public static Object toArrayGuessType(Collection<?> value) {
Class<?> componentType = Reflection.getComponentType(value);
Object array = Array.newInstance(componentType, value.size());
@SuppressWarnings("unchecked")
Iterator<Object> iterator = (Iterator<Object>) value.iterator();
int index = 0;
while (iterator.hasNext()) {
BeanUtils.idx(array, index, iterator.next());
index++;
}
return array;
}
public static <TO, FROM> List<TO> mapFilterNulls(
Function<FROM, TO> converter, Collection<FROM> fromCollection) {
ArrayList<TO> toList = new ArrayList<>(fromCollection.size());
for (FROM from : fromCollection) {
TO converted = converter.apply(from);
if (converted != null) {
toList.add(converted);
}
}
return toList;
}
public static <T> T[] toArray(Class<T> componentType, Collection<T> collection) {
T[] array = (T[]) Array.newInstance(componentType, collection.size());
if (componentType.isAssignableFrom(getComponentType(collection))) {
return collection.toArray(array);
} else {
int index = 0;
for (Object o : collection) {
array[index] = Conversions.coerce(componentType, o);
index++;
}
return array;
}
}