Java HashMapºÍTreeMapµÄÅÅÐòÎÊÌâ×ܽá
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Èç:
TreeMap hm = new TreeMap<String, String>(new Comparator() {
public int compare(Object o1, Object o2) {
//Èç¹ûÓпÕÖµ£¬Ö±½Ó·µ»Ø0
if (o1 == null || o2 == null)
return 0;
return String.valueOf(o1).compareTo(String.valueOf(o2));
}
});
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TreeMap hm = new TreeMap<String, String>(new Comparator() {
public int compare(Object o1, Object o2) {
//Èç¹ûÓпÕÖµ£¬Ö±½Ó·µ»Ø0
if (o1 == null || o2 == null)
return 0;
CollationKey ck1 = collator.getCollationKey(String.valueOf(o1));
CollationKey ck2 = collator.getCollationKey(String.valueOf(o2));
return ck1.compareTo(ck2);
}
});
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Èç¹ûÏë°´ÕÕvalueÅÅÐò»òÕßÊǶÔHashMapÖеÄkey»òvalueÅÅÐòÔò¿ÉÒÔÈçÏ£º
List<Map.Entry<String,Integer>> list = new ArrayList<Map.Entry<String,Integer>>(m.entrySet());
Collections.sort(list,new Comparator<Map.Entry<String,Integer>>(){
public int compare(Map.Entry<String,Integer> o1, Map.Entry<String,Integer> o2){
return o2.getValue()-o1.getValue();
}
});&
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