java生成二维码

二维码现在已经到处都是了，下面是二维码的介绍
二维码，又称二维条码，二维条形码最早发明于日本，它是用某种特定的几何图形按一定规律在平面（二维方向上）分布的黑白相间的图形记录数据符号信息的，在代码编制上巧妙地利用构成计算机内部逻辑基础的“0”、“1”比特流的概念，使用若干个与二进制相对应的几何形体来表示文字数值信息，通过图象输入设备或光电扫描设备自动识读以实现信息自动处理。它具有条码技术的一些共性：每种码制有其特定的字符集；每个字符占有一定的宽度；具有一定的校验功能等。同时还具有对不同行的信息自动识别功能、及处理图形旋转变化等特点。

1.java这边的话生成二维码有很多开发的jar包如zxing,qrcode.q前者是谷歌开发的后者则是小日本开发的，这里的话我使用zxing的开发包来弄

2.先下载zxing开发包，这里用到的只是core那个jar包

3.使用zxing开发还需要一个类，代码如下

[java]
package org.lxh;
import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;
import java.io.File;
import java.io.OutputStream;
import java.io.IOException;
import java.awt.image.BufferedImage;


public final class MatrixToImageWriter {

   private static final int BLACK = 0xFF000000;
   private static final int WHITE = 0xFFFFFFFF;

   private MatrixToImageWriter() {}


   public static BufferedImage toBufferedImage(BitMatrix matrix) {
     int width = matrix.getWidth();
     int height = matrix.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, matrix.get(x, y) ? BLACK : WHITE);
       }
     }
     return image;
   }


   public static void writeToFile(BitMatrix matrix, String format, File file)
       throws IOException {
     BufferedImage image = toBufferedImage(matrix);
     if (!ImageIO.write(image, format, file)) {
       throw new IOException("Could not write an image of format " + format + " to " + file);
     }
   }


   public static void writeToStream(BitMatrix matrix, String format, OutputStream stream)
       throws IOException {
     BufferedImage image = toBufferedImage(matrix);
     if (!ImageIO.write(image, format, stream)) {
       throw new IOException("Could not write an image of format " + format);
     }
   }

}

package org.lxh;
import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;
import java.io.File;
import java.io.OutputStream;
import java.io.IOException;
import java.awt.image.BufferedImage;

public final class MatrixToImageWriter {

   private static final int BLACK = 0xFF000000;
   private static final int WHITE = 0xFFFFFFFF;

   private MatrixToImageWriter() {}


   public static BufferedImage toBufferedImage(BitMatrix matrix) {
     int width = matrix.getWidth();
     int height = matrix.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, matrix.get(x, y) ? BLACK : WHITE);
       }
     }
     return image;
   }


   public static void writeToFile(BitMatrix matrix, String format, File file)
       throws IOException {
     BufferedImage image = toBufferedImage(matrix);
     if (!ImageIO.write(image, format, file)) {
       throw new IOException("Could not write an image of format " + format + " to " + file);
     }
   }


   public static void writeToStream(BitMatrix matrix, String format, OutputStream stream)
       throws IOException {
     BufferedImage image = toBufferedImage(matrix);
     if (!ImageIO.write(image, format, stream)) {
       throw new IOException("Could not write an image of format " + format);
     }
   }

}
4.借助上面的类生成二维码

[java]
package org.lxh;

import java.io.File;
import java.util.Hashtable;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;

public class Test {

    /**
     * @param args
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        String text = "http://www.baidu.com";
        int width = 300;
        int height = 300;
        //二维码的图片格式
        String format = "gif";
        Hashtable hints = new Hashtable();
        //内容所使用编码
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
        BitMatrix bitMatrix = new MultiFormatWriter().encode(text,
                BarcodeFormat.QR_CODE, width, height, hints);
        //生成二维码
        File outputFile = new File("d:"+File.separator+"new.gif");
     &nb

补充：软件开发 , Java ,