新手求助：想在下面那个方法调用上面那个方法的a怎么做，把filename变成上面那个方法获取的值

System.out.println("请输入您的文件路径：");
Scanner sc = new Scanner(System.in);
String a = sc.nextLine();

        synchronized (fileName) {
            while("".equals(fileName)){
                System.out.println("请输入您的文件路径：");
                Scanner sc = new Scanner(System.in);
                fileName = sc.nextLine();
                sc.close();
            }
        }
    InputStream myxls=new FileInputStream(fileName);
    @SuppressWarnings("resource")
    XSSFWorkbook wb =new XSSFWorkbook(myxls);
    XSSFSheet sheet=wb.getSheetAt(0);//第一个工作表
    return sheet.getLastRowNum()+1; 
}

public XXX(类型) xxx(方法名)(String fileName){
.....
synchronized (fileName) {
while("".equals(fileName)){
System.out.println("请输入您的文件路径：");
Scanner sc = new Scanner(System.in);
fileName = sc.nextLine();
sc.close();
}
}
InputStream myxls=new FileInputStream(fileName);
@SuppressWarnings("resource")
XSSFWorkbook wb =new XSSFWorkbook(myxls);
XSSFSheet sheet=wb.getSheetAt(0);//第一个工作表
return sheet.getLastRowNum()+1;
...
}
调用xxx方法时将参数替换成a

方法名(文件名)
如果不是本类的或者是静态方法调用，需要先new所在的类