java制作二维码笔记

1、使用第三方架包

  使用第三最流行的架包zxing，GitHub的地址：https://github.com/zxing/zxing/tree/zxing-3.0.0。也可以从这里直接下载。

2、代码编写

MatrixToImageWriter类：

import javax.imageio.ImageIO;

import com.google.zxing.common.BitMatrix;

import java.io.File;
import java.io.OutputStream;
import java.io.IOException;
import java.awt.image.BufferedImage;
public 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);
	     }
	 }
}

 测试Test类：

 

import java.io.File;
import java.util.Hashtable;


import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;

public class Test {

	public static void main(String[] args) throws Exception{
		String text = "http://www.baidu.com";//二维码的内容
       	 	int width = 400;  
        	int height = 400;  
        	String format = "jpg";    
        	Hashtable hints= new Hashtable();  
        	hints.put(EncodeHintType.CHARACTER_SET, "utf-8");  
        	BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height,hints);  
       	 	File outputFile = new File("f://112.jpg");  
        	MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile); 
        	System.out.println("It is ok!");
 	}
}