Java实现二维码生成

title: Java实现二维码生成

categories: “Java”

前言

日前生活上存在很多扫描二维码的场景，支付、加好友…等操作都需要扫描二维码，然后我就在想Java能不能实现二维码的生成呢？百度一搜，还是有的，看了一些，决定自己试试看，所以下面是我用Java代码写的二维码实现，但是弊端就是只能在个人pc电脑上生成，没有写成一个完整的网页小功能，我想下一章博客，我会写写的。

准备工作

1.首先你得在个人pc安装Java环境。这个百度一搜，都有的，我就不写了。

2.编程环境安装好了，你得有一个好玩的编辑器软件，建议使用IntelliJ IDEA ，这个博客使用的编程编辑器，我是使用eclipse的，没想到吧，哈哈。

3.Java其实是提供了一个库来实现二维码的生成的，就是这个core-3.0.0.jar，网站我忘了，但我可以提供一下我使用的这个jar包，链接：链接：https://pan.baidu.com/s/1EjSbBfhGyWzTWNynT6lNWA
提取码：vc0h

4.下载了core-3.0.0.jar包，然后引进项目。如何在eclipse新建Java probject中引入jar包，这个我在这里就不详细说明了，请自行百度吧。

开始

1.新建工程项目，引入core-3.0.0.jar包后，新建一个名为BufferedImageLuminanceSource.java类

—Java

import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.util.Hashtable;
import java.util.Random;import javax.imageio.ImageIO;import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.LuminanceSource;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;public class BufferedImageLuminanceSource {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;public BufferedImageLuminanceSource(BufferedImage image) {// TODO Auto-generated constructor stub}private static BufferedImage createImage(String content, String imgPath,boolean needCompress) throws Exception {Hashtable hints = new Hashtable();hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);hints.put(EncodeHintType.CHARACTER_SET, CHARSET);hints.put(EncodeHintType.MARGIN, 1);BitMatrix bitMatrix = new MultiFormatWriter().encode(content,BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);int width = bitMatrix.getWidth();int height = bitMatrix.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, bitMatrix.get(x, y) ? 0xFF000000: 0xFFFFFFFF);}}if (imgPath == null || "".equals(imgPath)) {return image;}// 插入图片BufferedImageLuminanceSource.insertImage(image, imgPath, needCompress);return image;}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LOGOif (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LOGOGraphics2D 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();}public static void encode(String content, String imgPath, String destPath,boolean needCompress) throws Exception {BufferedImage image = BufferedImageLuminanceSource.createImage(content, imgPath,needCompress);mkdirs(destPath);String file = new Random().nextInt(99999999)+".jpg";ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));}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();}}public static void encode(String content, String imgPath, String destPath)throws Exception {BufferedImageLuminanceSource.encode(content, imgPath, destPath, false);}public static void encode(String content, String destPath,boolean needCompress) throws Exception {BufferedImageLuminanceSource.encode(content, null, destPath, needCompress);}public static void encode(String content, String destPath) throws Exception {BufferedImageLuminanceSource.encode(content, null, destPath, false);}public static void encode(String content, String imgPath,OutputStream output, boolean needCompress) throws Exception {BufferedImage image = BufferedImageLuminanceSource.createImage(content, imgPath,needCompress);ImageIO.write(image, FORMAT_NAME, output);}public static void encode(String content, OutputStream output)throws Exception {BufferedImageLuminanceSource.encode(content, null, output, false);}public static String decode(File file) throws Exception {BufferedImage image;image = ImageIO.read(file);if (image == null) {return null;}Object source = new BufferedImageLuminanceSource(image);BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer((LuminanceSource) source));Result result;Hashtable hints = new Hashtable();hints.put(DecodeHintType.CHARACTER_SET, CHARSET);result = new MultiFormatReader().decode(bitmap, hints);String resultStr = result.getText();return resultStr;}public static String decode(String path) throws Exception {return BufferedImageLuminanceSource.decode(new File(path));}public static void main(String[] args) throws Exception {String text = "http://hongkaiqing.cn";BufferedImageLuminanceSource.encode(text, "d:/MyWorkDoc/my180.jpg", "d:/MyWorkDoc", true);}}

在创建一个命名为：QRCodeUtil.java类

—Java


import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.util.Hashtable;
import java.util.Random;import javax.imageio.ImageIO;import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.LuminanceSource;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;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 hints = new Hashtable();hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);hints.put(EncodeHintType.CHARACTER_SET, CHARSET);hints.put(EncodeHintType.MARGIN, 1);BitMatrix bitMatrix = new MultiFormatWriter().encode(content,BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);int width = bitMatrix.getWidth();int height = bitMatrix.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, bitMatrix.get(x, y) ? 0xFF000000: 0xFFFFFFFF);}}if (imgPath == null || "".equals(imgPath)) {return image;}// 插入图片QRCodeUtil.insertImage(image, imgPath, needCompress);return image;}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LOGOif (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LOGOGraphics2D 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();}public static void encode(String content, String imgPath, String destPath,boolean needCompress) throws Exception {BufferedImage image = QRCodeUtil.createImage(content, imgPath,needCompress);mkdirs(destPath);String file = new Random().nextInt(99999999)+".jpg";ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));}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();}}public static void encode(String content, String imgPath, String destPath)throws Exception {QRCodeUtil.encode(content, imgPath, destPath, false);}public static void encode(String content, String destPath,boolean needCompress) throws Exception {QRCodeUtil.encode(content, null, destPath, needCompress);}public static void encode(String content, String destPath) throws Exception {QRCodeUtil.encode(content, null, destPath, false);}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);}public static void encode(String content, OutputStream output)throws Exception {QRCodeUtil.encode(content, null, output, false);}public static String decode(File file) throws Exception {BufferedImage image;image = ImageIO.read(file);if (image == null) {return null;}Object source = new BufferedImageLuminanceSource(image);BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer((LuminanceSource) source));Result result;Hashtable hints = new Hashtable();hints.put(DecodeHintType.CHARACTER_SET, CHARSET);result = new MultiFormatReader().decode(bitmap, hints);String resultStr = result.getText();return resultStr;}public static String decode(String path) throws Exception {return QRCodeUtil.decode(new File(path));}public static void main(String[] args) throws Exception {String text = "http://www.hongkaiqing.cn";QRCodeUtil.encode(text, "d:/MyWorkDoc", true);}}

然后运行QRCodeUtil.java类，就会在你个人pc电脑的d盘MyWorkDoc文件夹下生成一个二维码图片，效果如下：如果你个人pc电脑的d盘目录下没有MyWorkDoc文件夹，程序则会自动帮你生成该文件夹。

最后

其实是QRCodeUtil.java类中这个main方法决定程序在那个文件夹下生成二维码，String text 决定二维码扫描后，显示的内容的

 public static void main(String[] args) throws Exception {String text = "http://www.hongkaiqing.cn";QRCodeUtil.encode(text, "d:/MyWorkDoc", true);}

这个项目demo源码存放在GitHub上，链接：https://github.com/hongkq/QR-code

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