<%@ page language="java" pageEncoding="UTF-8" %>
 <jsp:directive.page import="sun.misc.BASE64Encoder"/>
 <jsp:directive.page import="java.io.InputStream"/>
 <jsp:directive.page import="java.io.File"/>
 <%
  File file = new File(this.getServletContext().getRealPath("cookie.gif"));
  
  // 二进制数组
  byte[] binary = new byte[(int)file.length()];
  
  // 从图片文件读取二进制数据. 
  InputStream ins = this.getServletContext().getResourceAsStream(file.getName());
  ins.read(binary);
  ins.close();
  
  // BASE64 编码
  String content = BASE64Encoder.class.newInstance().encode(binary);
  
  // 包含二进制数据的 Cookie
  Cookie cookie = new Cookie("file", content);
   
  // 将 Cookie 发送到客户端 
  response.addCookie(cookie);
 %>
 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 <html>
 <head>
 <title>Cookie Encoding</title>
 </head>
 <body>
 从 Cookie 中获取到的二进制图片：<img src="base64_decode.jsp" /> <br/>
 <textarea id='cookieArea' style='width:100%; height:200px; '></textarea>
 <script type="text/javascript">cookieArea.value=document.cookie;</script>
 </body>
 </html>
<%@ page language="java" pageEncoding="UTF-8" %>
 <jsp:directive.page import="sun.misc.BASE64Decoder"/>
 <jsp:directive.page trimDirectiveWhitespaces="true"/>
 <%
  // 清除输出
  out.clear();
  
  for(Cookie cookie : request.getCookies()){
  
   if(cookie.getName().equals("file")){
   
    // 从 Cookie 中取二进制数据
    byte[] binary = BASE64Decoder.class.newInstance().decodeBuffer(cookie.getValue().replace(" ", ""));
    
    // 设置内容类型为 gif 图片
    response.setHeader("Content-Type", "image/gif");
    response.setHeader("Content-Disposition", "inline;filename=cookie.gif");
    response.setHeader("Connection", "close");
    
    // 设置长度
    response.setContentLength(binary.length);
    
    // 输出到客户端
    response.getOutputStream().write(binary);
    response.getOutputStream().flush();
    response.getOutputStream().close();
    
    return;
   }
  }
  
 %>