Cannot remove hashset in java -

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• concurrentmodificationexception , hashmap 4 answers

i got problem hashset, cannot remove hashset, , here code

//take stopword list file     public void stopwordlist(){     openfile("d:/thesiswork/perlengkapan/stopword.txt");     while(x.hasnext()){          string = x.nextline();             = a.tolowercase();             stopwords.add(a);     }  }     //the method remove stopword public void stopwordremoval(){     stopwordlist();             //if word in streams set equal stopword, should removed     for(string word:streams){         for(string sw:stopwords){              if(word.equals(sw)){                 streams.remove(word);                                    }         }     } 

but, gives me exception, says :

exception in thread "main" java.util.concurentmodificationexception, me? :)

you performing concurrent modification - iterating on collection , modifiying not iterator, should transform code this:

for (iterator<string> = streams.iterator(); it.hasnext();) {     string word = it.next();     (string sw : stopwords) {         if (word.equals(sw)) {             it.remove();             break;         }     } }