利用FileOutputStream类和FileInputStream类拷贝一个文件

import java.io.*;

public class TestFileOutputStream{
    
    public static void main(String[] args){
        try{
            FileOutputStream out = new FileOutputStream("D:/Java/TestFileOutputStream/copy.txt");
            FileInputStream in = new FileInputStream("D:/Java/TestFileOutputStream/TestFileOutputStream.java");
            int b = 0;
            
            while((b = in.read()) != -1){
                out.write(b);
            }
            
            out.flush();
            out.close();
            in.close();
        } catch(FileNotFoundException e){
            e.printStackTrace();
        } catch(IOException e){
            e.printStackTrace();
        } 
    }
    
}