<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>core</artifactId>
<version>3.3.3</version>
</dependency>
import com.google.zxing.LuminanceSource;
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
public class BufferedImageLuminanceSource extends LuminanceSource {
private BufferedImage image = null;
private int left= 0;;
private int top= 0;;
public BufferedImageLuminanceSource(BufferedImage image) {
this(image, 0, 0, image.getWidth(), image.getHeight());
}
public BufferedImageLuminanceSource(BufferedImage image, int left, int top, int width, int height) {
super(width, height);
int sourceWidth = image.getWidth();
int sourceHeight = image.getHeight();
if (left + width > sourceWidth || top + height > sourceHeight) {
throw new IllegalArgumentException("Crop rectangle does not fit within image data.");
}
for (int y = top; y < top + height; y++) {
for (int x = left; x < left + width; x++) {
if ((image.getRGB(x, y) & 0xFF000000) == 0) {
image.setRGB(x, y, 0xFFFFFFFF); // = white
}
}
}
this.image = new BufferedImage(sourceWidth, sourceHeight, BufferedImage.TYPE_BYTE_GRAY);
this.image.getGraphics().drawImage(image, 0, 0, null);
this.left = left;
this.top = top;
}
protected BufferedImageLuminanceSource(int width, int height) {
super(width, height);
}
@Override
public byte[] getRow(int y, byte[] row) {
if (y < 0 || y >= getHeight()) {
throw new IllegalArgumentException("Requested row is outside the image: " + y);
}
int width = getWidth();
if (row == null || row.length < width) {
row = new byte[width];
}
image.getRaster().getDataElements(left, top + y, width, 1, row);
return row;
}
@Override
public byte[] getMatrix() {
int width = getWidth();
int height = getHeight();
int area = width * height;
byte[] matrix = new byte[area];
image.getRaster().getDataElements(left, top, width, height, matrix);
return matrix;
}
@Override
public boolean isCropSupported() {
return true;
}
@Override
public LuminanceSource crop(int left, int top, int width, int height) {
return new BufferedImageLuminanceSource(image, this.left + left, this.top + top, width, height);
}
@Override
public boolean isRotateSupported() {
return true;
}
@Override
public LuminanceSource rotateCounterClockwise() {
int sourceWidth = image.getWidth();
int sourceHeight = image.getHeight();
AffineTransform transform = new AffineTransform(0.0, -1.0, 1.0, 0.0, 0.0, sourceWidth);
BufferedImage rotatedImage = new BufferedImage(sourceHeight, sourceWidth, BufferedImage.TYPE_BYTE_GRAY);
Graphics2D g = rotatedImage.createGraphics();
g.drawImage(image, transform, null);
g.dispose();
int width = getWidth();
return new BufferedImageLuminanceSource(rotatedImage, top, sourceWidth - (left + width), getHeight(), width);
}
}
import com.google.zxing.*;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.util.Hashtable;
public class QrCodeUtils {
//编码
private static final String CHARSET = "utf-8";
private static final String FORMAT_NAME = "PNG";
// 二维码尺寸
private static final int QRCODE_SIZE = 300;
// LOGO宽度
private static final int WIDTH = 60;
// LOGO高度
private static final int HEIGHT = 60;
/**
* 生成二维码
* @param content 扫描成功的内容
* @param imgPath 生成二维码的路径
* @param needCompress 是否需要压缩
* @return
* @throws Exception
*/
private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception {
//等同于hashmap,hashtable是线程安全的
Hashtable hints = new Hashtable();
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
hints.put(EncodeHintType.MARGIN, 1);
BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);
int width = bitMatrix.getWidth();
int height = bitMatrix.getHeight();
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
}
}
if (imgPath == null || "".equals(imgPath)) {
return image;
}
// 插入图片
QrCodeUtils.insertImage(image, imgPath, needCompress);
return image;
}
/**
* 插入图片
* @param source
* @param imgPath 嵌入二维码的图片路径
* @param needCompress 是否需要压缩
* @throws Exception
*/
private static void insertImage(BufferedImage source, String imgPath, boolean needCompress) throws Exception {
File file = new File(imgPath);
if (!file.exists()) {
return;
}
Image src = ImageIO.read(new File(imgPath));
int width = src.getWidth(null);
int height = src.getHeight(null);
//压缩LOGO
if (needCompress) {
if (width > WIDTH) {
width = WIDTH;
}
if (height > HEIGHT) {
height = HEIGHT;
}
Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);
BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g = tag.getGraphics();
// 绘制缩小后的图
g.drawImage(image, 0, 0, null);
g.dispose();
src = image;
}
// 插入LOGO
Graphics2D graph = source.createGraphics();
int x = (QRCODE_SIZE - width) / 2;
int y = (QRCODE_SIZE - height) / 2;
graph.drawImage(src, x, y, width, height, null);
Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);
graph.setStroke(new BasicStroke(3f));
graph.draw(shape);
graph.dispose();
}
/**
* 生成二维码
* @param content 扫描成功的内容
* @param imgPath 嵌入二维码的图片路径
* @param destPath 生成之后二维码路径
* @param needCompress 是否需要压缩
* @throws Exception
*/
public static void encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception {
BufferedImage image = QrCodeUtils.createImage(content, imgPath, needCompress);
mkdirs(destPath);
ImageIO.write(image, FORMAT_NAME, new File(destPath));
}
/**
* 生成二维码
* @param content 扫描成功的内容
* @param imgPath 嵌入二维码的图片路径
* @param needCompress 是否需要压缩
* @return
* @throws Exception
*/
public static BufferedImage encode(String content, String imgPath, boolean needCompress) throws Exception {
BufferedImage image = QrCodeUtils.createImage(content, imgPath, needCompress);
return image;
}
/**
*
* @param content 扫描成功的内容
* @param imgPath 嵌入二维码的图片路径
* @param destPath 生成之后二维码路径
* @throws Exception
*/
public static void encode(String content, String imgPath, String destPath) throws Exception {
QrCodeUtils.encode(content, imgPath, destPath, false);
}
/**
*
* @param content 扫描成功的内容
* @param destPath 生成之后二维码路径
* @throws Exception
*/
public static void encode(String content, String destPath) throws Exception {
QrCodeUtils.encode(content, null, destPath, false);
}
/**
*
* @param content 扫描成功的内容
* @param imgPath 嵌入二维码的图片路径
* @param output 输出流
* @param needCompress 是否需要压缩
* @throws Exception
*/
public static void encode(String content, String imgPath, OutputStream output, boolean needCompress)
throws Exception {
BufferedImage image = QrCodeUtils.createImage(content, imgPath, needCompress);
ImageIO.write(image, FORMAT_NAME, output);
}
/**
*
* @param content 扫描成功的内容
* @param output 输出流
* @throws Exception
*/
public static void encode(String content, OutputStream output) throws Exception {
QrCodeUtils.encode(content, null, output, false);
}
/**
* 对二维码进行解码
* @param file 二维码路径+二维码名称
* @return
* @throws Exception
*/
public static String decode(File file) throws Exception {
BufferedImage image;
image = ImageIO.read(file);
if (image == null) {
return null;
}
BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Result result;
Hashtable hints = new Hashtable();
hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
result = new MultiFormatReader().decode(bitmap, hints);
String resultStr = result.getText();
return resultStr;
}
/**
* 对二维码进行解码
* @param path 二维码路径+二维码名称
* @return
* @throws Exception
*/
public static String decode(String path) throws Exception {
return QrCodeUtils.decode(new File(path));
}
/**
* 创建文件夹
* @param destPath 文件夹路径
*/
public static void mkdirs(String destPath) {
File file = new File(destPath);
// 当文件夹不存在时，mkdirs会自动创建多层目录，区别于mkdir．(mkdir如果父目录不存在则会抛出异常)
if (!file.exists() && !file.isDirectory()) { file.mkdirs();}
}
}
import cn.wang.blog.utils.QrCodeUtils;
public class QrCodeTest {
public static void main(String[] args) throws Exception {
// 存放在二维码中的内容
String text = "https://www.baidu.com";
// 嵌入二维码的图片路径
String imgPath = "C:/Users/Emmonite/Pictures/v2-f2a5ccbf16a8cca24d300423b1dca971_hd.jpg";
// 生成的二维码的路径及名称
String destPath = "C:/Users/Emmonite/Pictures/jam.png";
//生成二维码
QrCodeUtils.encode(text,imgPath,destPath,true);
// 解析二维码
String str = QrCodeUtils.decode(destPath);
// 打印出解析出的内容
System.out.println(str);
}
}
原文：https://www.cnblogs.com/erosion/p/13201168.html