如何使用两个密钥（密钥对，值）写入/放入HashMap？

Question

I am using the first solution in this stackoverflow link to create and read a hashMap with 2 keys and one value .ie

Map<Integer, Map<Integer, V>> map = //...

map.get(2).get(5);

How do I put the key/value pairs on this HashMap?

In short, I am looking to do the equivalent of

myMap.put(key, value); 

but for a multi key hashmap.

Answer 1

如果您使用的是Java 8+，则可以执行以下操作（如果您的V类型参数是字符串）：

map.computeIfAbsent(2, e -> new HashMap<>()).put(5, "value");

Answer 2

map.put(2, new HashMap<Integer, V>);

map.get(2).put(5, "value");