实现字符串分组[eat, tea, tan, ate, nat, bat] 分组结果 [eat, tea, ate] [tan, nat] [bat]

import java.util.*;

public class first
{
    public static void main(String[] args)
    {
      // [eat, tea, tan, ate, nat, bat] => [eat, tea, ate] [tan, nat] [bat]
        System.out.println("Hello World!");
      List<String> strs = new ArrayList<>();
      strs.add("eat");
      strs.add("tea");
      strs.add("tan");
      strs.add("ate");
      strs.add("nat");
      strs.add("bat");
      HashMap<String,List<String>>  map = new HashMap<>();
      for (String s : strs) {
          char[] cc = s.toCharArray();
        Arrays.sort(cc);
        System.out.println(cc);
        String key = new String(cc);
        if (!map.containsKey(key)){
          map.put(key,new ArrayList<>());
        }
        map.get(key).add(s);
      }
      System.out.println(map.values());
    }
}