MainClassTransformer.java

/*
 * Quartz
 * Copyright (c) 2015, Minecrell <https://github.com/Minecrell>
 *
 * Based on Sponge and SpongeAPI, licensed under the MIT License (MIT).
 * Copyright (c) SpongePowered.org <http://www.spongepowered.org>
 * Copyright (c) contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package net.minecrell.quartz.launch.transformers;

import com.google.common.io.ByteStreams;
import net.minecraft.launchwrapper.IClassTransformer;
import net.minecrell.quartz.launch.QuartzTweaker;

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Path;
import java.util.zip.ZipFile;

public class MainClassTransformer implements IClassTransformer {

    private final byte[] mainClass;

    public MainClassTransformer() throws IOException {
        Path serverJar = QuartzTweaker.getServerJar();
        try (ZipFile zip = new ZipFile(serverJar.toFile())) {
            try (InputStream in = zip.getInputStream(zip.getEntry(QuartzTweaker.MAIN_CLASS))) {
                this.mainClass = ByteStreams.toByteArray(in);
            }
        }
    }

    @Override
    public byte[] transform(String name, String transformedName, byte[] basicClass) {
        if (basicClass != null && name.equals(QuartzTweaker.MAIN)) {
            return mainClass;
        } else {
            return basicClass;
        }
    }

}