Is it possible to have a HashMap return a default value for all keys that are not found in the set?
[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 extends HashMap {
protected V defaultValue;
public DefaultHashMap(V defaultValue) {
this.defaultValue = defaultValue;
}
@Override
public V get(Object k) {
return containsKey(k) ? super.get(k) : defaultValue;
}
}