标签:
转载地址:点击打开链接
二维码,是一种采用黑白相间的平面几何图形通过相应的编码算法来记录文字、图片、网址等信息的条码图片。如下图
二维码的特点:
1. 高密度编码,信息容量大
可容纳多达1850个大写字母或2710个数字或1108个字节,或500多个汉字,比普通条码信息容量约高几十倍。
2. 编码范围广
该条码可以把图片、声音、文字、签字、指纹等可以数字化的信息进行编码,用条码表示出来;可以表示多种语言文字;可表示图像数据。
3. 容错能力强,具有纠错功能
这使得二维条码因穿孔、污损等引起局部损坏时,照样可以正确得到识读,损毁面积达50%仍可恢复信息。
4. 译码可靠性高
它比普通条码译码错误率百万分之二要低得多,误码率不超过千万分之一。
5. 可引入加密措施
保密性、防伪性好。
6. 成本低,易制作,持久耐用
正因为以上这些特点,二维码现在越来越流行,应用也是越来越广(详细了解请见百度百科,介绍不是本篇重点),所以掌握如何开发二维码是非常不错的知识储备,因此本篇博文将为大家讲解如何生成、解析二维码。
所需jar包:QRCode.jar
http://download.csdn.net/detail/wangpeng047/4008532
TwoDimensionCode类:二维码操作核心类
- package qrcode;
-
- import java.awt.Color;
- import java.awt.Graphics2D;
- import java.awt.image.BufferedImage;
- import java.io.File;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.OutputStream;
-
- import javax.imageio.ImageIO;
-
- import jp.sourceforge.qrcode.QRCodeDecoder;
- import jp.sourceforge.qrcode.exception.DecodingFailedException;
-
- import com.swetake.util.Qrcode;
-
- public class TwoDimensionCode {
-
-
- public void encoderQRCode(String content, String imgPath) {
- this.encoderQRCode(content, imgPath, "png", 7);
- }
-
-
- public void encoderQRCode(String content, OutputStream output) {
- this.encoderQRCode(content, output, "png", 7);
- }
-
-
- public void encoderQRCode(String content, String imgPath, String imgType) {
- this.encoderQRCode(content, imgPath, imgType, 7);
- }
-
-
- public void encoderQRCode(String content, OutputStream output, String imgType) {
- this.encoderQRCode(content, output, imgType, 7);
- }
-
-
- public void encoderQRCode(String content, String imgPath, String imgType, int size) {
- try {
- BufferedImage bufImg = this.qRCodeCommon(content, imgType, size);
-
- File imgFile = new File(imgPath);
-
- ImageIO.write(bufImg, imgType, imgFile);
- } catch (Exception e) {
- e.printStackTrace();
- }
- }
-
-
- public void encoderQRCode(String content, OutputStream output, String imgType, int size) {
- try {
- BufferedImage bufImg = this.qRCodeCommon(content, imgType, size);
-
- ImageIO.write(bufImg, imgType, output);
- } catch (Exception e) {
- e.printStackTrace();
- }
- }
-
-
- private BufferedImage qRCodeCommon(String content, String imgType, int size) {
- BufferedImage bufImg = null;
- try {
- Qrcode qrcodeHandler = new Qrcode();
-
- qrcodeHandler.setQrcodeErrorCorrect(‘M‘);
- qrcodeHandler.setQrcodeEncodeMode(‘B‘);
-
- qrcodeHandler.setQrcodeVersion(size);
-
- byte[] contentBytes = content.getBytes("utf-8");
-
- int imgSize = 67 + 12 * (size - 1);
- bufImg = new BufferedImage(imgSize, imgSize, BufferedImage.TYPE_INT_RGB);
- Graphics2D gs = bufImg.createGraphics();
-
- gs.setBackground(Color.WHITE);
- gs.clearRect(0, 0, imgSize, imgSize);
-
-
- gs.setColor(Color.BLACK);
-
- int pixoff = 2;
-
- if (contentBytes.length > 0 && contentBytes.length < 800) {
- boolean[][] codeOut = qrcodeHandler.calQrcode(contentBytes);
- for (int i = 0; i < codeOut.length; i++) {
- for (int j = 0; j < codeOut.length; j++) {
- if (codeOut[j][i]) {
- gs.fillRect(j * 3 + pixoff, i * 3 + pixoff, 3, 3);
- }
- }
- }
- } else {
- throw new Exception("QRCode content bytes length = " + contentBytes.length + " not in [0, 800].");
- }
- gs.dispose();
- bufImg.flush();
- } catch (Exception e) {
- e.printStackTrace();
- }
- return bufImg;
- }
-
-
- public String decoderQRCode(String imgPath) {
-
- File imageFile = new File(imgPath);
- BufferedImage bufImg = null;
- String content = null;
- try {
- bufImg = ImageIO.read(imageFile);
- QRCodeDecoder decoder = new QRCodeDecoder();
- content = new String(decoder.decode(new TwoDimensionCodeImage(bufImg)), "utf-8");
- } catch (IOException e) {
- System.out.println("Error: " + e.getMessage());
- e.printStackTrace();
- } catch (DecodingFailedException dfe) {
- System.out.println("Error: " + dfe.getMessage());
- dfe.printStackTrace();
- }
- return content;
- }
-
-
- public String decoderQRCode(InputStream input) {
- BufferedImage bufImg = null;
- String content = null;
- try {
- bufImg = ImageIO.read(input);
- QRCodeDecoder decoder = new QRCodeDecoder();
- content = new String(decoder.decode(new TwoDimensionCodeImage(bufImg)), "utf-8");
- } catch (IOException e) {
- System.out.println("Error: " + e.getMessage());
- e.printStackTrace();
- } catch (DecodingFailedException dfe) {
- System.out.println("Error: " + dfe.getMessage());
- dfe.printStackTrace();
- }
- return content;
- }
-
- public static void main(String[] args) {
- String imgPath = "G:/TDDOWNLOAD/Michael_QRCode.png";
- String encoderContent = "Hello 大大、小小,welcome to QRCode!" + "\nMyblog [ http://sjsky.iteye.com ]" + "\nEMail [ sjsky007@gmail.com ]";
- TwoDimensionCode handler = new TwoDimensionCode();
- handler.encoderQRCode(encoderContent, imgPath, "png");
- System.out.println("========encoder success");
-
-
- String decoderContent = handler.decoderQRCode(imgPath);
- System.out.println("解析结果如下:");
- System.out.println(decoderContent);
- System.out.println("========decoder success!!!");
- }
- }
TwoDimensionCodeImage 类:二维码图片对象
- package qrcode;
-
- import java.awt.image.BufferedImage;
-
- import jp.sourceforge.qrcode.data.QRCodeImage;
-
- public class TwoDimensionCodeImage implements QRCodeImage {
-
- BufferedImage bufImg;
-
- public TwoDimensionCodeImage(BufferedImage bufImg) {
- this.bufImg = bufImg;
- }
-
- @Override
- public int getHeight() {
- return bufImg.getHeight();
- }
-
- @Override
- public int getPixel(int x, int y) {
- return bufImg.getRGB(x, y);
- }
-
- @Override
- public int getWidth() {
- return bufImg.getWidth();
- }
-
- }
上面的java代码,笔者已经进行了简单的封装,方便大家适用不同场合,希望对大家能有所帮助。
[转]java二维码生成与解析代码实现
标签:
原文地址:http://www.cnblogs.com/gangben/p/4387584.html