package com.net.util;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.servlet.http.HttpServletRequest;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
/**
 * 图片base64转码工具类
 * @author zhangdi
 *
 */
public class ImageBase64Util {
    
    /**
     * 图片转化成base64字符串
     * @param imgPath 图片路径
     * @return
     */
    public static String GetImageStr(String imgPath) {
        // 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 = imgPath;
        InputStream in = null;
        byte[] data = http://www.mamicode.com/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();
        // 返回Base64编码过的字节数组字符串
        return encoder.encode(data);
    }

    /**
     *  base64字符串转化成图片
     * @param imgStr  base64字符串
     * @param imgPath 图片路径
     * @return
     */
    public static boolean GenerateImage(String imgStr,String imgPath,HttpServletRequest request) {
        //获得物理路径webapp所在路径  
        String pathRoot = request.getSession().getServletContext().getRealPath("");
        // 对字节数组字符串进行Base64解码并生成图片
        if (imgStr == null)
            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;
                }
            }
            // 生成新的图片
            String imgFilePath =pathRoot+imgPath;
            OutputStream out = new FileOutputStream(imgFilePath);
            out.write(b);
            out.flush();
            out.close();
            return true;
        } catch (Exception e) {
            return false;
        }
    }
}