首页 > 代码库 > Java实现二维码技术探讨。
Java实现二维码技术探讨。
Java生成二维码方法有三种：
1： 使用SwetakeQRCode在Java项目中生成二维码
http://swetake.com/qr/ 下载地址
或着http://sourceforge.jp/projects/qrcode/downloads/28391/qrcode.zip
这个是日本人写的，生成的是我们常见的方形的二维码
可以用中文 如：5677777ghjjjjj
2： 使用BarCode4j生成条形码和二维码
BarCode4j网址：http://sourceforge.net/projects/barcode4j/
barcode4j是使用datamatrix的二维码生成算法，为支持qr的算法
datamatrix是欧美的标准，qr为日本的标准，
barcode4j一般生成出来是长方形的
如：88777alec000yan
这个博客这方面说的挺清楚的：
http://baijinshan.iteye.com/blog/1004554
3、现在详细介绍第三种也是常用的方式：利用Zxing生成二维码
Zxing是Google提供的关于条码（一维码、二维码）的解析工具，提供了二维码的生成与解析的方法，现在我简单介绍一下使用Java利用Zxing生成与解析二维码。
第一步:将Zxing-core.jar 包加入项目中。
第二步 添加以下三个Java文件，三个文件功能如下：
MatrixToImageWriter.java 生成二维码图片。
BufferedImageLuminanceSource.java 解析二维码图片。
BarcodeFactory.java 生成带头像的二维码。
MatrixToImageWriter.java
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;
import javax.imageio.ImageIO;
import java.io.File;
import java.io.OutputStream;
import java.io.IOException;
import java.util.Hashtable;
import java.awt.image.BufferedImage;
public final class MatrixToImageWriter {
private static final int BLACK = 0xFF000000;
private static final int WHITE = 0xFFFFFFFF;
private MatrixToImageWriter() {
}
public static BufferedImage toBufferedImage(BitMatrix matrix) {
int width = matrix.getWidth();
int height = matrix.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, matrix.get(x, y) ? BLACK : WHITE);
}
}
return image;
}
public static void writeToFile(BitMatrix matrix, String format, File file) throws IOException {
BufferedImage image = toBufferedImage(matrix);
if (!ImageIO.write(image, format, file)) {
throw new IOException("Could not write an image of format " + format + " to " + file);
}
}
public static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException {
BufferedImage image = toBufferedImage(matrix);
if (!ImageIO.write(image, format, stream)) {
throw new IOException("Could not write an image of format " + format);
}
}
public static void main(String[] args) throws Exception {
String text = "二维码内容，可以是链接也可以是文本";
int width = 300;
int height = 300;
Hashtable hints = new Hashtable();
hints.put(EncodeHintType.CHARACTER_SET, "utf-8");//内容所使用编码
BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height, hints);
File outputFile = new File("E:/qrtest/生成普通二维码.jpg");
//File.separator
String format = "jpg";//二维码的图片格式
MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile);
}
}BufferedImageLuminanceSource.java
import com.google.zxing.Binarizer;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.EncodeHintType;
import com.google.zxing.LuminanceSource;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.Result;
import com.google.zxing.common.HybridBinarizer;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.util.HashMap;
import java.util.Map;
import javax.imageio.ImageIO;
public final 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);
}
public static void main(String[] args) {
//解析二维码
try {
MultiFormatReader formatReader = new MultiFormatReader();
String filePath = "E:/qrtest/生成普通二维码.jpg";
File file = new File(filePath);
BufferedImage image = ImageIO.read(file);
LuminanceSource source = new BufferedImageLuminanceSource(image);
Binarizer binarizer = new HybridBinarizer(source);
BinaryBitmap binaryBitmap = new BinaryBitmap(binarizer);
Map hints = new HashMap();
hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
Result result = formatReader.decode(binaryBitmap, hints);
System.out.println("result = " + result.toString());
System.out.println("resultFormat = " + result.getBarcodeFormat());
System.out.println("resultText = " + result.getText());
} catch (Exception e) {
e.printStackTrace();
}
}
}BarcodeFactory.java
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.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 BarcodeFactory {
// 图片宽度的一般
private static final int IMAGE_WIDTH = 80;
private static final int IMAGE_HEIGHT = 80;
private static final int IMAGE_HALF_WIDTH = IMAGE_WIDTH / 2;
private static final int FRAME_WIDTH = 2;
// 二维码写码器
private static MultiFormatWriter mutiWriter = new MultiFormatWriter();
/**
* 将srcImagePath嵌入到destImagePath
*/
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 {
// 读取源图像
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);
// 生成二维码
BitMatrix matrix = mutiWriter.encode(content, BarcodeFormat.QR_CODE, width, height, hint);
// 二维矩阵转为一维像素数组
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++) {
// 读取图片
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];
}
// 在图片四周形成边框
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 > 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 > 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 > halfH + IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH + IMAGE_HALF_WIDTH + FRAME_WIDTH)) {
pixels[y * width + x] = 0xfffffff;
} else {
// 此处可以修改二维码的颜色，可以分别制定二维码和背景的颜色；
pixels[y * width + x] = matrix.get(x, y) ? 0xff000000 : 0xfffffff;
}
}
}
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
image.getRaster().setDataElements(0, 0, width, height, pixels);
return image;
}
/**
* 把传入的原始图像按高度和宽度进行缩放，生成符合要求的图标
*
* @param srcImageFile
* 源文件地址
* @param height
* 目标高度
* @param width
* 目标宽度
* @param hasFiller
* 比例不对时是否需要补白：true为补白; false为不补白;
* @throws IOException
*/
private static BufferedImage scale(String srcImageFile, int height, int width, boolean hasFiller) throws IOException {
double ratio = 0.0; // 缩放比例
File file = new File(srcImageFile);
BufferedImage srcImage = ImageIO.read(file);
Image destImage = srcImage.getScaledInstance(width, height, BufferedImage.SCALE_SMOOTH);
// 计算比例
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) {// 补白
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) {
//src.jpg为头像文件
BarcodeFactory.encode("http://www.baidu.com", 300, 300, "E:/qrtest/src.jpg","E:/qrtest/生成带头像的二维码.jpg");
}
}
声明：以上内容来自用户投稿及互联网公开渠道收集整理发布，本网站不拥有所有权，未作人工编辑处理，也不承担相关法律责任，若内容有误或涉及侵权可进行投诉： 投诉/举报 工作人员会在5个工作日内联系你，一经查实，本站将立刻删除涉嫌侵权内容。