二维码：是用某种特定的几何图形按一定规律在平面（二维方向上）分布的、黑白相间的、记录数据符号信息的图形；在代码编制上巧妙地利用构成计算机内部逻辑基础的“0”、“1”比特流的概念，使用若干个与二进制相对应的几何形体来表示文字数值信息，通过图象输入设备或光电扫描设备自动识读以实现信息自动处理：它具有条码技术的一些共性：每种码制有其特定的字符集；每个字符占有一定的宽度；具有一定的校验功能等。同时还具有对不同行的信息自动识别功能、及处理图形旋转变化点。而我在这里要讲述的是目前流行的常用二维码QRCode。
QR Code码，英文全称（Quick Response Code）是由Denso公司于1994年9月研制的一种矩阵二维码符号，它具有一维条码及其它二维条码所具有的信息容量大、可靠性高、可表示汉字及图象多种文字信息、保密防伪性强等优点。——百度百科
QRCode 由于其内部结构的特定布局和设计使得它具有超高速的识读能力和高纠错能力。好了详细的描述大家可以去百度查询各种资料。在这篇随笔里我主要采用springboot框架来生成QRCode二维码。话不多说，直接上码吧。
步骤一：依赖包
<!-- springboot基础依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- 二维码生成器依赖 -->
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>core</artifactId>
<version>3.3.0</version>
</dependency>
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>javase</artifactId>
<version>3.3.0</version>
</dependency>
步骤二：生成二维码的工具类
import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.util.Hashtable;
/**
* @author chaoyou
* @email
* @date 2019-11-22 16:04
* @Description
*/
public class QRCodeUtil {
private static final String CHARSET = "utf-8";
private static final String FORMAT_NAME = "JPG";
// 二维码尺寸
private static final int QRCODE_SIZE = 300;
// LOGO宽度
private static final int WIDTH = 60;
// LOGO高度
private static final int HEIGHT = 60;
private static BufferedImage createImage(String content, String imgPath,
boolean needCompress) throws Exception {
Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
hints.put(EncodeHintType.CHARACTER_SET, CHARSET); // 文本编码格式
hints.put(EncodeHintType.MARGIN, 1);
BitMatrix bitMatrix = new MultiFormatWriter().encode(content,
BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints); // 设置生成二维码的大小
int width = bitMatrix.getWidth();
int height = bitMatrix.getHeight();
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB); // 设置二维码中logo的大小
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000
: 0xFFFFFFFF);
}
}
if (imgPath == null || "".equals(imgPath)) {
return image;
}
// 插入图片
QRCodeUtil.insertImage(image, imgPath, needCompress);
return image;
}
/**
* 插入LOGO
*
* @param source 二维码图片
* @param imgPath LOGO图片地址
* @param needCompress 是否压缩
* @throws Exception
*/
private static void insertImage(BufferedImage source, String imgPath,
boolean needCompress) throws Exception {
File file = new File(imgPath);
if (!file.exists()) {
System.err.println(""+imgPath+" 该文件不存在！");
return;
}
Image src = ImageIO.read(new File(imgPath));
int width = src.getWidth(null);
int height = src.getHeight(null);
if (needCompress) { // 压缩LOGO
if (width > WIDTH) {
width = WIDTH;
}
if (height > HEIGHT) {
height = HEIGHT;
}
Image image = src.getScaledInstance(width, height,
Image.SCALE_SMOOTH);
BufferedImage tag = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics g = tag.getGraphics();
g.drawImage(image, 0, 0, null); // 绘制缩小后的图
g.dispose();
src = image;
}
// 插入LOGO
Graphics2D graph = source.createGraphics();
int x = (QRCODE_SIZE - width) / 2;
int y = (QRCODE_SIZE - height) / 2;
graph.drawImage(src, x, y, width, height, null);
Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);
graph.setStroke(new BasicStroke(3f));
graph.draw(shape);
graph.dispose();
}
/**
* 生成二维码(内嵌LOGO)
*
* @param content 内容
* @param imgPath LOGO地址
* @param destPath 存放目录
* @param needCompress 是否压缩LOGO
* @throws Exception
*/
public static void encode(String content, String imgPath, String destPath,
boolean needCompress,Integer NaireID) throws Exception {
BufferedImage image = QRCodeUtil.createImage(content, imgPath,
needCompress);
mkdirs(destPath);
String file = NaireID+".jpg";
ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));
}
/**
* 当文件夹不存在时，mkdirs会自动创建多层目录，区别于mkdir．(mkdir如果父目录不存在则会抛出异常)
* @param destPath 存放目录
*/
public static void mkdirs(String destPath) {
File file =new File(destPath);
//当文件夹不存在时，mkdirs会自动创建多层目录，区别于mkdir．(mkdir如果父目录不存在则会抛出异常)
if (!file.exists() && !file.isDirectory()) {
file.mkdirs();
}
}
/**
* 生成二维码(内嵌LOGO)
*
* @param content 内容
* @param imgPath LOGO地址
* @param destPath 存储地址
* @throws Exception
*/
public static void encode(String content, String imgPath, String destPath,Integer NaireID)
throws Exception {
QRCodeUtil.encode(content, imgPath, destPath, false, NaireID);
}
/**
* 生成二维码
*
* @param content 内容
* @param destPath 存储地址
* @param needCompress 是否压缩LOGO
* @throws Exception
*/
public static void encode(String content, String destPath,
boolean needCompress,Integer NaireID) throws Exception {
QRCodeUtil.encode(content, null, destPath, needCompress,NaireID);
}
/**
* 生成二维码
*
* @param content 内容
* @param destPath 存储地址
* @param naireid 自定义问卷二维码编号
* @throws Exception
*/
public static void encode(String content, String destPath,Integer naireid) throws Exception {
QRCodeUtil.encode(content, null, destPath, false,naireid);
}
/**
* 生成二维码(内嵌LOGO)
*
* @param content 内容
* @param imgPath LOGO地址
* @param output 输出流
* @param needCompress 是否压缩LOGO
* @throws Exception
*/
public static void encode(String content, String imgPath,
OutputStream output, boolean needCompress) throws Exception {
BufferedImage image = QRCodeUtil.createImage(content, imgPath,
needCompress);
ImageIO.write(image, FORMAT_NAME, output);
}
/**
* 生成二维码
*
* @param content 内容
* @param output 输出流
* @throws Exception
*/
public static void encode(String content, OutputStream output) throws Exception {
QRCodeUtil.encode(content, null, output, false);
}
/**
* 解析二维码
*
* @param file 二维码图片
* @return
* @throws Exception
*/
public static String decode(File file) throws Exception {
BufferedImage image;
image = ImageIO.read(file);
if (image == null) {
return null;
}
BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(
image);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Result result;
Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
hints.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
hints.put(DecodeHintType.PURE_BARCODE, Boolean.TRUE);
result = new MultiFormatReader().decode(bitmap, hints);
String resultStr = result.getText();
return resultStr;
}
/**
* 解析二维码
*
* @param path 二维码图片地址
* @return
* @throws Exception
*/
public static String decode(String path) throws Exception {
return QRCodeUtil.decode(new File(path));
}
}
步骤三：生成/解析二维码方法
package cn.suancloud.pdfjk;
import cn.suancloud.pdfjk.api.util.EncryptUtil;
import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.multi.qrcode.QRCodeMultiReader;
import com.google.zxing.qrcode.QRCodeReader;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.encoder.QRCode;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.*;
import java.nio.file.FileSystems;
import java.nio.file.Path;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Hashtable;
import java.util.Optional;
/**
* @author chaoyou
* @email lichaoyou@suancioud.cn
* @date 2019-11-21 18:00
* @Description
*/
public class QRCodeGenerator {
private static final String QR_CODE_IMAGE_PATH = "C:\Users\Administrator\Pictures\myQERCode.jpg";
private static final String CHARSET = "utf-8";
/**
* 生成二维码
* @param text 二维码中存放的文本内容
* @param width 长度
* @param height 宽度
* @param filePath 二维码存放途径
* @throws Exception
*/
public static void generateQRCodeImage(String text, int width, int height, String filePath) throws Exception {
// 初始化QRC对象
QRCodeWriter qrCodeWriter = new QRCodeWriter();
// 加密文本数据
text = EncryptUtil.encryptAES(text);
// 生成二维码
BitMatrix bitMatrix = qrCodeWriter.encode(text, BarcodeFormat.QR_CODE, width, height);
// 获取指定路径的操作权限
Path path = FileSystems.getDefault().getPath(filePath);
// 把生成的二维码写入到指定的路径
MatrixToImageWriter.writeToPath(bitMatrix, "PNG", path);
}
/**
* 解析二维码
*
* @param path 二维码图片地址
* @return
* @throws Exception
*/
public static String decode(String path) throws Exception {
// 获取指定路径图片资源的IO
File file = new File(path);
BufferedImage image;
image = ImageIO.read(file);
if (image == null) {
return null;
}
BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(
image);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Result result;
Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
hints.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
hints.put(DecodeHintType.PURE_BARCODE, Boolean.TRUE);
result = new MultiFormatReader().decode(bitmap, hints);
String resultStr = result.getText();
return resultStr;
}
}