IO 文档操作案列

1：使用IO实现文件的移动

　　　　

package com.IO;



import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.RandomAccessFile;



public class Move {

    public static void main(String[] args) {

        File file=new File("F:/zhou/zhou.txt");

        try {

            RandomAccessFile rdf=new RandomAccessFile(file,"rw");

            FileInputStream in=new FileInputStream(file);

            byte[] bytes=new byte[1024];

            in.read(bytes);

            in.close();

            

            

            RandomAccessFile w=new RandomAccessFile(file,"rw");



            FileOutputStream os=new FileOutputStream("d:/w.txt");

            os.write(bytes);

            os.close();

            

        } catch (Exception e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }



    }



}

2：创建文件夹 以及文件  并实现读写

View Code

import java.io.File;

import java.io.FileInputStream;



import java.io.FileOutputStream;

import java.io.IOException;



public class Test {

    public static void main(String[] args) {

        File file=new File("F:/zhou/zhou.txt");

        //创建文件夹

    /*    if(!file.exists()){

            file.mkdir();

        }

        */

            try {

                //创建文件

                file.createNewFile();

            } catch (IOException e) {

                // TODO Auto-generated catch block

                e.printStackTrace();

            }

    

        try {

            

            FileOutputStream os=new FileOutputStream(file);

            String str="你好！！我是张三";

            os.write(str.getBytes());

            os.close();

            

            FileInputStream is=new FileInputStream(file);

            byte[] bytes=new byte[1024];

            int red=is.read(bytes);

            System.out.println(new String(bytes,0,red));//指定长度的数据

        } catch (Exception e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

}

3：显示某个目录的所有文件夹

ViewFile

package com.IO;



import java.io.File;



public class ViewFile {

    public static void main(String[] args) {

        File file=new File("F:");

        File[] fileList=file.listFiles();

        for(int i=0;i<fileList.length;i++){

            if(fileList[i].isDirectory()){

                System.out.println("["+fileList[i].getName()+"]");

            }

            else{

                System.out.println("fileList[i].getName()");

            }

        }

    }



}

4：

import java.io.*;



public class WR {

    public static void main(String []args) throws Exception{

        File f=new File("d:"+File.separator+"demo.doc");

        Writer out=new FileWriter(f);

        out.write("hello word");

        out.close();

        Reader reader=new FileReader(f);

        char c[]=new char[1024];

        int len=reader.read(c);

        System.out.println(new String(c,0,len));

        out.close();

        reader.close();

    }

}