自己写的代码去空行器

import java.io.*;

public class RemoveEmp3{
    public static void readwrite(String filePath)throws IOException{
        FileInputStream finput = new FileInputStream(filePath);
        InputStreamReader isr = new InputStreamReader(finput);
        BufferedReader br = new BufferedReader(isr);
        
        File file = new File("new.java");
        if(!file.exists()){
            file.createNewFile();
        }
        FileOutputStream fos = new FileOutputStream(file);
 
    OutputStreamWriter osw = new OutputStreamWriter(fos);
        
        for(String line = br.readLine();line!=null;line = br.readLine()){
            if(line.matches("^[\\s&&[^\\n]]*$")){//空行的转义字符
                ;
            }
            else{
                osw.write(line+"\n");
                System.out.println(line);
            }
        }
        br.close();
        osw.close();
        
    }
    public static void main(String[] args){
        String str1 = "E:/A课程学习资料/软件构造 刘丹/软件构造/代码去空行器（自己写的）/RemoveEmp2.java";
        try{
            readwrite(str1);
        }catch(IOException e){
            ;
        }
    }
}