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Java Java Data Structures Exploring the Java Collection Framework Maps

cant run the code!

Hello could some help me !

Example.java:45: error: not a statement
Map<String, List><Treet>> treetsByAuthor = new HashMap<String, List<Treet>>();
Example.java:45: error: ';' expected
Map<String, List><Treet>> treetsByAuthor = new HashMap<String, List<Treet>>();
Example.java:45: error: illegal start of expression
Map<String, List><Treet>> treetsByAuthor = new HashMap<String, List<Treet>>();
3 errors

MY code!

import java.util.Arrays; import java.util.Date; import java.util.HashSet; import java.util.HashMap; import java.util.Map; import java.util.Set; import java.util.TreeSet; import java.util.List; import java.util.ArrayList;

import com.teamtreehouse.Treet; import com.teamtreehouse.Treets;

public class Example {

public static void main(String[] args) { Treet[] treets = Treets.load(); System.out.printf("There are %d treets. %n", treets.length);

Set<String> allHashTags = new HashSet<String>();
Set<String> allMentions = new TreeSet<String>();
for (Treet treet : treets){
System.out.printf("Hash tags: %s %n", allHashTags);
System.out.printf("Mentions: %s %n", allMentions);

Map<String, Integer> hashTagCounts = new HashMap<String, Integer>();
for (Treet treet : treets){
   for(String hashTag : treet.getHashTags()){
      Integer count = hashTagCounts.get(hashTag);
        if (count == null){
          count = 0; 
          hashTagCounts.put(hashTag, count);  

} System.out.printf("Hash tag counts: %s %n", hashTagCounts);

  Map<String, List><Treet>> treetsByAuthor = new HashMap<String, List<Treet>>();

  for (Treet treet : treets){
    List<Treet> authoredTreets = treetsByAuthor.get(treet.getAuthor());
    if(authoredTreets == null){
      authoredTreets = new ArrayList<Treet>();
      treetsByAuthor.put(treet.getAuthor(), authoredTreets);

authoredTreets.add(treet); }

System.out.printf("Treets by author: %s %n ", treetsByAuthor); System.out.printf("Treets by nickrp: %s %n ", treetsByAuthor.get("nickrp"));



1 Answer

Florian Tönjes
.a{fill-rule:evenodd;}techdegree seal-36
Florian Tönjes
Full Stack JavaScript Techdegree Graduate 50,856 Points

Hi Araz,

at line 45 you have a typo. In your code it's "Map<String, List><Treet>>". It should be "Map<String, List<Treet>>". See if that helps.

Kind Regards, Florian

Thank you its works NOW!