Java利用Zxing生成二维码

Java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

1、二维码的生成

　　1.1 将Zxing-core.jar 包加入到classpath下。

　　 1.2 二维码的生成需要借助MatrixToImageWriter类，该类是由Google提供的，可以将该类拷贝到源码中，这里我将该类的源码贴上，可以直接使用。

import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;

import java.io.File;

import java.io.OutputStream;

import java.io.IOException;

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);

}

}

}

1.3 编写生成二维码的实现代码

try {

String content = "120605181003;http://www.cnblogs.com/jtmjx";
String path = "C:/Users/Administrator/Desktop/testImage";

MultiFormatWriter multiFormatWriter = new MultiFormatWriter();

Map hints = new HashMap();
hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
BitMatrix bitMatrix = multiFormatWriter.encode(content, BarcodeFormat.QR_CODE, 400, 400,hints);
File file1 = new File(path,"餐巾纸.jpg");
MatrixToImageWriter.writeToFile(bitMatrix, "jpg", file1);

} catch (Exception e) {

e.printStackTrace();

}

　现在运行后即可生成一张二维码图片，是不是很简单啊？ 接下来我们看看如何解析二维码

　2、二维码的解析

　　2.1 将Zxing-core.jar 包加入到classpath下。　　

　　2.2 和生成一样，我们需要一个辅助类（ BufferedImageLuminanceSource），同样该类Google也提供了，这里我同样将该类的源码贴出来，可以直接拷贝使用个，省去查找的麻烦

　　BufferedImageLuminanceSource

import com.google.zxing.LuminanceSource;

import java.awt.Graphics2D;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

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);

}

}

　2.3 编写解析二维码的实现代码

　try {

MultiFormatReader formatReader = new MultiFormatReader();

String filePath = “C:/Users/Administrator/Desktop/testImage/test.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();
}
现在运行后可以看到控制台打印出了二维码的内容。
自己留着备忘。