Is it possible to convert ArrayList<Integer> into ArrayList<Long>?
arraylist, java
Solution
Not in a 1 liner.
List<Integer> ints = Arrays.asList(1,2,3,4,5,6,7,8,9);
int nInts = ints.size();
List<Long> longs = new ArrayList<Long>(nInts);
for (int i=0;i<nInts;++i) {
longs.add(ints.get(i).longValue());
}
// Or you can use Lambda expression in Java 8
List<Integer> ints = Arrays.asList(1,2,3,4,5,6,7,8,9);
List<Long> longs = ints.stream()
.mapToLong(Integer::longValue)
.boxed().collect(Collectors.toList());
Problem
In my application I want to convert an `ArrayList` of `Integer` objects into an `ArrayList` of `Long` objects. Is it possible?