src/main/java/com/helger/genericode/Genericode10Helper.java
public static void getAllKeys (@Nonnull final ColumnSet aColumnSet, @Nonnull final Collection <Key> aTarget)
  {
    CollectionHelper.findAll (aColumnSet.getKeyChoice (), o -> o instanceof Key, o -> aTarget.add ((Key) o));
  }
public static void getAllKeys (@Nonnull final ColumnSet aColumnSet, @Nonnull final Collection <Key> aTarget)
  {
    CollectionHelper.findAll (aColumnSet.getKeyChoice (), o -> o instanceof Key, o -> aTarget.add ((Key) o));
  }
Get all contained keys

@param aColumnSet
The column set to scan. May not be <code>null</code>.
@param aTarget
The target collection to be filled. May not be <code>null</code>.