HashMap to return default value for non-found keys?

dictionary, hashmap, java

Solution

[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;
  }
}

Problem

Original source

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