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

Go to download
Show more of this group Show more artifacts with this name
Show all versions of nenya Show documentation
Facilities for making networked multiplayer games.
The newest version!
//
// 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);
        }
    }
}