一步一步教你用 java&n…

写的真好。。拜读

原文地址：java 生成二维码">一步一步教你用 java 生成二维码作者：浪友dans

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包

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

 

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

BufferedImageLuminanceSource.java程序代码：

package qrcodesoft;


import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;

import com.google.zxing.LuminanceSource;

public class BufferedImageLuminanceSource extends LuminanceSource{
    privatefinal BufferedImage image;
    privatefinal int left;
    privatefinal int top;

    publicBufferedImageLuminanceSource(BufferedImage image) {
       this(image,0, 0, image.getWidth(), image.getHeight());
    }

    publicBufferedImageLuminanceSource(BufferedImage image, int left,
          int top, intwidth, int height) {
       super(width,height);

       intsourceWidth = image.getWidth();
       intsourceHeight = image.getHeight();
       if (left +width > sourceWidth || top + height > sourceHeight) {
          throw newIllegalArgumentException(
                "Croprectangle 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;
    }

   
    publicbyte[] getRow(int y, byte[] row) {
       if (y < 0|| y >= getHeight()) {
          throw newIllegalArgumentException(
                "Requestedrow is outside the image: " + y);
       }
       int width =getWidth();
       if (row ==null || row.length < width) {
          row = newbyte[width];
       }
      image.getRaster().getDataElements(left, top + y, width, 1,row);
       returnrow;
    }

   
    publicbyte[] getMatrix() {
       int width =getWidth();
       int height =getHeight();
       int area =width * height;
       byte[]matrix = new byte[area];
      image.getRaster().getDataElements(left, top, width, height,matrix);
       returnmatrix;
    }

   
    publicboolean isCropSupported() {
       returntrue;
    }

   
    publicLuminanceSource crop(int left, int top, int width, int height){
       return newBufferedImageLuminanceSource(image, this.left + left,
             this.top +top, width, height);
    }

   
    publicboolean isRotateSupported() {
       returntrue;
    }

   
    publicLuminanceSource rotateCounterClockwise() {
       intsourceWidth = image.getWidth();
       intsourceHeight = 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 newBufferedImageLuminanceSource(rotatedImage, top,
             sourceWidth- (left + width), getHeight(), width);
    }
}

QRCodeUtil.java的程序代码：

packageqrcodesoft;


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 {

    privatestatic final String CHARSET = "utf-8";
    privatestatic final String FORMAT_NAME = "JPG";
    //二维码尺寸
    privatestatic final int QRCODE_SIZE = 300;
    //LOGO宽度
    privatestatic final int WIDTH = 60;
    //LOGO高度
    privatestatic final int HEIGHT = 60;

    privatestatic BufferedImage createImage(String content, StringimgPath,
          booleanneedCompress) throws Exception {
       Hashtablehints = new Hashtable();
      hints.put(EncodeHintType.ERROR_CORRECTION,ErrorCorrectionLevel.H);
      hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
      hints.put(EncodeHintType.MARGIN, 1);
       BitMatrixbitMatrix = 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)) {
          returnimage;
       }
       //插入图片
      QRCodeUtil.insertImage(image, imgPath, needCompress);
       returnimage;
    }

   
    privatestatic void insertImage(BufferedImage source, String imgPath,
          booleanneedCompress) 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
       Graphics2Dgraph = 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();
    }

   
    publicstatic void encode(String content, String imgPath, StringdestPath,
          booleanneedCompress) throws Exception {
      BufferedImage image = QRCodeUtil.createImage(content,imgPath,
            needCompress);
      mkdirs(destPath);
       String file= new Random().nextInt(99999999)+".jpg";
      ImageIO.write(image, FORMAT_NAME, newFile(destPath+"/"+file));
    }

   
    publicstatic void mkdirs(String destPath) {
       File file=newFile(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();
       }
    }

   
    publicstatic void encode(String content, String imgPath, StringdestPath)
          throwsException {
      QRCodeUtil.encode(content, imgPath, destPath, false);
    }

   
    publicstatic void encode(String content, String destPath,
          booleanneedCompress) throws Exception {
      QRCodeUtil.encode(content, null, destPath, needCompress);
    }

   
    publicstatic void encode(String content, String destPath) throwsException {
      QRCodeUtil.encode(content, null, destPath, false);
    }

   
    publicstatic void encode(String content, String imgPath,
          OutputStreamoutput, boolean needCompress) throws Exception {
      BufferedImage image = QRCodeUtil.createImage(content,imgPath,
            needCompress);
      ImageIO.write(image, FORMAT_NAME, output);
    }

   
    publicstatic void encode(String content, OutputStream output)
          throwsException {
      QRCodeUtil.encode(content, null, output, false);
    }

   
    publicstatic String decode(File file) throws Exception {
      BufferedImage image;
       image =ImageIO.read(file);
       if (image ==null) {
          returnnull;
       }
      BufferedImageLuminanceSource source = newBufferedImageLuminanceSource(
            image);
       BinaryBitmapbitmap = new BinaryBitmap(new HybridBinarizer(source));
       Resultresult;
       Hashtablehints = new Hashtable();
      hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
       result = newMultiFormatReader().decode(bitmap, hints);
       StringresultStr = result.getText();
       returnresultStr;
    }

   
    publicstatic String decode(String path) throws Exception {
       returnQRCodeUtil.decode(new File(path));
    }
   
   
    publicstatic void main(String[] args) throws Exception {
       String text= "http://www.dans88.com.cn";
      QRCodeUtil.encode(text, "d:/MyWorkDoc/my180.jpg", "d:/MyWorkDoc",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.dans88.com.cn";
       QRCodeUtil.encode(text,"","d:/MyWorkDoc",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.dans88.com.cn";
      QRCodeUtil.encode(text, "d:/MyWorkDoc/my180.jpg", "d:/MyWorkDoc",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

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