无论如何在Java HashMap中有两个相同的键，但是值不同？

Question

I'm using a HashMap to contain a misspelled word, and a int array that contains its offset in the document, the line number it is on, and the length of that misspelled word. By default, HashMap replaces the old values if the key is already contained. I would like to keep those values, and have duplicate keys.

Is there anyway to accomplish this?

Answer 1

You CANNOT have duplicate keys in Map but you can create a MultiMap ie A map to associate a single key with multiple values. Something like this:

Map<String,ArrayList<String>> myMap = new HashMap<String,ArrayList<String>>();

or you can use readymade multi-map implementations such as:

• Apache MultiMap
• Guava MultiMap

Answer 2

No, a HashMap is always uniquely keyed. If you need aap that a key can have multiple values, look at Guava's MultiMap