iodemo.java~9~

来自「java 使用FileStream 复制文件」· JAVA~9~ 代码 · 共 53 行

package day7;
import java.io.*;
public class IODemo {
    public static void main(String[] args) {
        //writeFile();
        readFile();
    }
    public static void readFile()
    {
        File f=new File("abc.txt");
        if(!f.exists())
        {
            System.out.println("file not found!");
            return;
        }
        FileReader fr=null;
        BufferedReader br=null;
        try {
            fr=new FileReader(f);
            br=new BufferedReader(fr);
            String str="";
            while((str=br.readLine())!=null)
            {
                System.out.println(str);
            }
            br.close();
            fr.close();
        } catch (Exception ex) {
            System.out.println("ex: "+ex.getMessage());
        }
    }
    public static void writeFile()
    {
        File f=new File("abc.txt");
        System.out.println(
                "path:"+f.getAbsolutePath());
        FileWriter fw=null;
        BufferedWriter bw=null;
        try {
            fw=new FileWriter(f);
            bw=new BufferedWriter(fw);
            bw.write("Welcome");
            bw.newLine();
            bw.write("Hello World");
            bw.flush();
            bw.close();
            fw.close();
        } catch (Exception ex) {
            System.out.println("ex :"+ex.getMessage());
        }
    }
}