java实现二维码

说起二维码，微信好像最先启用，随后各类二维码就开始流行起来了。那什么是二维码呢。

1.什么是二维码？百度一下即可

http://baike.baidu.com/view/132241.htm?fr=aladdin

2.java开发二维码？

　　2.1：首先导入：此包

　　下载地址：http://pan.baidu.com/s/1jGJwPwU

　　2.2:java类

 1 import java.awt.image.BufferedImage;
 2
 3 /**
 4  * Encapsulates custom configuration used in methods of {@link MatrixToImageWriter}.
 5  */
 6 public final class MatrixToImageConfig {
 7
 8   public static final int BLACK = 0xFF000000;
 9   public static final int WHITE = 0xFFFFFFFF;
10
11   private final int onColor;
12   private final int offColor;
13
14   /**
15    * Creates a default config with on color {@link #BLACK} and off color {@link #WHITE}, generating normal
16    * black-on-white barcodes.
17    */
18   public MatrixToImageConfig() {
19     this(BLACK, WHITE);
20   }
21
22   /**
23    * @param onColor pixel on color, specified as an ARGB value as an int
24    * @param offColor pixel off color, specified as an ARGB value as an int
25    */
26   public MatrixToImageConfig(int onColor, int offColor) {
27     this.onColor = onColor;
28     this.offColor = offColor;
29   }
30
31   public int getPixelOnColor() {
32     return onColor;
33   }
34
35   public int getPixelOffColor() {
36     return offColor;
37   }
38
39   int getBufferedImageColorModel() {
40     // Use faster BINARY if colors match default
41     return onColor == BLACK && offColor == WHITE ? BufferedImage.TYPE_BYTE_BINARY : BufferedImage.TYPE_INT_RGB;
42   }
43
44 }

 1 import java.awt.image.BufferedImage;
 2 import java.io.File;
 3 import java.io.IOException;
 4 import java.io.OutputStream;
 5
 6 import javax.imageio.ImageIO;
 7
 8 import com.google.zxing.common.BitMatrix;
 9 public class MatrixToImageWriter {
10      private static final int BLACK = 0xFF000000;
11        private static final int WHITE = 0xFFFFFFFF;
12
13        private MatrixToImageWriter() {}
14
15
16        public static BufferedImage toBufferedImage(BitMatrix matrix) {
17          int width = matrix.getWidth();
18          int height = matrix.getHeight();
19          BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
20          for (int x = 0; x < width; x++) {
21            for (int y = 0; y < height; y++) {
22              image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE);
23            }
24          }
25          return image;
26        }
27
28
29        public static void writeToFile(BitMatrix matrix, String format, File file)
30            throws IOException {
31          BufferedImage image = toBufferedImage(matrix);
32          if (!ImageIO.write(image, format, file)) {
33            throw new IOException("Could not write an image of format " + format + " to " + file);
34          }
35        }
36
37
38        public static void writeToStream(BitMatrix matrix, String format, OutputStream stream)
39            throws IOException {
40          BufferedImage image = toBufferedImage(matrix);
41          if (!ImageIO.write(image, format, stream)) {
42            throw new IOException("Could not write an image of format " + format);
43          }
44        }
45 }

test类：

 1 import java.io.File;
 2 import java.util.Hashtable;
 3
 4 import com.google.zxing.BarcodeFormat;
 5 import com.google.zxing.EncodeHintType;
 6 import com.google.zxing.MultiFormatWriter;
 7 import com.google.zxing.common.BitMatrix;
 8
 9 public class Test {
10
11     public static void main(String[] args) throws Exception{
12         String text = "http://www.baidu.com";//二维码的内容
13         int width = 400;
14         int height = 400;
15         String format = "png";
16         Hashtable hints= new Hashtable();
17         hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
18         BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height,hints);
19         File outputFile = new File("E:/codeImg");
20         MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile);
21         System.out.println("It is ok!");
22
23     }
24 }

以上用的是一个谷歌提供的开源框架首先的，呵呵。。。站在巨人的肩膀上使用....

效果图：