Java 7如何操纵文件属性(一)

2014-11-24 07:53:51 · 作者: · 浏览: 2

Java 7如何操纵文件属性

作者:chszs,转载需注明。博客主页:http://blog.csdn.net/chszs

准备写点基础性的文章,Java 7已经出来很长一段时间了,但是很多Java程序员仍然停留在早期的Java 5或Java 6的基础上,对Java 7的新特性从未加以使用。本文介绍如何利用Java 7的NIO包读取文件属性以及修改文件属性。详情如下:

1、读取文件属性

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ReadFileAttribute1 {
	public static void main(String[] args){
		Path filePath = Paths.get("d:\\test.txt");
		try{
			BasicFileAttributes ra = Files.readAttributes(filePath, BasicFileAttributes.class);
			System.out.println("CREATION TIME:" + ra.creationTime());
			System.out.println("LAST ACCESS TIME:" + ra.lastAccessTime());
			System.out.println("FILE SIZE:" + ra.size());
			System.out.println("LAST MODIFIED:" + ra.lastModifiedTime());
			System.out.println("IS SYSBOLIC LINK:" + ra.isSymbolicLink());
			System.out.println("IS FOLDER:" + ra.isDirectory());
			System.out.println("IS FILE:" + ra.isRegularFile());
			
		}catch(IOException e){
			Logger.getLogger(ReadFileAttribute1.class.getName()).log(Level.SEVERE, null, e);
		}
	}
}
输出:
CREATION TIME:2013-04-09T05:45:30.685152Z
LAST ACCESS TIME:2013-08-12T00:30:43.19369Z
FILE SIZE:32
LAST MODIFIED:2013-12-10T13:35:08.438828Z
IS SYSBOLIC LINK:false
IS FOLDER:false
IS FILE:true

2、另一种读取文件属性的方法

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ReadFileAttribute2 {
	public static void main(String[] args){
		Path fp = Paths.get("D:\\test.txt");
		try{
			Files.getAttribute(fp, "basic:size");
			System.out.println("CREATION TIME:" + Files.getAttribute(fp, "basic:creationTime").toString());
			System.out.println("LAST ACCESS TIME:" + Files.getAttribute(fp, "basic:lastAccessTime").toString());
			System.out.println("FILE SIZE:" + Files.getAttribute(fp, "basic:size").toString());
			System.out.println("LAST MODIFIED:" + Files.getAttribute(fp, "basic:lastModifiedTime").toString());
			System.out.println("IS SYSBOLIC LINK:" + Files.getAttribute(fp, "basic:isSymbolicLink").toString());
			System.out.println("IS FOLDER:" + Files.getAttribute(fp, "basic:isDirectory").toString());
			System.out.println("IS FILE:" + Files.getAttribute(fp, "basic:isRegularFile").toString());
		}catch(IOException e){
			Logger.getLogger(ReadFileAttribute2.class.getName()).log(Level.SEVERE, null, e);
		}
		
	}
}

输出:

CREATION TIME:2013-04-09T05:45:30.685152Z
LAST ACCESS TIME:2013-08-12T00:30:43.19369Z
FILE SIZE:32
LAST MODIFIED:2013-12-10T13:35:08.438828Z
IS SYSBOLIC LINK:false
IS FOLDER:false
IS FILE:true

3、修改文件属性

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.attribute.BasicFileAttributes;
import java.nio.file.attribute.FileTime;
import java.util.logging.Level;
import java.util.logging.Logger;

public class UpdateFileAttribute1 {
	public static void main(String[] args){
		Path fp = Paths.get("D:\\test.txt");
		tr