java 生成二维码

Posted 2020-10-05 mike11

这里主要使用Google的zxing架包。

<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>core</artifactId>
<version>3.2.1</version>
</dependency>

注意：2.1版本后需要jdk1.7支持

API：　　

package crunchify.com.tutorial;
 
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.EnumMap;
import java.util.Map;
 
import javax.imageio.ImageIO;
 
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
 
/**
 * @author Crunchify.com
 * Updated: 03/20/2016 - added code to narrow border size 
 */
 
public class CrunchifyQRCode {
 
	// Tutorial: http://zxing.github.io/zxing/apidocs/index.html
 
	public static void main(String[] args) {
		String myCodeText = "http://crunchify.com/";
		String filePath = "/Users/appshah/Documents/CrunchifyQR.png";
		int size = 250;
		String fileType = "png";
		File myFile = new File(filePath);
		try {
			
			Map<EncodeHintType, Object> hintMap = new EnumMap<EncodeHintType, Object>(EncodeHintType.class);
			hintMap.put(EncodeHintType.CHARACTER_SET, "UTF-8");
			
			// Now with zxing version 3.2.1 you could change border size (white border size to just 1)
			hintMap.put(EncodeHintType.MARGIN, 1); /* default = 4 */
			hintMap.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);
 
			QRCodeWriter qrCodeWriter = new QRCodeWriter();
			BitMatrix byteMatrix = qrCodeWriter.encode(myCodeText, BarcodeFormat.QR_CODE, size,
					size, hintMap);
			int CrunchifyWidth = byteMatrix.getWidth();
			BufferedImage image = new BufferedImage(CrunchifyWidth, CrunchifyWidth,
					BufferedImage.TYPE_INT_RGB);
			image.createGraphics();
 
			Graphics2D graphics = (Graphics2D) image.getGraphics();
			graphics.setColor(Color.WHITE);
			graphics.fillRect(0, 0, CrunchifyWidth, CrunchifyWidth);
			graphics.setColor(Color.BLACK);
 
			for (int i = 0; i < CrunchifyWidth; i++) {
				for (int j = 0; j < CrunchifyWidth; j++) {
					if (byteMatrix.get(i, j)) {
						graphics.fillRect(i, j, 1, 1);
					}
				}
			}
			ImageIO.write(image, fileType, myFile);
		} catch (WriterException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		System.out.println("\n\nYou have successfully created QR Code.");
	}
}

生成：