/*
* WorldEdit, a Minecraft world manipulation toolkit
* Copyright (C) sk89q <http://www.sk89q.com>
* Copyright (C) WorldEdit team and contributors
*
* This program 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 3 of the License, or
* (at your option) any later version.
*
* This program 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 program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.sk89q.worldedit.session.storage;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonIOException;
import com.google.gson.JsonParseException;
import com.sk89q.worldedit.LocalSession;
import com.sk89q.worldedit.util.gson.GsonUtil;
import com.sk89q.worldedit.util.io.Closer;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.UUID;
import java.util.logging.Level;
import java.util.logging.Logger;
import static com.google.common.base.Preconditions.checkNotNull;
/**
* Stores sessions as JSON files in a directory.
*
* <p>Currently, this implementation doesn't handle thread safety very well.</p>
*/
public class JsonFileSessionStore implements SessionStore {
private static final Logger log = Logger.getLogger(JsonFileSessionStore.class.getCanonicalName());
private final Gson gson;
private final File dir;
/**
* Create a new session store.
*
* @param dir the directory
*/
public JsonFileSessionStore(File dir) {
checkNotNull(dir);
if (!dir.isDirectory()) {
if (!dir.mkdirs()) {
log.log(Level.WARNING, "Failed to create directory '" + dir.getPath() + "' for sessions");
}
}
this.dir = dir;
GsonBuilder builder = GsonUtil.createBuilder();
gson = builder.create();
}
/**
* Get the path for the given UUID.
*
* @param id the ID
* @return the file
*/
private File getPath(UUID id) {
checkNotNull(id);
return new File(dir, id + ".json");
}
@Override
public LocalSession load(UUID id) throws IOException {
File file = getPath(id);
Closer closer = Closer.create();
try {
FileReader fr = closer.register(new FileReader(file));
BufferedReader br = closer.register(new BufferedReader(fr));
return gson.fromJson(br, LocalSession.class);
} catch (JsonParseException e) {
throw new IOException(e);
} catch (FileNotFoundException e) {
return new LocalSession();
} finally {
try {
closer.close();
} catch (IOException ignored) {
}
}
}
@Override
public void save(UUID id, LocalSession session) throws IOException {
File finalFile = getPath(id);
File tempFile = new File(finalFile.getParentFile(), finalFile.getName() + ".tmp");
Closer closer = Closer.create();
try {
FileWriter fr = closer.register(new FileWriter(tempFile));
BufferedWriter bw = closer.register(new BufferedWriter(fr));
gson.toJson(session, bw);
} catch (JsonIOException e) {
throw new IOException(e);
} finally {
try {
closer.close();
} catch (IOException ignored) {
}
}
if (finalFile.exists()) {
if (!finalFile.delete()) {
log.log(Level.WARNING, "Failed to delete " + finalFile.getPath() + " so the .tmp file can replace it");
}
}
if (!tempFile.renameTo(finalFile)) {
log.log(Level.WARNING, "Failed to rename temporary session file to " + finalFile.getPath());
}
}
}