How could this Java code be improved:

public static List FindKeys$($Map map, String needle$)\{$

List l $=$ null;

for $($Entry i : map.entrySet$())\{$

if $($i$.$getValue$().$equals$($needle$))\{$

if $($l $==$ null$)\{$

l $=$ new ArrayList$()$;

$\}$

l$.$add$($i$.$getKey$())$;

$\}$

$\}$

return l;

$\}$