QRServlet.java

/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2012, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This 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 software 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 software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.keycloak.forms;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.jboss.resteasy.logging.Logger;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;

/**
 * @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
 */
@WebServlet(urlPatterns = "/forms/qrcode")
public class QRServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    private static final Logger log = Logger.getLogger(QRServlet.class);

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String[] size = req.getParameter("size").split("x");
        int width = Integer.parseInt(size[0]);
        int height = Integer.parseInt(size[1]);

        String contents = req.getParameter("contents");

        try {
            QRCodeWriter writer = new QRCodeWriter();

            BitMatrix bitMatrix = writer.encode(contents, BarcodeFormat.QR_CODE, width, height);

            MatrixToImageWriter.writeToStream(bitMatrix, "png", resp.getOutputStream());
            resp.setContentType("image/png");
        } catch (Exception e) {
            log.warn("Failed to generate qr code", e);
            resp.sendError(500);
        }
    }

}