IO字符流---複製文件(自己寫緩衝區)

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class IoFileCopy {
    public static void main(String[] args) {
        FileReader fr = null;
        FileWriter fw = null;

        try {
            fr = new FileReader("F://iodemo.txt");
            fw = new FileWriter("F://iodemo2.txt");

            char[] ch = new char[1024];

            int len = 0;

            while ((len=fr.read(ch))!=-1){
                fw.write(ch, 0, len);
            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if (fw != null){
                try {
                    fw.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (fr != null){
                try {
                    fr.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }
}