Question

java编写程序获取指定文件的最后修改时间

Answer 1

package com.xian.home2;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.List;

public class FileOperate {

/**
* @param args
*/
public static void main(String[] args) {
// FileOperate fo = new FileOperate();
// String filepath = "G:\\02";
// fo.getFileList(filepath);
getCreateTime();
}

public List<File> getFileList(String filepath) {

try {
File file = new File(filepath);
if (file.isDirectory()) {
String[] filelist = file.list();
for (int i = 0; i < filelist.length; i++) {
File Ifile = new File(filepath + "\\" + filelist[i]);
FileInputStream fis = new FileInputStream(Ifile);

long modifiedTime = Ifile.lastModified();
Date date=new Date(modifiedTime);
SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:MM");
String dd=sdf.format(date);
System.out.println("File name:" + Ifile.getName()
+ " \tFile size: "
+ (double) ((double) fis.available() / 1024 / 1024)
+ "M"+ " \tFile create Time: "+dd);

}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

return null;

}

/**
* 读取文件创建时间
*/
public static void getCreateTime(){
String filePath = "G:\\02\\123.txt";
String strTime = null;
try {
Process p = Runtime.getRuntime().exec("cmd /C dir "
+ filePath
+ "/tc" );
InputStream is = p.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line;
while((line = br.readLine()) != null){
if(line.endsWith(".txt")){
strTime = line.substring(0,17);
break;
}
}
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("创建时间 " + strTime);
//输出：创建时间 2009-08-17 10:21
}
/**
* 读取文件修改时间的方法1
*/
@SuppressWarnings("deprecation")
public static void getModifiedTime_1(){
File f = new File("C:\\test.txt");
Calendar cal = Calendar.getInstance();
long time = f.lastModified();
cal.setTimeInMillis(time);
//此处toLocalString()方法是不推荐的，但是仍可输出
System.out.println("修改时间[1] " + cal.getTime().toLocaleString());
//输出：修改时间[1] 2009-8-17 10:32:38
}

/**
* 读取修改时间的方法2
*/
public static void getModifiedTime_2(){
File f = new File("C:\\test.txt");
Calendar cal = Calendar.getInstance();
long time = f.lastModified();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
cal.setTimeInMillis(time);
System.out.println("修改时间[2] " + formatter.format(cal.getTime()));
//输出：修改时间[2] 2009-08-17 10:32:38
}

}

Answer 2

可以通过File流的lastModified方法获取到修改时间的。举例：
public static void getModifiedTime(){
File f = new File("C:\\test.txt");

Calendar cal = Calendar.getInstance();
long time = f.lastModified();
cal.setTimeInMillis(time);
System.out.println("修改时间： " + cal.getTime().toLocaleString());
}
结果：修改时间：2015-06-29 10:32:38

Answer 3

Calendar cal= new GregorianCalendar.setTimeInMillis( new File ("c:\1.txt").lastModified());

System.out.print(cal.toString());

Answer 4

 Path file = Paths.get("文件路径");
    BasicFileAttributes attrs = Files.readAttributes(file, BasicFileAttributes.class);
//之后在这个 attrs 变量中有个last开头的方法，你找一下就是了