);
            return file;
        }
        return null;
    }

    public PersistentStringMap getProperties() {
        return new PropertiesFile(getConfigurationFile());
    }

    public File getSearchIndexDirectory(String identifier) {
        File searchDir = getWritableChildDir(getConfigurationLocation(), SEARCH_INDEX_DIR_NAME);
        return searchDir == null ? null : getWritableChildDir(searchDir, identifier);
    }

    private File getWritableChildDir(final File dir, final String child) {
        File indexDir = new File(dir, child);
        if (!indexDir.exists()) {
            if (!indexDir.mkdir()) {
                return null;
            }
        }
        if (indexDir.isDirectory() && indexDir.canWrite()) {
            return indexDir;
        }
        return null;
    }

}