isDirectory() not working for UNIX directory

I am getting the isDirectory() value as false for the below code :-

public void validateFile() throws IOException {

        File dir = new File(Labels.INPUT_FILE_DIR).getCanonicalFile(); 
        // Labels.INPUT_FILE_DIR is ./Input (i.e. my Input folder in UNIX server
        String code, fileName = "";
        ArrayList<String> fileList = new ArrayList<String>();

        Logger.info(cName,mName,"");
        System.out.println("dir.isDirectory() " + dir.isDirectory()); // getting false here

        if (dir.isDirectory()) {

            for (File tempFile : dir.listFiles()) {
                System.out.println("inside the for loop ");

            }
        }

    }

Am i doing something wrong ? Could anyone please help me out.