org.unitime.timetable.solver.ui.TimetableInfoUtil.java Source code

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Here is the source code for org.unitime.timetable.solver.ui.TimetableInfoUtil.java

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/*
 * Licensed to The Apereo Foundation under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for
 * additional information regarding copyright ownership.
 *
 * The Apereo Foundation licenses this file to you 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 org.unitime.timetable.solver.ui;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
import org.unitime.timetable.ApplicationProperties;
import org.unitime.timetable.solver.jgroups.CourseSolverContainer;
import org.unitime.timetable.solver.jgroups.SolverServer;
import org.unitime.timetable.solver.jgroups.SolverServerImplementation;

/**
 * @author Tomas Muller
 */
public class TimetableInfoUtil implements TimetableInfoFileProxy {
    private static Log sLog = LogFactory.getLog(TimetableInfoUtil.class);
    private static TimetableInfoUtil sInstance = new TimetableInfoUtil();

    private TimetableInfoUtil() {
    }

    public static TimetableInfoUtil getLocalInstance() {
        return sInstance;
    }

    public static TimetableInfoFileProxy getInstance() {
        // Create the cluster instance
        SolverServer server = SolverServerImplementation.getInstance();
        if (server != null && server.getCourseSolverContainer() != null)
            return ((CourseSolverContainer) server.getCourseSolverContainer()).getFileProxy();

        // Fall back to local instance
        return getLocalInstance();
    }

    public boolean saveToFile(String name, TimetableInfo info) {
        FileOutputStream out = null;
        try {
            File file = new File(ApplicationProperties.getBlobFolder(), name);
            file.getParentFile().mkdirs();
            out = new FileOutputStream(file);
            XMLWriter writer = new XMLWriter(new GZIPOutputStream(out), OutputFormat.createCompactFormat());
            Document document = DocumentHelper.createDocument();
            Element root = document.addElement(info.getClass().getName());
            info.save(root);
            writer.write(document);
            writer.flush();
            writer.close();
            out.flush();
            out.close();
            out = null;
            sLog.info("Saved info " + name + " as " + file + " (" + file.length() + " bytes)");
            return true;
        } catch (Exception e) {
            sLog.warn("Failed to save info " + name + ": " + e.getMessage(), e);
            return false;
        } finally {
            try {
                if (out != null)
                    out.close();
            } catch (IOException e) {
            }
        }
    }

    public TimetableInfo loadFromFile(String name) {
        try {
            File file = new File(ApplicationProperties.getBlobFolder(), name);
            if (!file.exists())
                return null;
            sLog.info("Loading info " + name + " from " + file + " (" + file.length() + " bytes)");
            Document document = null;
            GZIPInputStream gzipInput = null;
            try {
                gzipInput = new GZIPInputStream(new FileInputStream(file));
                document = (new SAXReader()).read(gzipInput);
            } finally {
                if (gzipInput != null)
                    gzipInput.close();
            }
            Element root = document.getRootElement();
            String infoClassName = root.getName();
            Class infoClass = Class.forName(infoClassName);
            TimetableInfo info = (TimetableInfo) infoClass.getConstructor(new Class[] {})
                    .newInstance(new Object[] {});
            info.load(root);
            return info;
        } catch (Exception e) {
            sLog.warn("Failed to load info " + name + ": " + e.getMessage(), e);
            return null;
        }
    }

    public boolean deleteFile(String name) {
        try {
            File file = new File(ApplicationProperties.getBlobFolder(), name);
            if (file.exists()) {
                sLog.info("Deleting info " + name + " as " + file + " (" + file.length() + " bytes)");
                file.delete();
                return true;
            }
            return false;
        } catch (Exception e) {
            sLog.warn("Failed to delete info " + name + ": " + e.getMessage(), e);
            return false;
        }
    }
}