Java实现定时备份文件教程

本文实例为大家分享了Java如何定时备份文件的具体实现代码，供大家参考，具体内容如下

程序思路：

1.空目录不备份，但非空目录都备份

2.源目录 source 要递归他下面所有的文件和目录 存入List

3.循环这个list，创建每个文件的目录

4.开始复制

以下代码实现了定时备份路径为e:\\a的文件，每30秒进行一次备份，时间可修改。

public class Test12 {
 
    public static void main(String[] args) throws InterruptedException {
 
        Timer t = new Timer();
        t.scheduleAtFixedRate(new MyTask(),new Date(),1000*30);
 
        for(int i = 0;i<10000;i++){
            Thread.sleep(1000);
            System.out.println("warning");
        }
 
 
    }
 
}
 
class MyTask extends TimerTask{
 
    static final String SOURCE = "e:\\a";
    static String DEST;
 
    @Override
    public void run() {
 
        Date d = new Date();
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss");
        DEST = "e:\\dest_" + df.format(d);
        File file = new File(SOURCE);
        File dest = new File(DEST);
 
        if(dest.exists()){
            deleteAll(dest);
        }
        System.out.println("创建备份目录？"+dest.mkdirs());
        List list = new ArrayList();
 
        getAllFile(file,list);
 
        backUp(list,dest);
    }
 
    //备份
    private static void backUp(List list, File dest) {
 
        if (list == null || list.size() <= 0)="" {="" return;="" }="" for="" (file="" f="" :="" list)="" {="" string="" fpath="f.getAbsolutePath();" 取出绝对路径="" e:\\a="" string="" newpath="fpath.replace(SOURCE," dest);="" system.out.println("对应的新路径"="" +="" newpath);="" file="" newfile="new" file(newpath);="" if="" (newfile.getparentfile().exists()="=" false)="" {="" system.out.println("创建"="" +="" newfile="" +="" "的父目录成功？"="" +="" newfile.getparentfile().mkdirs());="" }="" if="" (f.isfile())="" {="" copy(f,="" newfile);="" }="" }="" }="" 复制="" private="" static="" void="" copy(file="" infile,="" file="" outfile)="" {="" fileinputstream="" fis="null;" fileoutputstream="" fos="null;" boolean="" isflag="false;" try="" {="" fis="new" fileinputstream(infile);="" fos="new" fileoutputstream(outfile);="" byte[]="" bs="new" byte[1024];="" int="" length="-1;" while="" ((length="fis.read(bs))" !="-1)" {="" fos.write(bs,="" 0,="" length);="" }="" fos.flush();="" }="" catch="" (exception="" e)="" {="" e.printstacktrace();="" }="" finally="" {="" if="" (fos="" !="null)" {="" try="" {="" fos.close();="" }="" catch="" (ioexception="" e)="" {="" e.printstacktrace();="" }="" }="" if="" (fis="" !="null)" {="" try="" {="" fis.close();="" }="" catch="" (ioexception="" e)="" {="" e.printstacktrace();="" }="" }="" }="" }="" 递归获取原目录下所有的文件信息="" private="" static="" void="" getallfile(file="" source,=""> list) {
        if (source.isDirectory()) {
            //查看子目录 listFile()
            File[] fs = source.listFiles();
            if (fs != null && fs.length > 0) {
                //说明有子目录或子文件
                for (File ff : fs) {
                    getAllFile(ff, list);
                }
            }
 
        }
        list.add(source);
 
    }
 
    //递归删除
    private static void deleteAll(File f) {
        if (f.isDirectory()) {
            File[] fs = f.listFiles();
            if (fs != null && fs.length > 0) {
                for (File file : fs) {
                    deleteAll(file);
                }
            }
        }
        System.out.println(f + "删除成功？" + f.delete());
    }
 
}

再为大家补充一段：

import java.util.Calendar;
import java.util.Date;
import java.text.SimpleDateFormat;
import java.io.IOException;
import java.io.PrintStream;
  
public class Backup 
{
 public static void main(String[] args) 
 {
  Runtime runtime = Runtime.getRuntime();
  Calendar calendar = Calendar.getInstance();
  SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd_HHmmss");
  String currentTime = dateFormat.format(calendar.getTime());
  Process p = null;
  PrintStream print = null;
  StringBuilder buf = new StringBuilder();
  for(String a : args){
   buf.append(a);
   buf.append(" ");
  }
  String databases = buf.toString();
   
  try{
   p = runtime.exec("cmd /c mysqldump -uroot -p1234 -B "+databases+">"+currentTime+".sql.bak");
  }catch (IOException e){
   if( p != null ){
    p.destroy();
   }
   try{
    print = new PrintStream(currentTime+"_backup_err.log");
    dateFormat.applyPattern("yyyy-MM-dd HH:mm:ss");
    currentTime = dateFormat.format(calendar.getTime());
    print.println(currentTime+"  backup failed.");
    e.printStackTrace(print);
    print.flush();
   }catch (IOException e2){
  
   }finally{
    if(print!=null){
     print.close();
    }
   }
  }
 }
}

以上就是本文的全部内容，希望对大家的学习有所帮助