org.languagetool.gui.LocalStorage.java Source code

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Here is the source code for org.languagetool.gui.LocalStorage.java

Source

/* LanguageTool, a natural language style checker 
 * Copyright (C) 2016 Daniel Naber (http://www.danielnaber.de)
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
 * USA
 */
package org.languagetool.gui;

import java.beans.XMLDecoder;
import java.beans.XMLEncoder;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.SystemUtils;

/**
 * Helper class to store configuration
 *
 * @author Panagiotis Minos
 * @since 3.4
 */
class LocalStorage {

    private static final String VENDOR_ID = "languagetool.org";
    private static final String APPLICATION_ID = "LanguageTool";

    private final File directory;

    LocalStorage() {
        String userHome = null;
        try {
            userHome = System.getProperty("user.home");
        } catch (SecurityException ex) {
        }
        if (userHome == null) {
            directory = null;
        } else if (SystemUtils.IS_OS_WINDOWS) {
            File appDataDir = null;
            try {
                String appData = System.getenv("APPDATA");
                if (!StringUtils.isEmpty(appData)) {
                    appDataDir = new File(appData);
                }
            } catch (SecurityException ex) {
            }
            if (appDataDir != null && appDataDir.isDirectory()) {
                String path = VENDOR_ID + "\\" + APPLICATION_ID + "\\";
                directory = new File(appDataDir, path);
            } else {
                String path = "Application Data\\" + VENDOR_ID + "\\" + APPLICATION_ID + "\\";
                directory = new File(userHome, path);
            }
        } else if (SystemUtils.IS_OS_LINUX) {
            File appDataDir = null;
            try {
                String xdgConfigHome = System.getenv("XDG_CONFIG_HOME");
                if (!StringUtils.isEmpty(xdgConfigHome)) {
                    appDataDir = new File(xdgConfigHome);
                    if (!appDataDir.isAbsolute()) {
                        //https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
                        //All paths set in these environment variables must be absolute.
                        //If an implementation encounters a relative path in any of these
                        //variables it should consider the path invalid and ignore it.
                        appDataDir = null;
                    }
                }
            } catch (SecurityException ex) {
            }
            if (appDataDir != null && appDataDir.isDirectory()) {
                String path = APPLICATION_ID + "/";
                directory = new File(appDataDir, path);
            } else {
                String path = ".config/" + APPLICATION_ID + "/";
                directory = new File(userHome, path);
            }
        } else if (SystemUtils.IS_OS_MAC_OSX) {
            String path = "Library/Application Support/" + APPLICATION_ID + "/";
            directory = new File(userHome, path);
        } else {
            String path = "." + APPLICATION_ID + "/";
            directory = new File(userHome, path);
        }
        if (directory != null && !directory.exists()) {
            directory.mkdirs();
        }
    }

    void saveProperty(String name, Object obj) {
        if (directory == null) {
            return;
        }
        synchronized (directory) {
            try (XMLEncoder encoder = new XMLEncoder(
                    new BufferedOutputStream(new FileOutputStream(new File(directory, name))))) {
                encoder.writeObject(obj);
            } catch (FileNotFoundException ex) {
                Tools.showError(ex);
            }
        }
    }

    <T> T loadProperty(String name, Class<T> clazz) {
        if (directory == null) {
            return null;
        }
        synchronized (directory) {
            try (XMLDecoder decoder = new XMLDecoder(
                    new BufferedInputStream(new FileInputStream(new File(directory, name))))) {
                try {
                    return clazz.cast(decoder.readObject());
                } catch (ClassCastException ex) {
                    Tools.showError(ex);
                    return null;
                } catch (Exception ex) {
                    //probably user messed up with files
                    Tools.showError(ex);
                    return null;
                }
            } catch (FileNotFoundException ex) {
                //ignore, we have not saved yet a property with this name
            }
        }
        return null;
    }

}