Java 随笔记

java实现图片与base64字符串之间的转换

http://blog.csdn.net/hfhwfw/article/details/5544408

package cn.com;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

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 = "d://test.jpg";//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);

//如果不是对图片的质量有硬性的要求，不建议使用这种方式去异常

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

if (b[i] < 0) {

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;

}

}

//计算距离今天结束还有多少秒

Calendar todayEnd = Calendar.getInstance();

long nowTime = todayEnd.getTime().getTime()/1000;

System.out.println(todayEnd.getTime().getTime()/1000);

todayEnd.set(Calendar.HOUR_OF_DAY, 24);

todayEnd.set(Calendar.MINUTE, 0);

todayEnd.set(Calendar.SECOND, 0);

todayEnd.set(Calendar.MILLISECOND, 0);

long diff = todayEnd.getTime().getTime()/1000 - nowTime;

参考文章 http://blog.csdn.net/f1024042400/article/details/50826374

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