iodemo.java~5~

来自「java 使用FileStream 复制文件」· JAVA~5~ 代码 · 共 48 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.print(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;

        try {
            fw=new FileWriter(f);
            fw.write("Welcome\nHello World");
            fw.close();
        } catch (Exception ex) {
            System.out.println("ex :"+ex.getMessage());
        }
    }
}