import java.io.FileInputStream;

 import java.io.FileOutputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStream;

 import org.apache.commons.codec.binary.Base64;

 /**

  * 将图片转换为Base64<br>

  * 将base64编码字符串解码成img图片

  * @创建时间 2015-06-01 15:50

  *

  */

 public class Img2Base64Util {

     public static void main(String[] args) {

         String imgFile = "d:\\3.jpg";//待处理的图片

         String imgbese=getImgStr(imgFile);

         System.out.println(imgbese.length());

         System.out.println(imgbese);

         String imgFilePath = "d:\\332.jpg";//新生成的图片

         generateImage(imgbese,imgFilePath);

     }

     /**

      * 将图片转换成Base64编码

      * @param imgFile 待处理图片

      * @return

      */

     public static String getImgStr(String imgFile){

         //将图片文件转化为字节数组字符串，并对其进行Base64编码处理

         InputStream in = null;

         byte[] data = null;

         //读取图片字节数组

         try

         {

             in = new FileInputStream(imgFile);

             data = new byte[in.available()];

             in.read(data);

             in.close();

         }

         catch (IOException e)

         {

             e.printStackTrace();

         }

         return new String(Base64.encodeBase64(data));

     }

     /**

      * 对字节数组字符串进行Base64解码并生成图片

      * @param imgStr 图片数据

      * @param imgFilePath 保存图片全路径地址

      * @return

      */

     public static boolean generateImage(String imgStr,String imgFilePath){

         //

         if (imgStr == null) //图像数据为空

             return false;

         try

         {

             //Base64解码

             byte[] b = Base64.decodeBase64(imgStr);

             for(int i=0;i<b.length;++i)

             {

                 if(b[i]<0)

                 {//调整异常数据

                     b[i]+=256;

                 }

             }

             //生成jpeg图片

             OutputStream out = new FileOutputStream(imgFilePath);

             out.write(b);

             out.flush();

             out.close();

             return true;

         }

         catch (Exception e)

         {

             return false;

         }

     }

 }

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