import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

import java.io.*;

/**

 * @author lishupeng

 * @create 2017-05-06 下午 2:56

 **/

public class Base64Test {

    public static void main(String[] args) {

        String strImg = GetImageStr();

        System.out.println(strImg);

        GenerateImage(strImg);

    }

    //图片转化成base64字符串

    public static String GetImageStr() {//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

        String imgFile = "C:\\Users\\Administrator\\Desktop\\a\\1.png";//待处理的图片

        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();

        }

        //对字节数组Base64编码

        BASE64Encoder encoder = new BASE64Encoder();

        return encoder.encode(data);//返回Base64编码过的字节数组字符串

    }

    //base64字符串转化成图片

    public static boolean GenerateImage(String imgStr) {   //对字节数组字符串进行Base64解码并生成图片

        if (imgStr == null) //图像数据为空

            return false;

        BASE64Decoder decoder = new BASE64Decoder();

        try {

            //Base64解码

            byte[] b = decoder.decodeBuffer(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

            String imgFilePath = "d://222.jpg";//新生成的图片

            OutputStream out = new FileOutputStream(imgFilePath);

            out.write(b);

            out.flush();

            out.close();

            return true;

        } catch (Exception e) {

            return false;

        }

    }

import javax.imageio.stream.FileImageInputStream;

import javax.imageio.stream.FileImageOutputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.IOException;

/**

 * @author lishupeng

 * @create 2017-05-06 下午 3:48

 **/

public class Image2Byte {

    public static void main(String[] args){

        byte[] data = image2byte("C:\\Users\\Administrator\\Desktop\\a\\1.png");

        System.out.println(data.toString());

        byte2image(data,"d://222.jpg");

    }

    //图片到byte数组

    public static  byte[] image2byte(String path) {

        byte[] data = null;

        FileImageInputStream input = null;

        try {

            input = new FileImageInputStream(new File(path));

            ByteArrayOutputStream output = new ByteArrayOutputStream();

            byte[] buf = new byte[1024];

            int numBytesRead = 0;

            while ((numBytesRead = input.read(buf)) != -1) {

                output.write(buf, 0, numBytesRead);

            }

            data = output.toByteArray();

            output.close();

            input.close();

        } catch (FileNotFoundException ex1) {

            ex1.printStackTrace();

        } catch (IOException ex1) {

            ex1.printStackTrace();

        }

        return data;

    }

    //byte数组到图片

    public static void byte2image(byte[] data, String path) {

        if (data.length < 3 || path.equals("")) return;

        try {

            FileImageOutputStream imageOutput = new FileImageOutputStream(new File(path));

            imageOutput.write(data, 0, data.length);

            imageOutput.close();

            System.out.println("Make Picture success,Please find image in " + path);

        } catch (Exception ex) {

            System.out.println("Exception: " + ex);

            ex.printStackTrace();

        }

    }

    //byte数组到16进制字符串

    public String byte2string(byte[] data) {

        if (data == null || data.length <= 1) return "0x";

        if (data.length > 200000) return "0x";

        StringBuffer sb = new StringBuffer();

        int buf[] = new int[data.length];

        //byte数组转化成十进制

        for (int k = 0; k < data.length; k++) {

            buf[k] = data[k] < 0 ? (data[k] + 256) : (data[k]);

        }

        //十进制转化成十六进制

        for (int k = 0; k < buf.length; k++) {

            if (buf[k] < 16) sb.append("0" + Integer.toHexString(buf[k]));

            else sb.append(Integer.toHexString(buf[k]));

        }

        return "0x" + sb.toString().toUpperCase();

    }

}