Detailed explanation of the basic usage of File class in Java file programming
下面小编就为大家带来一篇Java文件(io)编程_基于File类的基本用法(必看篇)。小编觉得挺不错的,现在就分享给大家,也给大家做个参考。一起跟随小编过来看看吧
1、首先了解文件流的相关概念:
2、文件File类的基本用法
public class Demo_1 { public static void main(String[] args) { //创建一个文件对象 File f=new File("e:\\aa.txt"); //得到文件的路径 System.out.println("文件路径:"+f.getAbsolutePath()); //得到文件的大小,字节数 System.out.println("文件大小:"+f.length()); System.out.println("文件可读:"+f.canRead()); //创建文件夹 File f3=new File("e:\\ff"); if(!f3.isDirectory()){ //创建 f3.mkdir(); }else{ System.out.println("文件夹已存在"); } //创建文件 File f2=new File("e:\\ff\\hsp.txt"); if(!f2.exists()){ //可以创建 try { f2.createNewFile(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } }else{ System.out.print("有文件,不能创建"); } //列出一个文件夹下面的所有文件 File f4=new File("e://安装包下载"); //引号下也可写成e:/ff if(f4.isDirectory()){ File lists[]=f4.listFiles(); for(int i=0;i<lists.length;i++){ System.out.println("文件名:"+lists[i].getName()); } } } }
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