java HashMap and HashMultimap 区别

标签：href   guava   diff   hash   put   flow   add   and   check   

http://stackoverflow.com/questions/19222029/what-is-difference-between-hashmap-and-hashmultimap

The difference is that with the second, Core Java implementation,

you need to check whether the Set is there before you insert. Guava‘s Multimap takes care of that for you.

With Core Java:

Set<String> innerSet = opt.get(key);
if (innerSet == null) {
innerSet = new HashSet<String>();
opt.put(key, innerSet);
}
innerSet.add(value);
With Guava:

opt.put(key, value);

java HashMap and HashMultimap 区别

标签：href   guava   diff   hash   put   flow   add   and   check   

原文地址：http://www.cnblogs.com/qbmiller/p/6789659.html