org.primefaces.application.resource.QRCodeHandler Maven / Gradle / Ivy
/*
* The MIT License
*
* Copyright (c) 2009-2023 PrimeTek Informatics
*
* 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 org.primefaces.application.resource;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Map;
import java.util.Objects;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.imageio.ImageIO;
import org.primefaces.util.Constants;
import org.primefaces.util.LangUtils;
import io.nayuki.qrcodegen.QrCode;
import io.nayuki.qrcodegen.QrCode.Ecc;
public class QRCodeHandler extends BaseDynamicContentHandler {
@Override
public void handle(FacesContext context) throws IOException {
Map params = context.getExternalContext().getRequestParameterMap();
ExternalContext externalContext = context.getExternalContext();
String sessionKey = params.get(Constants.DYNAMIC_CONTENT_PARAM);
Map session = externalContext.getSessionMap();
Map barcodeMapping = (Map) session.get(Constants.BARCODE_MAPPING);
if (barcodeMapping == null) {
return;
}
String value = barcodeMapping.get(sessionKey);
if (value == null) {
return;
}
boolean cache = Boolean.parseBoolean(params.get(Constants.DYNAMIC_CONTENT_CACHE_PARAM));
QrCode qrCode = QrCode.encodeText(value, getErrorCorrection(params.get("qrec")));
if ("png".equals(params.get("fmt"))) {
externalContext.setResponseContentType("image/png");
ImageIO.write(toImage(qrCode, 12, 0), "png", externalContext.getResponseOutputStream());
}
else {
externalContext.setResponseContentType("image/svg+xml");
externalContext.getResponseOutputWriter().write(toSvgString(qrCode, 0, "#FFFFFF", "#000000"));
}
handleCache(externalContext, cache);
externalContext.setResponseStatus(200);
externalContext.responseFlushBuffer();
context.responseComplete();
}
protected Ecc getErrorCorrection(final String value) {
switch (LangUtils.isNotBlank(value) ? value : Constants.EMPTY_STRING) {
case "M":
return Ecc.MEDIUM;
case "Q":
return Ecc.QUARTILE;
case "H":
return Ecc.HIGH;
default:
return Ecc.LOW;
}
}
protected BufferedImage toImage(QrCode qr, int scale, int border) {
return toImage(qr, scale, border, 0xFFFFFF, 0x000000);
}
/**
* Returns a raster image depicting the specified QR Code, with
* the specified module scale, border modules, and module colors.
* For example, scale=10 and border=4 means to pad the QR Code with 4 light border
* modules on all four sides, and use 10×10 pixels to represent each module.
* @param qr the QR Code to render (not {@code null})
* @param scale the side length (measured in pixels, must be positive) of each module
* @param border the number of border modules to add, which must be non-negative
* @param lightColor the color to use for light modules, in 0xRRGGBB format
* @param darkColor the color to use for dark modules, in 0xRRGGBB format
* @return a new image representing the QR Code, with padding and scaling
* @throws NullPointerException if the QR Code is {@code null}
* @throws IllegalArgumentException if the scale or border is out of range, or if
* {scale, border, size} cause the image dimensions to exceed Integer.MAX_VALUE
*/
protected BufferedImage toImage(QrCode qr, int scale, int border, int lightColor, int darkColor) {
Objects.requireNonNull(qr);
if (scale <= 0 || border < 0) {
throw new IllegalArgumentException("Value out of range");
}
if (border > Integer.MAX_VALUE / 2 || qr.size + border * 2L > Integer.MAX_VALUE / scale) {
throw new IllegalArgumentException("Scale or border too large");
}
BufferedImage result = new BufferedImage((qr.size + border * 2) * scale, (qr.size + border * 2) * scale, BufferedImage.TYPE_INT_RGB);
for (int y = 0; y < result.getHeight(); y++) {
for (int x = 0; x < result.getWidth(); x++) {
boolean color = qr.getModule(x / scale - border, y / scale - border);
result.setRGB(x, y, color ? darkColor : lightColor);
}
}
return result;
}
/**
* Returns a string of SVG code for an image depicting the specified QR Code, with the specified
* number of border modules. The string always uses Unix newlines (\n), regardless of the platform.
* @param qr the QR Code to render (not {@code null})
* @param border the number of border modules to add, which must be non-negative
* @param lightColor the color to use for light modules, in any format supported by CSS, not {@code null}
* @param darkColor the color to use for dark modules, in any format supported by CSS, not {@code null}
* @return a string representing the QR Code as an SVG XML document
* @throws NullPointerException if any object is {@code null}
* @throws IllegalArgumentException if the border is negative
*/
protected String toSvgString(QrCode qr, int border, String lightColor, String darkColor) {
Objects.requireNonNull(qr);
Objects.requireNonNull(lightColor);
Objects.requireNonNull(darkColor);
if (border < 0) {
throw new IllegalArgumentException("Border must be non-negative");
}
long brd = border;
StringBuilder sb = new StringBuilder()
.append("\n")
.append("\n")
.append(String.format("\n").toString();
}
}