使用base64对图片的加密解密

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();
        }
    }      

}