public final synchronized int numberOfLines(){
            FileInput fin = new FileInput(this.pathName);
            fin.setSupressMessageToTrue();
            boolean test = true;
            int nLines = 0;
            while(test){
                String inputLine = fin.readLineL();
                if(fin.eof){
                    test = false;
                }
                else{
                    if(nLines==Integer.MAX_VALUE){
                        System.out.println("Class FileInput; method numberOfLines; The number of lines is greater than the maximum integer value, " + Integer.MAX_VALUE);
                        System.out.println("-1 returned");
                        nLines = -1;
                    }
                    else{
                        nLines++;
                    }
                }
            }
            fin.close();
            return nLines;
        }