1 BufferedReader br = new BufferedReader(new InputStreamReader( 2                 new FileInputStream("userremain.log"))); 3 String msg = null; 4         String mail = null; 5         String newDateString=null;    //用户激活后第day天的存留率，先得到那天的日期 6         //要查看的某一天的新激活用户的存留率，先获得那天的所有的用户email 7         while (true) { 8             msg = br.readLine(); 9             if (msg == null) {10                 break; // 为空文件或者是读到最后，跳出循环11             }12             if ("".equals(msg))13                 continue;14             15 //            System.out.println("createTime:" + dateString);16             if (msg.contains("createTime:"+ dateString)) {17                 mail = msg.split(" ")[0].split(":")[1];18                 userSet.add(mail);19             }20         }21 22 //用户激活后第day天的存留率，先得到那天的日期23         newDateString=newDate(dateString, day);24         //获得某一天新激活的用户在第day天的留存用户25         while (true) {26             System.out.println("1111111111111111");27             msg = br.readLine();28             if (msg == null) {29                 break; // 为空文件或者是读到最后，跳出循环30             }31             if ("".equals(msg))32                 continue;33             System.out.println("222222222222222222222");34             System.out.println(msg.contains("activeTime:" + newDateString));35             if (msg.contains("activeTime:" + newDateString)) {36                 mail = msg.split(" ")[0].split(":")[1];37                 if(userSet.contains(mail)){38                     userRemainSet.add(mail);39                 }40             }41         }42         43         br.close();