There are many development jar packages for Java generation of QR codes. For example, zxing is developed by Google. Here I use zxing's development package to implement it. In many projects, we need to dynamically generate QR codes to provide them to users, so that more people can experience their applications well through QR codes.
The code is posted below, and it has been tested and you can copy the code directly to use:
Finally achieved results:
java generates QR code
The code is as follows:
import java.awt.Color;import java.awt.Graphics2D;import java.awt.Image;import java.awt.geom.AffineTransform;import java.awt.image.AffineTransformOp;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.util.HashMap;import java.util.Map;import javax.imageio.ImageIO; import com.google.zxing.BarcodeFormat;import com.google.zxing.EncodeHintType;import com.google.zxing.MultiFormatWriter;import com.google.zxing.WriterException;import com.google.zxing.common.BitMatrix;import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel; public class MatrixToImageWriter { private static final int IMAGE_WIDTH = 100; private static final int IMAGE_HEIGHT = 100; private static final int IMAGE_HALF_WIDTH = IMAGE_WIDTH / 2; private static final int FRAME_WIDTH = 2; private static MultiFormatWriter mutiWriter = new MultiFormatWriter(); public static void encode(String content, int width, int height, String srcImagePath, String destImagePath) { try { ImageIO.write(genBarcode(content, width, height, srcImagePath), "jpg", new File(destImagePath)); } catch (IOException e) { e.printStackTrace(); } catch (WriterException e) { e.printStackTrace(); } } private static BufferedImage genBarcode(String content, int width, int height, String srcImagePath) throws WriterException, IOException { BufferedImage scaleImage = scale(srcImagePath, IMAGE_WIDTH, IMAGE_HEIGHT, true); int[][] srcPixels = new int[IMAGE_WIDTH][IMAGE_HEIGHT]; for (int i = 0; i < scaleImage.getWidth(); i++) { for (int j = 0; j < scaleImage.getHeight(); j++) { srcPixels[i][j] = scaleImage.getRGB(i, j); } } Map<EncodeHintType, Object> hint = new HashMap<EncodeHintType, Object>(); hint.put(EncodeHintType.CHARACTER_SET, "utf-8"); hint.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); // Generate QR code BitMatrix matrix = mutiWriter.encode(content, BarcodeFormat.QR_CODE, width, height, hint); // Convert the two-dimensional matrix into a one-dimensional pixel array int halfW = matrix.getWidth() / 2; int halfH = matrix.getHeight() / 2; int[] pixels = new int[width * height]; for (int y = 0; y < matrix.getHeight(); y++) { for (int x = 0; x < matrix.getWidth(); x++) { // The color in the upper left corner, adjust the color range and color according to your needs if (x > 0 && x < 170 && y > 0 && y < 170) { Color color = new Color(231, 144, 56); int colorInt = color.getRGB(); pixels[y * width + x] = matrix.get(x, y) ? colorInt : 16777215; } // Read the picture else if (x > halfW - IMAGE_HALF_WIDTH && x < halfW + IMAGE_HALF_WIDTH && y > halfH - IMAGE_HALF_WIDTH && y < halfH + IMAGE_HALF_WIDTH) { pixels[y * width + x] = srcPixels[x - halfW + IMAGE_HALF_WIDTH][y - halfH + IMAGE_HALF_WIDTH]; } else if ((x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH && x < halfW - IMAGE_HALF_WIDTH + FRAME_WIDTH && y > halfH - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH + IMAGE_HALF_WIDTH + FRAME_WIDTH) || (x > halfW + IMAGE_HALF_WIDTH - FRAME_WIDTH && x < halfW + IMAGE_HALF_WIDTH + FRAME_WIDTH && y > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH + IMAGE_HALF_WIDTH + FRAME_WIDTH) || (x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH && x < halfW + IMAGE_HALF_WIDTH + FRAME_WIDTH && y > halfH - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH - IMAGE_HALF_WIDTH + FRAME_WIDTH) || (x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH - IMAGE_HALF_WIDTH + FRAME_WIDTH) || (x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH && y x < halfW + IMAGE_HALF_WIDTH + FRAME_WIDTH && y > halfH + IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH + IMAGE_HALF_WIDTH + FRAME_WIDTH)) { pixels[y * width + x] = 0xffffffff; // Form a border around the picture} else { // QR code color int num1 = (int) (50 - (50.0 - 13.0) / matrix.getHeight() * (y + 1)); int num2 = (int) (165 - (165.0 - 72.0) / matrix.getHeight() * (y + 1)); int num3 = (int) (162 - (162.0 - 107.0) / matrix.getHeight() * (y + 1)); Color color = new Color(num1, num2, num3); int colorInt = color.getRGB(); // Here you can modify the QR code color, and you can formulate the QR code and background colors respectively; pixels[y * width + x] = matrix.get(x, y) ? colorInt : 16777215; // 0x00000:0xffffff } } } BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); image.getRaster().setDataElements(0, 0, width, height, pixels); return image; } private static BufferedImage scale(String srcImageFile, int height, int width, boolean hasFiller) throws IOException { double ratio = 0.0; // Scale File file = new File(srcImageFile); BufferedImage srcImage = ImageIO.read(file); Image destImage = srcImage.getScaledInstance(width, height, BufferedImage.SCALE_SMOOTH); // Calculate the scale if ((srcImage.getHeight() > height) || (srcImage.getWidth() > width)) { if (srcImage.getHeight() > srcImage.getWidth()) { ratio = (new Integer(height)).doubleValue() / srcImage.getHeight(); } else { ratio = (new Integer(width)).doubleValue() / srcImage.getWidth(); } AffineTransformOp op = new AffineTransformOp( AffineTransform.getScaleInstance(ratio, ratio), null); destImage = op.filter(srcImage, null); } if (hasFiller) { // Filling BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics2D graphic = image.createGraphics(); graphic.setColor(Color.white); graphic.fillRect(0, 0, width, height); if (width == destImage.getWidth(null)) graphic.drawImage(destImage, 0, (height - destImage.getHeight(null)) / 2, destImage.getWidth(null), destImage.getHeight(null), Color.white, null); else graphic.drawImage(destImage, (width - destImage.getWidth(null)) / 2, 0, destImage.getWidth(null), destImage.getHeight(null), Color.white, null); graphic.dispose(); destImage = image; } return (BufferedImage) destImage; } public static void main(String[] args) throws UnsupportedEncodingException { // In turn, content (not supported in Chinese), width, length, middle icon path, storage path MatrixToImageWriter.encode("http://www.baidu.com/", 512, 512, "D://logo.png", "D://2013-01.jpg"); }}You can refer to the topic: java QR code for learning
The above is all about this article, helping you design your own QR code.