Question

用java编写程序实现向文本文件2.txt复制1.txt内容，并读取显示2.txt文件的内容（运用文件java I/O系统编程

Answer 1

不懂追问！

Answer 2

import java.io.*;
public class CopyFile {
public static void main(String[] args) throws IOException {

FileReader in=new FileReader("2.txt");
FileWriter out=new FileWriter("1.txt");
int c;
while((c=in.read())!=-1){
out.write(c);
System.out.print((char)c);
}
in.close();
out.close();
}
}

Answer 3

很简单嘛