import java.awt.image.BufferedImage;   
import java.io.ByteArrayInputStream;   
import java.io.ByteArrayOutputStream;   
import java.io.File;   
import java.io.IOException;   
  
import javax.imageio.ImageIO;   
  
import sun.misc.BASE64Decoder;   
import sun.misc.BASE64Encoder;   
  
public class TestImageBinary {   
    static BASE64Encoder encoder = new sun.misc.BASE64Encoder();   
    static BASE64Decoder decoder = new sun.misc.BASE64Decoder();   
       
    public static void main(String[] args) {   
        System.out.println(getImageBinary());   
           
        base64StringToImage(getImageBinary());   
    }   
       
    static String getImageBinary(){   
        File f = new File("c://20090709442.jpg");          
        BufferedImage bi;   
        try {   
            bi = ImageIO.read(f);   
            ByteArrayOutputStream baos = new ByteArrayOutputStream();   
            ImageIO.write(bi, "jpg", baos);   
            byte[] bytes = baos.toByteArray();   
               
            return encoder.encodeBuffer(bytes).trim();   
        } catch (IOException e) {   
            e.printStackTrace();   
        }   
        return null;   
    }   
       
    static void base64StringToImage(String base64String){   
        try {   
            byte[] bytes1 = decoder.decodeBuffer(base64String);   
               
            ByteArrayInputStream bais = new ByteArrayInputStream(bytes1);   
            BufferedImage bi1 =ImageIO.read(bais);   
            File w2 = new File("c://QQ.bmp");//可以是jpg,png,gif格式   
            ImageIO.write(bi1, "jpg", w2);//不管输出什么格式图片，此处不需改动   
        } catch (IOException e) {   
            e.printStackTrace();   
        }   
    }   
  
}