java - Custom SortComparator not working in MapReduce wordcount program -

i trying understand how mapreduce sorts map output keys , sort algorithm uses. have text file this

a b e f c b 

how performs sorting these keys. implemented custom sortcomparator class extending writablecomparator interface. wanted see how sorting happening writing operations file.

public static class mysortcomparator2 extends writablecomparator{    @override   public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {        text x=new text("");       text y=new text("");       try {         x.readfields(new datainputstream(new bytearrayinputstream(b1)));         y.readfields(new datainputstream(new bytearrayinputstream(b2)));          filewriter writerofcomparisions=new filewriter("/home/srimanth/comparisons",true);         writerofcomparisions.write("comparing "+x.tostring()+" "+y.tostring());         writerofcomparisions.write(" ----> returning "+x.compareto(y));         writerofcomparisions.write("\n");         writerofcomparisions.close();      } catch (ioexception e) {         e.printstacktrace();     }       return x.compareto(y);   } 

the output of comparisons file this

comparing ----> returning 0 comparing ----> returning 0 comparing ----> returning 0 comparing ----> returning 0 comparing ----> returning 0 comparing b ----> returning 1 comparing c ----> returning 2 comparing f ----> returning 5 comparing e ----> returning 4 comparing b ----> returning 1 comparing b c ----> returning -1 comparing c f ----> returning -3 comparing f e ----> returning 1 comparing e b ----> returning 3 comparing b ----> returning 1 

what sorting algorithm , final output of wordcount

b   1 c   1 f   1 e   1 b   1   1 

looks mapreduce did not happen properly. here mapper , reducer classes.

  public static class tokenizermapper        extends mapper<object, text, text, intwritable>{      private final static intwritable 1 = new intwritable(1);     private text word = new text();      public void map(object key, text value, context context                     ) throws ioexception, interruptedexception {       stringtokenizer itr = new stringtokenizer(value.tostring());        while (itr.hasmoretokens()) {         word.set(itr.nexttoken());         context.write(word, one);        }     }   }    public static class intsumreducer        extends reducer<text,intwritable,text,intwritable> {     private intwritable result = new intwritable();         public void reduce(text key, iterable<intwritable> values,                        context context                        ) throws ioexception, interruptedexception {         int sum = 0;       (intwritable val : values) {         sum += val.get();       }        result.set(sum);       context.write(key, result);     }   } 

what doing wrong. appreciate help. in advance.

did set following driver code?

job.setsortcomparatorclass(mysortcomparator2.class);