java - Sorting problem using TreeMap -

i'm trying put key values in hashmap , trying sort out using treemap below. problem if there similar values in map, after sorting considering 1 of them.

   import java.util.*;  public class hashmapexample {              public static void main(string[] args) {              hashmap<string,integer> map = new hashmap<string,integer>();             valuecomparator bvc =  new valuecomparator(map);             treemap<string,integer> sorted_map = new treemap(bvc);              map.put("a",99);             map.put("b",67);             map.put("c",123);             map.put("g",67);             map.put("f",67);             map.put("h",67);             map.put("d",6);              system.out.println("unsorted map");             (string key : map.keyset()) {                 system.out.println("key/value: " + key + "/"+map.get(key));             }              sorted_map.putall(map);              system.out.println("results after sorting");             (string key : sorted_map.keyset()) {                 system.out.println("key/value: " + key + "/"+sorted_map.get(key));             }         }      }      class valuecomparator implements comparator {        map base;       public valuecomparator(map base) {           this.base = base;       }        public int compare(object a,object b) {          if((integer)base.get(a) > (integer)base.get(b)) {           return 1;         } else if((integer)base.get(a) == (integer)base.get(b)) {           return 0;         } else {           return -1;         }       }     } 

after output below

unsorted map key/value: d/6 key/value: a/99 key/value: f/67 key/value: h/67 key/value: c/123 key/value: b/67 key/value: g/67 results after sorting key/value: d/6 key/value: f/67 key/value: a/99 key/value: c/123 

for b,g,f , h keys gave value 67. after sorting map, displaying f value , eleminating b,g , h values. want display outputsomething below

    key/value: d/6     key/value: b/67     key/value: g/67     key/value: f/67     key/value: h/67     key/value: a/99     key/value: c/123 

the reason keys b,g , h being eliminated because comparator provided compares based on values. since have same values, equal keys, means 1 overwrite others.

to print out want, comparator need first compare values, , if equal, compare keys.

int compare(comparable key1, comparable key2) {    // i'm guessing doing like:    // return map.get(key1).compareto(map.get(key2));      // can change     int result = key1.compareto(key2);     if ( result == 0 ) {       result= key1.compareto(key2)      }      return result;  }