HashMap to return default value for non-found keys?
In Java 8, use Map.getOrDefault. It takes the key, and the value to return if no matching key is found.
[Update]
As noted by other answers and commenters, as of Java 8 you can simply call Map#getOrDefault(...).
[Original]
There's no Map implementation that does this exactly but it would be trivial to implement your own by extending HashMap:
public class DefaultHashMap<K,V> extends HashMap<K,V> { protected V defaultValue; public DefaultHashMap(V defaultValue) { this.defaultValue = defaultValue; } @Override public V get(Object k) { return containsKey(k) ? super.get(k) : defaultValue; }}
Use Commons' DefaultedMap if you don't feel like reinventing the wheel, e.g.,
Map<String, String> map = new DefaultedMap<>("[NO ENTRY FOUND]");String surname = map.get("Surname"); // surname == "[NO ENTRY FOUND]"You can also pass in an existing map if you're not in charge of creating the map in the first place.