电子商务网站设计与开发案例教程电子贺卡制作软件app

数据越积越多，过于冗余；数据库定期删除指定时间前的数据；文件生成的删除指定时间前端文件

SFTP文件定期删除

java sftp 定时清理指定文件中固定时间

• 依赖

<!-- ftp文件上传/下载Jar包 -->
<dependency><groupId>com.jcraft</groupId><artifactId>jsch</artifactId><version>0.1.54</version>
</dependency>

• 代码

import com.jcraft.jsch.*;import java.util.Vector;/*** java sftp 定时清理指定文件中固定时间*/
public class SftpCleanup {public static void main(String[] args) throws JSchException {String host = "127.0.0.1"; // SFTP主机地址int port = 22; // SFTP端口号String username = "xxx"; // SFTP登录用户名String password = "xxxx"; // SFTP登录密码Session session = null;ChannelSftp channelSftp = null;try {JSch jsch = new JSch();// 创建Session对象session = jsch.getSession(username, host, port);session.setPassword(password);session.setConfig("StrictHostKeyChecking", "no");session.connect();// 打开ChannelSftp通道channelSftp = (ChannelSftp) session.openChannel("sftp");channelSftp.connect();// 设置删除目标文件的路径及过期时间（单位为分钟）// 默认为当前日期之前的24小时内的文件将被删除//long expireTimeInMinutes = 60 * 24;long currentTimeMillis = System.currentTimeMillis();//long threeMonthsAgoInMillis = currentTimeMillis - 2 * 7 * 60 * 60 * 1000L; // 当前时间减去N个天的毫秒数long threeMonthsAgoInMillis = currentTimeMillis - 90 * 24 * 60 * 60 * 1000L; // 当前时间减去3个月(3*30)的毫秒数String targetPath = "/data/file/hi/"; // 目标文件路径Vector<ChannelSftp.LsEntry> fileList = channelSftp.ls(targetPath); // 要清理的目标文件所在路径for (ChannelSftp.LsEntry entry : fileList) {if (!entry.getAttrs().isDir()) {long fileCreationTime = entry.getAttrs().getMTime() * 1000L;printTimeDifference(true, fileCreationTime, threeMonthsAgoInMillis);if (fileCreationTime < threeMonthsAgoInMillis) {channelSftp.rm(targetPath + entry.getFilename()); // 删除符合条件的文件System.out.println("成功删除文件：" + targetPath + entry.getFilename());} else {System.out.println("未到达过期时间，不处理文件：" + targetPath + entry.getFilename());}}}} catch (JSchException | SftpException e) {e.printStackTrace();} finally {// 关闭ChannelSftp通道和会话if (channelSftp != null && channelSftp.isConnected()) {channelSftp.disconnect();}if (session != null && session.isConnected()) {session.disconnect();}}}/*** 打印计算时间差** @param fileCreationTime  sftpFileTime* @param presetsTimeMillis threeMonthsAgoInMillis*/private static void printTimeDifference(boolean debugger, long fileCreationTime, long presetsTimeMillis) {// 计算两者之间的差值（单位：微秒）long diffMicroseconds = (fileCreationTime - presetsTimeMillis);// 将差值转化为小时、分钟和秒int days = (int) (diffMicroseconds / (24 * 60 * 60 * 1000));int hours = (int) (diffMicroseconds / (60 * 60 * 1000));int minutes = (int) ((diffMicroseconds % (60 * 60 * 1000)) / (60 * 1000));int seconds = (int) ((diffMicroseconds % (60 * 1000)) / 1000);// 输出结果//System.out.println("差值为 " + diffMicroseconds + " 微秒");if (debugger) {System.out.println("差值为 " + days + " 天 " + hours + " 小时 " + minutes + " 分钟 " + seconds + " 秒");}}
}

mysql保存N个月的数据

mysql中保存3个月的数据，当超过3个月之后定时清除3个月之前的数据

• Mysql

-- 至少保留一个月数据量 delete from table_name
SELECT DATE_SUB(NOW(), INTERVAL 1 MONTH);
select count(*) from table_name where create_time < DATE_SUB(NOW(), INTERVAL 1 MONTH);

• Api

    public void deleteCustomerTouch(String monthNum) {if (StringUtils.isBlank(monthNum)) {monthNum = YsConst.Month.THREE;}//值不为空，且值为数值，且值要大于等于1if (NumberUtil.isNumber(monthNum) && NumberUtil.parseInt(monthNum) >= 1) {apiService.deleteByTime(monthNum);} else {logger.error("【apiService】其他的，参数错误 monthNum={}", monthNum);}}

• Mapper

    <!-- 小于等于 --><delete id="deleteByTime">delete from table_name where create_time &lt;= DATE_SUB(NOW(), INTERVAL #{monthNum} MONTH)</delete>