java - Map inside map iteration -


i have following nested map defined in class:

private map<string, map<string, string>> messagesbyfacttypeandcategory;  public void setmessagesbyfacttypeandcategory(map<string, map<string, string>> messagesbyfacttypeandcategory) {     this.messagesbyfacttypeandcategory = messagesbyfacttypeandcategory; }  public map<string, map<string, string>> getmessagesbyfacttypeandcategory() {     if (messagesbyfacttypeandcategory == null) {         return maps.newhashmap();     }     return messagesbyfacttypeandcategory; }

i'm trying unable traverse messagesbyfacttypeandcategory map , data inside display in console.

below code tried far:

map<string, map<string, string>> newmap = executionresult.getmessagesbyfacttypeandcategory(); set set = newmap.entryset();     iterator iterator = set.iterator();     while(iterator.hasnext()) {         map.entry mentry = (map.entry)iterator.next();         system.out.print("key is: "+ mentry.getkey() + " & value is: ");         system.out.println(mentry.getvalue());     }

any appreciated!

if need traverse entries of both maps, can follows:

for (entry<string, map<string, string>> outermapentry : messagesbyfacttypeandcategory.entryset()) {         // outermapentry         system.out.println(outermapentry.getkey() + " => " + outermapentry.getvalue());         (entry<string, string> innermapentry : outermapentry.getvalue().entryset()) {             // inner map entry             system.out.println(innermapentry.getkey() + " => " + innermapentry.getvalue());         }     }

edit. explanation. each outer map entry pair of string key , map<string, string> value. can both key , value on each iteration. instance, can print key , value are. or can traverse value (it map) , print each value entry separately in inner loop.

i believe it's quite clear how iterate "simple" map map<string, string>(see how efficiently iterate on each entry in map?), there no difficulty traversing inner map.


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