zxing实现java二维码生成和解析

转自：https://blog.csdn.net/javaweiming/article/details/72844581

生成二维码的方式有很多，在此简单介绍Google的zxing使用

先加载需要用到的包，pom.xml文件里面添加：

1. <!-- 二维码生成 -->
2. <dependency>
3. <groupId>com.google.zxing</groupId>
4. <artifactId>core</artifactId>
5. <version>2.2</version>
6. </dependency>
7.  
8. <dependency>
9. <groupId>com.google.zxing</groupId>
10. <artifactId>javase</artifactId>
11. <version>2.2</version>
12. </dependency>

工具类代码

1. import java.awt.image.BufferedImage;
2. import java.io.File;
3. import java.io.IOException;
4. import java.nio.file.FileSystems;
5. import java.nio.file.Path;
6. import java.util.HashMap;
7. import java.util.Map;
8.  
9. import javax.imageio.ImageIO;
10.  
11. import com.google.zxing.BarcodeFormat;
12. import com.google.zxing.Binarizer;
13. import com.google.zxing.BinaryBitmap;
14. import com.google.zxing.DecodeHintType;
15. import com.google.zxing.EncodeHintType;
16. import com.google.zxing.LuminanceSource;
17. import com.google.zxing.MultiFormatReader;
18. import com.google.zxing.MultiFormatWriter;
19. import com.google.zxing.NotFoundException;
20. import com.google.zxing.Result;
21. import com.google.zxing.WriterException;
22. import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
23. import com.google.zxing.client.j2se.MatrixToImageWriter;
24. import com.google.zxing.common.BitMatrix;
25. import com.google.zxing.common.HybridBinarizer;
26. import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
27.  
28. import net.sf.json.JSONObject;
29.  
30. /**
31. *
32. * 处理图片url
33. */
34. public class QRCodeUtil {
35.  
36. public static void main(String[] args) throws WriterException, IOException {
37. testEncode();
38. testDecode();
39. }
40.  
41. /**
42. * 生成图像
43. *
44. * @throws WriterException
45. * @throws IOException
46. */
47. public static void testEncode() throws WriterException, IOException {
48. String filePath = "D://";
49. String fileName = "text.png";
50. JSONObject json = new JSONObject();
51. json.put("url", "https://www.baidu.com");
52. json.put("author", "zwm");
53. String content = json.toString();// 内容
54. int width = 200; // 图像宽度
55. int height = 200; // 图像高度
56. String format = "png";// 图像类型
57. Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>();
58. hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
59. BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);// 生成矩阵
60. Path path = FileSystems.getDefault().getPath(filePath, fileName);
61. File file = new File(filePath + fileName);
62. MatrixToImageWriter.writeToFile(bitMatrix, format, file);// 输出图像
63. System.out.println("图片文件已经生成.请于D盘查找");
64. }
65.  
66. /**
67. * 解析图像
68. */
69. public static void testDecode() {
70. String filePath = "D://text.png";
71. BufferedImage image;
72. try {
73. image = ImageIO.read(new File(filePath));
74. LuminanceSource source = new BufferedImageLuminanceSource(image);
75. Binarizer binarizer = new HybridBinarizer(source);
76. BinaryBitmap binaryBitmap = new BinaryBitmap(binarizer);
77. Map<DecodeHintType, Object> hints = new HashMap<DecodeHintType, Object>();
78. hints.put(DecodeHintType.CHARACTER_SET, "UTF-8");
79. Result result = new MultiFormatReader().decode(binaryBitmap, hints);// 对图像进行解码
80. JSONObject content = JSONObject.fromObject(result.getText());
81. System.out.println("图片中内容： ");
82. System.out.println("author:" + content.getString("author"));
83. System.out.println("url： " + content.getString("url"));
84. System.out.println("图片中格式： ");
85. System.out.println("encode： " + result.getBarcodeFormat());
86. } catch (IOException e) {
87. e.printStackTrace();
88. } catch (NotFoundException e) {
89. e.printStackTrace();
90. }
91. }
92.  
93. public static BufferedImage createQRCode(final String url) throws WriterException, IOException {
94. BufferedImage image = null;
95. // 二维码图片输出流
96. MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
97. HashMap<EncodeHintType, Comparable> hints = new HashMap<EncodeHintType, Comparable>();
98. // 设置编码方式
99. hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
100. // 设置QR二维码的纠错级别（H为最高级别）具体级别信息
101. hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
102. BitMatrix bitMatrix = multiFormatWriter.encode(url, BarcodeFormat.QR_CODE, 400, 400, hints);
103. bitMatrix = updateBit(bitMatrix, 10);
104. image = MatrixToImageWriter.toBufferedImage(bitMatrix);
105. return image;
106. }
107.  
108. /**
109. * 自定义白边边框宽度
110. *
111. * @param matrix
112. * @param margin
113. * @return
114. */
115. private static BitMatrix updateBit(final BitMatrix matrix, final int margin) {
116. int tempM = margin * 2;
117. // 获取二维码图案的属性
118. int[] rec = matrix.getEnclosingRectangle();
119. int resWidth = rec[2] + tempM;
120. int resHeight = rec[3] + tempM;
121. // 按照自定义边框生成新的BitMatrix
122. BitMatrix resMatrix = new BitMatrix(resWidth, resHeight);
123. resMatrix.clear();
124. // 循环，将二维码图案绘制到新的bitMatrix中
125. for (int i = margin; i < resWidth - margin; i++) {
126. for (int j = margin; j < resHeight - margin; j++) {
127. if (matrix.get(i - margin + rec[0], j - margin + rec[1])) {
128. resMatrix.set(i, j);
129. }
130. }
131. }
132. return resMatrix;
133. }
134. }

直接运行即可看到效果，其中 createQRCode是用于直接将生成的二维码以流的形式在页面上输出，调用方法如下：

1. /**
2. * 根据URL生成二维码
3. * @param model
4. * @param request
5. * @param response
6. * @throws MaHuaServiceHandleException
7. */
8. @RequestMapping("/getQRCode")
9. public void getQRCode(final @RequestAttribute(ReqBean.NAME) ReqBean reqBean,HttpServletRequest request, HttpServletResponse response){
10. String url = "http://www.baidu.com";
11. //二维码图片输出流
12. OutputStream out = null;
13. try{
14. response.setContentType("image/jpeg;charset=UTF-8");
15. BufferedImage image = QRCodeUtil.createQRCode(url);
16. //实例化输出流对象
17. out = response.getOutputStream();
18. //画图
19. ImageIO.write(image, "png", response.getOutputStream());
20. out.flush();
21. out.close();
22. }catch (Exception e){
23. e.printStackTrace();
24. }finally {
25. try{
26. if (null != response.getOutputStream()) {
27. response.getOutputStream().close();
28. }
29. if (null != out) {
30. out.close();
31. }
32. }catch(Exception e){
33. e.printStackTrace();
34. }
35. }
36. }

 在页面上调用此方法：

 <div style="height:100%;100%"><img style="100%" id="QRCode" src="./activity/getQRCode.do?" /></div>  

  这样生成的二维码则会再这个div的地方显示出来