java二维码生成技术
自从微信扫描出世，二维码扫描逐渐已经成为一种主流的信息传递和交换方式。下面就介绍一下我学习到的这种二维码生成方式。预计再过不久身份证户口本等都会使用二维码识别了，今天就做一个实验案例；
二维码主要实现这两点：
1.生成任意的二维码。
2.在二维码的中间加入图像。
一、准备工作。
准备QR二维码3.0 版本的core包和一张jpg图片。
下载QR二维码包。
当然你也可以从maven仓库下载jar 包: http://central.maven.org/maven2/com/google/zxing/core/
二、程序设计
1、启动eclipse，新建一个java项目，命好项目名（本例取名为QRCodeSoft）。点下一步：
2、导入zxing.jar 包, 我这里用的是3.0 版本的core包：点“添加外部JAR(X)…”。
3、新建两个类，分别是：
BufferedImageLuminanceSource.java
QRCodeUtil.java
package com.code.liu; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; import java.awt.image.BufferedImage; import com.google.zxing.LuminanceSource; public class BufferedImageLuminanceSource extends LuminanceSource { private final BufferedImage image; private final int left; private final int top; public BufferedImageLuminanceSource(BufferedImage image) { this(image, 0, 0, image.getWidth(), image.getHeight()); } public BufferedImageLuminanceSource(BufferedImage image, int left, int top, int width, int height) { super(width, height); int sourceWidth = image.getWidth(); int sourceHeight = image.getHeight(); if (left + width > sourceWidth || top + height > sourceHeight) { throw new IllegalArgumentException( "Crop rectangle does not fit within image data."); } for (int y = top; y < top + height; y++) { for (int x = left; x < left + width; x++) { if ((image.getRGB(x, y) & 0xFF000000) == 0) { image.setRGB(x, y, 0xFFFFFFFF); // = white } } } this.image = new BufferedImage(sourceWidth, sourceHeight, BufferedImage.TYPE_BYTE_GRAY); this.image.getGraphics().drawImage(image, 0, 0, null); this.left = left; this.top = top; } public byte[] getRow(int y, byte[] row) { if (y < 0 || y >= getHeight()) { throw new IllegalArgumentException( "Requested row is outside the image: " + y); } int width = getWidth(); if (row == null || row.length < width) { row = new byte[width]; } image.getRaster().getDataElements(left, top + y, width, 1, row); return row; } public byte[] getMatrix() { int width = getWidth(); int height = getHeight(); int area = width * height; byte[] matrix = new byte[area]; image.getRaster().getDataElements(left, top, width, height, matrix); return matrix; } public boolean isCropSupported() { return true; } public LuminanceSource crop(int left, int top, int width, int height) { return new BufferedImageLuminanceSource(image, this.left + left, this.top + top, width, height); } public boolean isRotateSupported() { return true; } public LuminanceSource rotateCounterClockwise() { int sourceWidth = image.getWidth(); int sourceHeight = image.getHeight(); AffineTransform transform = new AffineTransform(0.0, -1.0, 1.0, 0.0, 0.0, sourceWidth); BufferedImage rotatedImage = new BufferedImage(sourceHeight, sourceWidth, BufferedImage.TYPE_BYTE_GRAY); Graphics2D g = rotatedImage.createGraphics(); g.drawImage(image, transform, null); g.dispose(); int width = getWidth(); return new BufferedImageLuminanceSource(rotatedImage, top, sourceWidth - (left + width), getHeight(), width); } }
package com.code.liu; 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.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; /** * 二维码工具类 * */ 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); 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; } /** * 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) 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)); } /** * 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) * @author lanyuan * Email: mmm333zzz520@163.com * @date 2013-12-11 上午10:16:36 * @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) throws Exception { QRCodeUtil.encode(content, imgPath, destPath, false); } /** * 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) throws Exception { QRCodeUtil.encode(content, null, destPath, needCompress); } /** * 生成二维码 * * @param content * 内容 * @param destPath * 存储地址 * @throws Exception */ public static void encode(String content, String destPath) throws Exception { QRCodeUtil.encode(content, null, destPath, false); } /** * 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); 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)); } public static void main(String[] args) throws Exception { String text = "http://www.cnblogs.com/qianxiaoruofeng/"; QRCodeUtil.encode(text, "c:/Users/Administrator/Desktop/liupeng/1.png", "c:/Users/Administrator/Desktop/liupeng/barcode", true); } }
生成不带logo 的二维码
程序代码
public static void main(String[] args) throws Exception {
String text = “http://www.cnblogs.com/qianxiaoruofeng/”;
QRCodeUtil.encode(text,””, “c:/Users/Administrator/Desktop/liupeng/barcode”,true);
}
运行这个测试方法，生成的二维码不带 logo , 样式如下:
有兴趣可以用手机扫描一下
生成带logo 的二维码
logo 可以用自己的头像，或者自己喜欢的一个图片都可以 , 采用如下代码
程序代码
public static void main(String[] args) throws Exception {
String text = “http://www.cnblogs.com/qianxiaoruofeng/“;
QRCodeUtil.encode(text, "c:/Users/Administrator/Desktop/liupeng/1.png", "c:/Users/Administrator/Desktop/liupeng/barcode", true);
}
唯一的区别是，在前面的基础上指定了logo 的地址，这里测试都用了C盘的图片文件
手机扫描二维码进入浅笑若风的博客。
版权声明：本文为qianxiaoruofeng原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。