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

　　

import java.awt.image.BufferedImage;

/**
 * Encapsulates custom configuration used in methods of {@link MatrixToImageWriter}.
 */
public final class MatrixToImageConfig {

  public static final int BLACK = 0xFF000000;
  public static final int WHITE = 0xFFFFFFFF;
  
  private final int onColor;
  private final int offColor;

  /**
   * Creates a default config with on color {@link #BLACK} and off color {@link #WHITE}, generating normal
   * black-on-white barcodes.
   */
  public MatrixToImageConfig() {
    this(BLACK, WHITE);
  }

  /**
   * @param onColor pixel on color, specified as an ARGB value as an int
   * @param offColor pixel off color, specified as an ARGB value as an int
   */
  public MatrixToImageConfig(int onColor, int offColor) {
    this.onColor = onColor;
    this.offColor = offColor;
  }

  public int getPixelOnColor() {
    return onColor;
  }

  public int getPixelOffColor() {
    return offColor;
  }

  int getBufferedImageColorModel() {
    // Use faster BINARY if colors match default
    return onColor == BLACK && offColor == WHITE ? BufferedImage.TYPE_BYTE_BINARY : BufferedImage.TYPE_INT_RGB;
  }

}

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;

import javax.imageio.ImageIO;

import com.google.zxing.common.BitMatrix;
public 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);
         }
       }
}

test类：

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.common.BitMatrix;

public class Test {

    public static void main(String[] args) throws Exception{
        String text = "http://www.baidu.com";//二维码的内容
        int width = 400;  
        int height = 400;  
        String format = "png";    
        Hashtable hints= new Hashtable();  
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");  
        BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height,hints);  
        File outputFile = new File("E:/codeImg");  
        MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile); 
        System.out.println("It is ok!");

    }
}

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：