Indeed, if a Java Map implementation allows for null values, then it is possible for the Map to return its value for the given key, but that value might be a null.

Transcript - How a Java HashMap internal implementation works One of the most common Java interview questions, and it is an advanced Java interview question, is: How does a Java HashMap work?They're ...

The above class runs through several popular Map implementations (EnumMap, HashMap, LinkedHashMap, TreeMap, Hashtable, WeakHashMap, ConcurrentHashMap) and prints out whether each Map ...