Java解析二维码的工具

Java使用zxing可以生成二维码，该工具类作为 java 项目使用 google 开源项目 zxing 生成和解析二维码。代码实现。

依赖：

使用zxing需要导入jar包，这里使用maven依赖

<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>core</artifactId>
<version>3.3.0</version>
</dependency>

代码：

package com.dmeo.utils;
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.URL;
import java.net.URLDecoder;
import java.util.Hashtable;
import java.util.Random;
import javax.imageio.ImageIO;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
/**
*@description: Use Google open source project zxing Generating and parsing QR codes
*2018 year 4 month 11 Japan Afternoon 2:29:41
*/
public class QRCodeUtil{
private static final String CHARSET = "utf-8";
private static final String FORMAT_NAME = "JPG";
// QR code size
private static final int QRCODE_SIZE = 300;
// LOGO Width
private static final int WIDTH = 60;
// LOGO Height
private static final int HEIGHT = 60;
/********************* Two dimensional code generation method and overload method *********************/
/**
* Generate qr code ( Embedded LOGO)
* @param content
* Content
* @param imgPath
* LOGO Address
* @param destPath
* Storage directory
* @param needCompress
* Is it compressed? LOGO
* @throws Exception
*/
public static String encode(String content, String imgPath, String destPath,
boolean needCompress) throws Exception {
BufferedImage image = createImage(content, imgPath,
needCompress);
mkdirs(destPath);
String file = new Random().nextInt(99999999)+".jpg";
ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));
return file;
}
/**
* Generate qr code ( Embedded LOGO)
* @param content
* Content
* @param imgPath
* LOGO Address
* @param destPath
* Storage address
* @throws Exception
*/
public static String encode(String content, String imgPath, String destPath)
throws Exception {
String fileName = encode(content, imgPath, destPath, true);
return fileName;
}
/**
* Generate qr code ( It doesn't contain LOGO)
* @param content
* Content
* @param destPath
* Storage address
* @param needCompress
* Is it compressed?
* @throws Exception
*/
public static void encode(String content, String destPath,
boolean needCompress) throws Exception {
encode(content, null, destPath, needCompress);
}
/**
* Generate qr code ( It doesn't contain LOGO, And do not compress the picture )
* @param content
* Content
* @param destPath
* Storage address
* @throws Exception
*/
public static void encode(String content, String destPath) throws Exception {
encode(content, null, destPath, false);
}
/**
* Generate qr code ( Embedded LOGO)
* @param content
* Content
* @param imgPath
* LOGO Address
* @param output
* Output stream
* @param needCompress
* Is it compressed? LOGO
* @throws Exception
*/
public static void encode(String content, String imgPath,
OutputStream output, boolean needCompress) throws Exception {
BufferedImage image = createImage(content, imgPath,
needCompress);
ImageIO.write(image, FORMAT_NAME, output);
}
/**
* Generate qr code
* @param content
* Content
* @param output
* Output stream
* @throws Exception
*/
public static void encode(String content, OutputStream output)
throws Exception {
encode(content, null, output, false);
}
/********************* Two dimensional code analysis method and overload *********************/
/**
* Analysis of QR code
* @param file
* QR code picture
* @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<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
result = new MultiFormatReader().decode(bitmap, hints);
String resultStr = result.getText();
return resultStr;
}
/**
* Analysis of QR code
* @param path
* QR code image address
* @return
* @throws Exception
*/
public static String decode(String path) throws Exception {
return decode(new File(path));
}
/************************ In the use of ecode Method is a static method called when creating QR code **********************/
private static BufferedImage createImage(String content, String imgPath,
boolean needCompress) throws Exception {
Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
// Set up QR Error correction level of QR code （H At the highest level ） Specific level information
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
// The encoding used for the content
hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
// Set the margin of the picture
hints.put(EncodeHintType.MARGIN, 1);
// Generate matrix
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;
}
// Insert a picture LOGO
insertImage(image, imgPath, needCompress);
return image;
}
/**
* Insert LOG Picture into the generated QR code
* @param source
* QR code picture
* @param imgPath
* LOGO Picture address
* @param needCompress
* Is it compressed?
* @throws Exception
*/
private static void insertImage(BufferedImage source, String imgPath,
boolean needCompress) throws Exception {
File file = new File(imgPath);
if (!file.exists()) {
System.err.println(""+imgPath+" The file does not exist ！");
return;
}
Image src = ImageIO.read(new File(imgPath));
int width = src.getWidth(null);
int height = src.getHeight(null);
if (needCompress) { // Compress LOGO
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();
g.drawImage(image, 0, 0, null); // Draw a reduced image
g.dispose();
src = image;
}
// Insert 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();
}
/**
* @param destPath Storage directory
*/
public static void mkdirs(String destPath) {
File file = new File(destPath);
// When the folder does not exist ,mkdirs Automatically creates a multi-level directory , The difference in mkdir．(mkdir An exception is thrown if the parent directory does not exist )
if (!file.exists() && !file.isDirectory()) {
file.mkdirs();
}
}
}

其中，解析二维码图片时，需要使用 java.awt.Graphics2D 来分析图形和图像。

package com.dmeo.utils;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import com.google.zxing.LuminanceSource;
/**
*
* @description: This class mainly calls java.awt.Graphics2D To parse graphics and images
*/
public class BufferedImageLuminanceSource extends LuminanceSource{
private final BufferedImage image;
private final int left;
private final int top;
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;
}
@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);
}
}