software quality - How would you evaluate the following java solution or how would you solve it? -

how evaluate solution following task in regard of structure, correctness, simplicity, testability(task time approx. 1 hr):

create command-line java program counts unique words text file , lists top 10 occurrences.

english locale , treating hyphen , apostrophe part of word, output should following:

and (514)

the (513)

i (446)

to (324)

a (310)

of (295)

my (288)

you (211)

that (188)

this (185)

solution: wordcalculator.java(main class)

public class wordcalculator {      /**      * counts unique words text file , lists top 10 occurrences.      *      * @param args command line arguments. first argument file path.      * if omitted, user prompted specify path.      *      * @throws java.io.filenotfoundexception if file other reason      * cannot opened reading.      *      * @throws java.io.ioexception if i/o error occurs      */     public static void main(string[] args) throws filenotfoundexception, ioexception {          file file;         list<string> listofwords = new arraylist<>();          // if command argument specified, use file path.         // otherwise prompt user path.         if (args.length > 0) {              file = new file(args[0]);          } else {              scanner scanner = new scanner(system.in);             system.out.print("enter path file: ");             file = new file(scanner.nextline());          }          // reads file , splits input list of words         try (bufferedreader br = new bufferedreader(new filereader(file))) {              string line;             while ((line = br.readline()) != null) {             listofwords.addall(wordutil.getwordsfromstring(line));             }          } catch (filenotfoundexception ex) {              logger.getlogger(wordcalculator.class.getname()).log(level.severe,                 string.format("access denied reading file '%s'.", file.getabsolutepath()), ex);             throw ex;          } catch (ioexception ex) {              logger.getlogger(wordcalculator.class.getname()).log(level.severe,                 "i/o error while reading input file.", ex);             throw ex;          }          // retieves top ten frequent words , frequencies.         map<object, long> freqmap = frequencyutil.getitemfrequencies(listofwords);         list<map.entry<?, long>> toptenwords = frequencyutil.limitfrequency(freqmap, 10);          // prints top ten words , frequencies.         toptenwords.foreach((word) -> {         system.out.printf("%s (%d)\r\n", word.getkey(), word.getvalue());         });     } 

}

frequencyutil.java

public class frequencyutil {      /**      * transforms list map elements , frequencies.      *      * @param list, list parse      * @return item-frequency map.      */     public static map<object, long> getitemfrequencies(list<?> list) {          return list.stream()                 .collect(collectors.groupingby(obj -> obj,collectors.counting()));      }      /**      * sorts frequency map in descending order , limits list.      *      * @param objfreq map elements , frequencies.      * @param limit limit of returning list      * @return list top frequent words      */     public static list<map.entry<?, long>> limitfrequency(map<?, long> objfreq, int limit) {          return objfreq.entryset().stream()             .sorted(map.entry.comparingbyvalue(comparator.reverseorder()))             .limit(limit)             .collect(collectors.tolist());      }  } 

wordutil.java

public class wordutil {      public static final pattern english_word_pattern = pattern.compile("[a-za-z'\\-]+");      /**      *      * @param s string parse list of words. words not matching      * english pattern(a-z a-z ' -) omitted.      *      * @return list of words      *      */     public static list<string> getwordsfromstring(string s) {          arraylist<string> list = new arraylist<>();         matcher matcher = english_word_pattern.matcher(s);          while (matcher.find()) {              list.add(matcher.group().tolowercase());          }          return list;      }  } 

your solution correct if looking less functional programming solution , more oop. should avoid use utils classes static methods. instead of can use wordcalculator adding instance methods , properties map count words. regex patterns heavy performance op , doing loops (in functional way) add splitted words map. other option read file byte per byte , when found non alphabetical character (it text file simple enough check whitespace) dump word stringbuilder map , add 1 counter. avoid possible problems if file huge 1 line text.

update 1 - read words example added:

private void readwords(file file) {      try (bufferedreader bufferedreader = new bufferedreader(new filereader(file))) {         stringbuilder build = new stringbuilder();          int value;         while ((value = bufferedreader.read()) != -1) {             if(character.isletterordigit(value)){                 build.append((char)character.tolowercase(value));             } else {                 if(build.length()>0) {                     addtowordmap(build.tostring());                     build = new stringbuilder();                 }             }         }         if(build.length()>0) {             addtowordmap(build.tostring());         }      } catch(filenotfoundexception e) {         //todo manage exception         e.printstacktrace();     } catch (ioexception e) {         //todo manage exception         e.printstacktrace();     } }