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<File> list = new ArrayList<File>();
getAllFile(file,list);
backUp(list,dest);
}
//备份
private static void backUp(List<File> 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<File> 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，也希望大家多多支持编程网。
