[Java] 파일이 열려있는지 닫혀있는지 확인하는 방법(파일 사용중인지 아닌지 판별)

  //  TO CHECK WHETHER A FILE IS OPENED 
    //  OR NOT (not for .txt files)

    //  the file we want to check
    String fileName = "C:\\Text.xlsx";
    File file = new File(fileName);

    // try to rename the file with the same name
    File sameFileName = new File(fileName);

    if(file.renameTo(sameFileName)){
        // if the file is renamed
        System.out.println("file is closed");    
    }else{
        // if the file didnt accept the renaming operation
        System.out.println("file is opened");
    }

참고사이트

https://stackoverflow.com/questions/1390592/check-if-file-is-already-open