一步一步教你用 java 生成二维码

来源:互联网 发布:mac桌面不显示u盘图标 编辑:程序博客网 时间:2024/05/01 12:44

一步一步用java设计生成二维码

在物联网的时代,二维码是个很重要的东西了,现在无论什么东西都要搞个二维码标志,唯恐落伍,就差人没有用二维码识别了。也许有一天生分证或者户口本都会用二维码识别了。今天心血来潮,看见别人都为自己的博客添加了二维码,我也想搞一个测试一下.

主要用来实现两点:

1. 生成任意文字的二维码.

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。

首先得下载 zxing.jar 包, 我这里用的是3.0 版本的core

下载地址: 现在已经迁移到了github: https://github.com/zxing/zxing/wiki/Getting-Started-Developing,

当然你也可以从maven仓库下载jar : 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 , 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


 

关键代码在于:BufferedImageLuminanceSource.java QRCodeUtil.java , 其中测试的main 方法位于QRCodeUtil.java 中。

BufferedImageLuminanceSource.java程序代码:

                                                                                                                                                                                                                   package qrcodesoft;

<span style="background-color: rgb(255, 255, 255);">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);    }}</span>

QRCodeUtil.java的程序代码:

                                                                                                                                                                                                                         

<span style="background-color: rgb(255, 255, 255);">package qrcodesoft;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;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();    }       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;        }        BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(                image);        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(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.dans88.com.cn";        QRCodeUtil.encode(text, "d:/MyWorkDoc/my180.jpg", "d:/MyWorkDoc", true);    }   }</span>


生成不带logo 的二维码

程序代码

 

<span style="background-color: rgb(255, 255, 255);">public static void main(String[] args) throws Exception {        String text = "http://www.dans88.com.cn";        QRCodeUtil.encode(text,"","d:/MyWorkDoc",true);</span>

 

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

 

<span style="background-color: rgb(255, 255, 255);">public static void main(String[] args) throws Exception {        String text = "http://www.dans88.com.cn";        QRCodeUtil.encode(text, "d:/MyWorkDoc/my180.jpg", "d:/MyWorkDoc", true);    }</span>

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





用手机扫描,能出现要出现的文字,点击就进入自己的网站,看起来还不错, 整个源代码,提供在下载测试:

java barcode sample

本文转载于:http://blog.sina.com.cn/s/blog_5a6efa330102v1lb.html

 

1 0
原创粉丝点击