com.threerings.cast.bundle.BundleUtil Maven / Gradle / Ivy

Go to download
//
// Nenya library - tools for developing networked games
// Copyright (C) 2002-2012 Three Rings Design, Inc., All Rights Reserved
// https://github.com/threerings/nenya
//
// 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

package com.threerings.cast.bundle;

import java.io.IOException;
import java.io.InputStream;
import java.io.InvalidClassException;
import java.io.ObjectInputStream;

import com.samskivert.io.StreamUtil;

import com.threerings.resource.FileResourceBundle;
import com.threerings.resource.ResourceBundle;

import static com.threerings.cast.Log.log;

/**
 * Utility functions related to creating and manipulating component bundles.
 */
public class BundleUtil
{
    /** The path in the metadata bundle to the serialized action table. */
    public static final String ACTIONS_PATH = "actions.dat";

    /** The path in the metadata bundle to the serialized action tile sets table. */
    public static final String ACTION_SETS_PATH = "action_sets.dat";

    /** The path in the metadata bundle to the serialized component class table. */
    public static final String CLASSES_PATH = "classes.dat";

    /** The path in the component bundle to the serialized component id to class/type mapping. */
    public static final String COMPONENTS_PATH = "components.dat";

    /** The file extension of our action tile images. */
    public static final String IMAGE_EXTENSION = ".png";

    /** The serialized tileset extension for our action tilesets. */
    public static final String TILESET_EXTENSION = ".dat";

    /**
     * Attempts to load an object from the supplied resource bundle with the specified path.
     *
     * @param wipeOnFailure if there is an error reading the object from the bundle and this
     * parameter is true, we will instruct the bundle to delete its underlying jar file before
     * propagating the exception with the expectation that it will be redownloaded and repaired the
     * next time the application is run.
     *
     * @return the unserialized object in question.
     *
     * @exception IOException thrown if an I/O error occurs while reading the object from the
     * bundle.
     */
    public static Object loadObject (ResourceBundle bundle, String path, boolean wipeOnFailure)
        throws IOException, ClassNotFoundException
    {
        InputStream bin = null;
        try {
            bin = bundle.getResource(path);
            if (bin == null) {
                return null;
            }
            return new ObjectInputStream(bin).readObject();

        } catch (InvalidClassException ice) {
            log.warning("Aiya! Serialized object is hosed [bundle=" + bundle +
                        ", element=" + path + ", error=" + ice.getMessage() + "].");
            return null;

        } catch (IOException ioe) {
            log.warning("Error reading resource from bundle [bundle=" + bundle + ", path=" + path +
                        ", wiping?=" + wipeOnFailure + "].");
            if (wipeOnFailure) {
                StreamUtil.close(bin);
                bin = null;
                if (bundle instanceof FileResourceBundle) {
                    ((FileResourceBundle)bundle).wipeBundle(false);
                }
            }
            throw ioe;

        } finally {
            StreamUtil.close(bin);
        }
    }
}