Java复制文件

import java.io.*;


public class FileCopy{
public static void main(String[] args){
int a = 0;
FileReader in = null;
FileWriter out = null;
try {
in = new FileReader("d:/FileCopy.txt");
out = new FileWriter("d:/Demo.txt");
while((a=in.read())!=-1){
out.write(a);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}