JAVA实现模拟导入数据/上传文件进度条

package com.progress.servlet; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class DataServlet extends HttpServlet { private static final long serialVersionUID = -5245994119484470538L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); response.setContentType("text/html;charset=utf-8;"); String option = request.getParameter("option"); if (option.equals("progress")) { this.progress(request, response); } } /** * 模拟数据导入 * * @param request * @param response * @throws ServletException * @throws IOException */ public void progress(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Object value = request.getSession().getAttribute("pr"); int max; int count; if (value == null) { // 设置数据总量，如上传文件则获取文件大小，导入数据则获取数据条数 max = 10000; } else { max = Integer.parseInt(value.toString()); } // 设置最大文件数 if (max > 0) { // 导入了多少数据就减少多少 count = max--; // 拼接json。返回给前端 String json = "{'max':'" + max + "',count:'" + count + "'}"; response.getWriter().print(json); request.getSession().setAttribute("pr", count); } } }