Java实现二维码QRCode的编码和解码

周末试用下Android手机的二维码扫描软件，扫描了下火车票、名片等等，觉得非常不错很有意思的。当然Java也可以实现这些，现在就分享下如何简单用Java实现二维码中QRCode的编码和解码（可以手机扫描验证）。

涉及到的一些主要类库，方便大家下载：

• 编码 lib：Qrcode_swetake.jar （官网介绍 -- http://www.swetake.com/qr/index-e.html）
• 解码 lib：qrcode.jar （官网介绍 -- http://sourceforge.jp/projects/qrcode/）

后来发现一个更好的条形码和二维码的开源软件（ZXing），详细介绍见：http://sjsky.iteye.com/blog/1142177

【一】、编码：

QRCodeEncoderHandler.java

package <wbr>michael.qrcode;</wbr>

<wbr></wbr>

import <wbr>java.awt.Color;</wbr>

import <wbr>java.awt.Graphics2D;</wbr>

import <wbr>java.awt.image.BufferedImage;</wbr>

import <wbr>java.io.File;</wbr>

<wbr></wbr>

import <wbr>javax.imageio.ImageIO;</wbr>

<wbr></wbr>

import <wbr>com.swetake.util.Qrcode;</wbr>

<wbr></wbr>

<wbr></wbr>

public <wbr></wbr>class<wbr>QRCodeEncoderHandler <wbr>{</wbr></wbr>

<wbr></wbr>

public <wbr></wbr>void<wbr>encoderQRCode(String <wbr>content, <wbr>String <wbr>imgPath) <wbr>{</wbr></wbr></wbr></wbr></wbr>

try <wbr>{</wbr>

<wbr></wbr>

Qrcode <wbr>qrcodeHandler <wbr>= <wbr></wbr></wbr></wbr>new<wbr>Qrcode();</wbr>

qrcodeHandler.setQrcodeErrorCorrect('M');

qrcodeHandler.setQrcodeEncodeMode('B');

qrcodeHandler.setQrcodeVersion(7);

System.out.println(content);

byte[] <wbr>contentBytes<wbr>= <wbr>content.getBytes(</wbr></wbr></wbr>"gb2312");

<wbr></wbr>

BufferedImage <wbr>bufImg <wbr>= <wbr></wbr></wbr></wbr>new<wbr>BufferedImage(140, <wbr>140,</wbr></wbr>

BufferedImage.TYPE_INT_RGB);

<wbr></wbr>

Graphics2D <wbr>gs <wbr>= <wbr>bufImg.createGraphics();</wbr></wbr></wbr>

<wbr></wbr>

gs.setBackground(Color.WHITE);

gs.clearRect(0, <wbr>0, <wbr>140, <wbr>140);</wbr></wbr></wbr>

<wbr></wbr>

// <wbr>设定图像颜色 <wbr>&gt; <wbr>BLACK</wbr></wbr></wbr>

gs.setColor(Color.BLACK);

<wbr></wbr>

// <wbr>设置偏移量 <wbr>不设置可能导致解析出错</wbr></wbr>

int <wbr>pixoff <wbr> = <wbr>2;</wbr></wbr></wbr>

// <wbr>输出内容 <wbr>&gt; <wbr>二维码</wbr></wbr></wbr>

if <wbr>(contentBytes.</wbr>length<wbr>&gt; <wbr>0 <wbr>&amp;&amp; <wbr>contentBytes.</wbr></wbr></wbr></wbr>length<wbr>&lt; <wbr>120) <wbr>{</wbr></wbr></wbr>

boolean[][] <wbr> codeOut <wbr>= <wbr>qrcodeHandler.calQrcode(contentBytes);</wbr></wbr></wbr>

for <wbr>(</wbr>int<wbr>i <wbr>= <wbr>0; <wbr>i <wbr>&lt; <wbr>codeOut.</wbr></wbr></wbr></wbr></wbr></wbr>length;<wbr>i++) <wbr>{</wbr></wbr>

for <wbr>(</wbr>int<wbr>j <wbr>= <wbr>0; <wbr>j <wbr>&lt; <wbr>codeOut.</wbr></wbr></wbr></wbr></wbr></wbr>length;<wbr>j++) <wbr>{</wbr></wbr>

if <wbr>(codeOut[j][i])<wbr>{</wbr></wbr>

gs.fillRect(j <wbr>* <wbr>3 <wbr>+ <wbr>pixoff, <wbr> i <wbr>* <wbr>3 <wbr>+ <wbr>pixoff, <wbr>3, <wbr>3);</wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>

}

}

}

} <wbr></wbr>else<wbr>{</wbr>

System.err.println("QRCode<wbr>content <wbr>bytes <wbr>length <wbr>= <wbr>"</wbr></wbr></wbr></wbr></wbr>

+ <wbr>contentBytes.</wbr>length<wbr>+ <wbr></wbr></wbr>" <wbr>not <wbr>in <wbr>[ <wbr>0,120<wbr>]. <wbr>"</wbr></wbr></wbr></wbr></wbr></wbr>);

}

<wbr></wbr>

gs.dispose();

bufImg.flush();

<wbr></wbr>

File <wbr>imgFile <wbr>= <wbr></wbr></wbr></wbr>new<wbr>File(imgPath);</wbr>

<wbr></wbr>

// <wbr>生成二维码QRCode图片</wbr>

ImageIO.write(bufImg,<wbr></wbr>"png", <wbr>imgFile);</wbr>

<wbr></wbr>

} <wbr></wbr>catch<wbr>(Exception <wbr>e) <wbr>{</wbr></wbr></wbr>

e.printStackTrace();

}

<wbr></wbr>

}

<wbr></wbr>

<wbr></wbr>

public <wbr></wbr>static<wbr></wbr>void <wbr>main(String[] <wbr>args) <wbr>{</wbr></wbr></wbr>

String <wbr>imgPath <wbr>= <wbr></wbr></wbr></wbr>"D:/test/twocode/Michael_QRCode.png";

<wbr></wbr>

String <wbr>content <wbr>= <wbr></wbr></wbr></wbr>"Hello<wbr>大大、小小,welcome <wbr>to <wbr>QRCode!"</wbr></wbr></wbr>

+ <wbr></wbr>"\nMyblog<wbr>[ <wbr>http://sjsky.iteye.com <wbr>]"</wbr></wbr></wbr>

+ <wbr></wbr>"\nEMail <wbr> [ <wbr>chinajoebaby@hotmail.com <wbr>]"</wbr></wbr></wbr> <wbr>+<wbr></wbr></wbr>"\nTwitter <wbr>[ <wbr>@suncto <wbr>]"</wbr></wbr></wbr>;

<wbr></wbr>

QRCodeEncoderHandler <wbr>handler <wbr>= <wbr></wbr></wbr></wbr>new<wbr>QRCodeEncoderHandler();</wbr>

handler.encoderQRCode(content, <wbr>imgPath);</wbr>

<wbr></wbr>

System.out.println("encoder<wbr>QRcode <wbr>success"</wbr></wbr>);

}

}

运行后生成的二维码图片如下：

此时就可用手机的二维码扫描软件（本人用的：android 快拍二维码）来测试下，识别成功的截图如下：

喜欢的朋友可以下载后试一试，做一些名片或者自己喜欢的东西。当然Java也可以对二维码图片解码，具体看下面关于解码的内容。

【二】、解码：
QRCodeDecoderHandler.java

package <wbr>michael.qrcode;</wbr>

<wbr></wbr>

import <wbr>java.awt.image.BufferedImage;</wbr>

import <wbr>java.io.File;</wbr>

import <wbr>java.io.IOException;</wbr>

<wbr></wbr>

import <wbr>javax.imageio.ImageIO;</wbr>

<wbr></wbr>

import <wbr>jp.sourceforge.qrcode.QRCodeDecoder;</wbr>

import <wbr>jp.sourceforge.qrcode.data.QRCodeImage;</wbr>

import <wbr>jp.sourceforge.qrcode.exception.DecodingFailedException;</wbr>

<wbr></wbr>

<wbr></wbr>

public <wbr></wbr>class<wbr>QRCodeDecoderHandler <wbr>{</wbr></wbr>

<wbr></wbr>

<wbr></wbr>

public <wbr>String<wbr>decoderQRCode(String <wbr>imgPath) <wbr>{</wbr></wbr></wbr></wbr>

<wbr></wbr>

// <wbr>QRCode <wbr>二维码图片的文件</wbr></wbr>

File <wbr>imageFile <wbr>= <wbr></wbr></wbr></wbr>new<wbr>File(imgPath);</wbr>

<wbr></wbr>

BufferedImage <wbr>bufImg <wbr>= <wbr></wbr></wbr></wbr>null;

String <wbr>decodedData <wbr>= <wbr></wbr></wbr></wbr>null;

try <wbr>{</wbr>

bufImg <wbr>= <wbr>ImageIO.</wbr></wbr>read(imageFile);

<wbr></wbr>

QRCodeDecoder <wbr>decoder <wbr>= <wbr></wbr></wbr></wbr>new<wbr>QRCodeDecoder();</wbr>

decodedData <wbr>= <wbr></wbr></wbr>new<wbr>String(decoder.decode(</wbr>new<wbr>J2SEImage(bufImg)));</wbr>

<wbr></wbr>

// <wbr>try <wbr>{</wbr></wbr>

// <wbr>System.out.println(new <wbr>String(decodedData.getBytes("gb2312"),</wbr></wbr>

// <wbr>"gb2312"));</wbr>

// <wbr>} <wbr>catch <wbr>(Exception <wbr>e) <wbr> {</wbr></wbr></wbr></wbr></wbr>

// <wbr>// <wbr></wbr></wbr>TODO:<wbr>handle <wbr>exception</wbr></wbr>

// <wbr>}</wbr>

} <wbr></wbr>catch<wbr>(IOException <wbr>e) <wbr>{</wbr></wbr></wbr>

System.out.println("Error:<wbr>"</wbr> <wbr>+ <wbr>e.getMessage());</wbr></wbr>

e.printStackTrace();

} <wbr></wbr>catch<wbr>(DecodingFailedException <wbr>dfe) <wbr>{</wbr></wbr></wbr>

System.out.println("Error:<wbr>"</wbr> <wbr>+ <wbr>dfe.getMessage());</wbr></wbr>

dfe.printStackTrace();

}

return <wbr>decodedData;</wbr>

}

<wbr></wbr>

<wbr></wbr>

public <wbr></wbr>static<wbr></wbr>void <wbr>main(String[] <wbr>args) <wbr>{</wbr></wbr></wbr>

QRCodeDecoderHandler <wbr>handler <wbr>= <wbr></wbr></wbr></wbr>new<wbr>QRCodeDecoderHandler();</wbr>

String <wbr>imgPath <wbr>= <wbr></wbr></wbr></wbr>"d:/test/twocode/Michael_QRCode.png";

String <wbr>decoderContent <wbr>= <wbr>handler.decoderQRCode(imgPath);</wbr></wbr></wbr>

System.out.println("解析结果如下：");

System.out.println(decoderContent);

System.out.println("========decoder<wbr>success!!!"</wbr>);

}

<wbr></wbr>

class <wbr>J2SEImage<wbr></wbr></wbr>implements<wbr>QRCodeImage <wbr>{</wbr></wbr>

BufferedImage <wbr></wbr>bufImg;

<wbr></wbr>

public <wbr>J2SEImage(BufferedImage<wbr>bufImg) <wbr>{</wbr></wbr></wbr>

this.bufImg<wbr>= <wbr>bufImg;</wbr></wbr>

}

<wbr></wbr>

public <wbr></wbr>int<wbr>getWidth() <wbr>{</wbr></wbr>

return <wbr></wbr>bufImg.getWidth();

}

<wbr></wbr>

public <wbr></wbr>int<wbr>getHeight() <wbr>{</wbr></wbr>

return <wbr></wbr>bufImg.getHeight();

}

<wbr></wbr>

public <wbr></wbr>int<wbr>getPixel(</wbr>int<wbr>x, <wbr></wbr></wbr>int<wbr>y) <wbr>{</wbr></wbr>

return <wbr></wbr>bufImg.getRGB(x,<wbr>y);</wbr>

}

<wbr></wbr>

}

}

运行结果如下（解码出的内容和之前输入的内容一致）：

解析结果如下：
Hello 大大、小小,welcome to QRCode!
Myblog [ http://sjsky.iteye.com ]
EMail [ sjsky007@gmail.com ]
Twitter [ @suncto ]
========decoder success!!!

本文连接：http://sjsky.iteye.com/blog/1136934

P.S: Qrcode_swetake.jar 和 qrcode.jar 必须下载后导入工程后才可以运行程序。导入的方式为：

1.project右键-properties-Java Build path

2.操作图如下：

原创加借鉴： http://blog.sina.com.cn/s/blog_8ae46d1501011r1l.html