Whether the instance contains the key
Return the number of times the key was entered into the map
Returns counts associated with the keys in the same order as keys()
Should return the first offset corresponding to the provided key, or -1 if none was found.
Increment the count for a key
Return the keys contained in the map in original insertion order
Put a new key into the map along with an associated integer value.
Number of entries in the Locator map