程序员在上海之四

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今天主要分享下前段时间做微信二维码的一些问题,我们都知道二维码的生产可以放到java后端,也可以直接使用jQuery插件jquery.qrcode.min.js来简单实现。下面简单分享下两种方式:

    1、java代码生产二维码。

       具体实现如下:

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 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;
/**
 * 
 * @author ****
 *
 */
public class QRCodeUtil 
private static final String CHARSET = "utf-8";
private static final String FORMAT_NAME = "png";
// 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();


/**
 * 
 * @param content 二维码内容
 * @param imgPath 读取图片路径 放到二维码中间
 * @param destPath 存放图片路径
 * @param needCompress 
 * @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)+".png";
    //String file = "qrcode.png";//生成二维码的图片
//    ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));
    ImageIO.write(image, FORMAT_NAME, new File(destPath));



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://blog.csdn.net/tb176";
  //下面读取和生产图片路径自己设置
 QRCodeUtil.encode(text, "C:\\\\Users\\\\****\\\\Desktop\\\\qrcode\\\\share-wx.png", "C:\\\\Users\\\\****\\\\Desktop\\\\qrcode\\\\qrcode.png", true);



辅助类如下:

  

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

import com.google.zxing.LuminanceSource;
/**
 * 
 * @author ****
 *
 */
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);
    

以上是简单java实现二维码的生产,你可以通过扫描来查看是不是你想要的,下面来看下前段js怎么生成二维码的,这里我把工具改为WebStorm这样我们不需要每次都启动tomcat服了,它直接集成了这些功能,方便一些纯前端开发。最好参考《 点击打开链接》因为这里说的太简单明了了。

接下来是关于文本内容过长导致二维码识别度降低的问题,我们这是会选择吧长链接转为短链接,具体可以参考《点击打开链接》下面是个人的测试案例

	public static String Long2short(String url) throws IOException
			
			//生成短连接
			String reqUrl = "http://980.so/api.php?url="+ URLEncoder.encode(url,"UTF-8");
			logger.info("------转换之前的reqUrl="+reqUrl);
			Map<String,String> map = new HashMap<String,String>();
			String tinyUrl = GetRequest.getRequest(reqUrl,map);//http请求
			if(tinyUrl != null && tinyUrl.startsWith("http://980.so/"))
			
				url = tinyUrl;
			
			logger.info("------转换之后的url="+url);
			return url;
	

主函数也贴出来吧

public static void main(String[] args) throws IOException 
		String url = "https://www.baidu.com/s?ie=utf-8&f=3&rsv_bp=1&tn=monline_dg&wd=980.so&oq=js%E7%94%9F%E6%88%90%E4%BA%8C%E7%BB%B4%E7%A0%81&rsv_pq=9f72e3720004d0d6&rsv_t=4723nWbFLUDh%2BxsJxCGBAJ%2BIyt%2F3OrwBNiGnGzQOpohNKYSqP9%2FbfPxFd9RIHq9s6A&rqlang=cn&rsv_enter=1&inputT=7382&rsv_sug3=15&rsv_sug1=15&rsv_sug7=100&bs=js%E7%94%9F%E6%88%90%E4%BA%8C%E7%BB%B4%E7%A0%81";
		Long2short(url);
	


运行后,我们可以看到控制台结果

------转换之前的reqUrl=http://980.so/api.php?url=https%3A%2F%2Fwww.baidu.com%2Fs%3Fie%3Dutf-8%26f%3D3%26rsv_bp%3D1%26tn%3Dmonline_dg%26wd%3D980.so%26oq%3Djs%25E7%2594%259F%25E6%2588%2590%25E4%25BA%258C%25E7%25BB%25B4%25E7%25A0%2581%26rsv_pq%3D9f72e3720004d0d6%26rsv_t%3D4723nWbFLUDh%252BxsJxCGBAJ%252BIyt%252F3OrwBNiGnGzQOpohNKYSqP9%252FbfPxFd9RIHq9s6A%26rqlang%3Dcn%26rsv_enter%3D1%26inputT%3D7382%26rsv_sug3%3D15%26rsv_sug1%3D15%26rsv_sug7%3D100%26bs%3Djs%25E7%2594%259F%25E6%2588%2590%25E4%25BA%258C%25E7%25BB%25B4%25E7%25A0%2581
------转换之后的url=http://980.so/31pVn4
从结果,我们可以看出效果。这时候你可以吧转换之后的url复制到浏览器地址栏看看效果了,是不是一样的咯~

今天到此了,后续……






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