Printing out a HashMap using an Another HashMap's key as values

Question

If I have a HashMap such as

{opst=post pots stop spot tops opts,
 art=rat tar art,
 glos=slog,
 gopr=gorp,
 fgor=frog,
 aprt=trap tarp part,
 dgo=dog god,
 act=act cat tac,
 fglo=flog golf}

and a HashMap such as

{opst=otsp, art=atr, fgor=grof, aprt=arpt, dgo=gdo, act=atc}

How would I use the second HashMap as my key to print out something like...

arpt part tarp trap
atc act cat tac
atr art rat tar
gdo dog god
grof frog
otsp opts post pots spot stop tops

Answer 1

Assuming your first HashMap is called firstMap and the second is secondMap , then navigate through the keys of secondMap to print the values stored on first map. Here's a code sample:

for (String secondMapKey : secondMap.keySet()) {
    System.out.println(firstMap.get(secondMapKey));
}

Another option may be iterating through the entries of secondMap of the second map and get the keys (in case you also need the value of secondMap along to the key):

for (Map.Entry<String, String> entry : secondMap.entrySet()) {
    System.out.println(firstMap.get(entry.getKey()) + " " + entry.getValue());
}