CanaryFavicon.java

/*
 *        _____                     __    _     _   _____ _
 *       |   __|___ ___ _ _ ___ ___|  |  |_|___| |_|  _  | |_ _ ___
 *       |__   | -_|  _| | | -_|  _|  |__| |_ -|  _|   __| | | |_ -|
 *       |_____|___|_|  \_/|___|_| |_____|_|___|_| |__|  |_|___|___|
 *
 *  ServerListPlus - http://git.io/slp
 *  Copyright (c) 2014, Minecrell <https://github.com/Minecrell>
 *
 *     This program is free software: you can redistribute it and/or modify
 *     it under the terms of the GNU 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 General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public License
 *     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package net.minecrell.serverlistplus.canary;

import com.google.common.base.Preconditions;
import com.google.common.io.BaseEncoding;

import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;

public final class CanaryFavicon {
    private CanaryFavicon() {}

    public static String create(BufferedImage image) {
        Preconditions.checkArgument(image.getWidth() == 64 && image.getHeight() == 64, "Invalid favicon bounds");

        byte[] buf;
        try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
            ImageIO.write(image, "PNG", out);
            buf = out.toByteArray();
        } catch (IOException e) {
            throw new AssertionError(e);
        }

        return "data:image/png;base64," + BaseEncoding.base64().encode(buf);
    }
}