Java convert List of key/value strings to Map

Question

I have a List of strings which are actually keys and values: "key1", "value1", "key2", "value2", ... (every odd item is a key, every even — value). How can I convert it to Map like this "key1" -> "value1", "key2" -> "value2", ... in a beautiful way?

Answer 1

You can simply do:

Iterator<String> it = list.iterator();
while(it.hasNext()) {
    map.put(it.next(), it.next());
}

This will be more efficient than using the get(index) method (in case the list implementation does not allow random access)

Answer 2

Here's a relatively neat way:

var map = IntStream.range(0, list.size() / 2).boxed()
    .collect(Collectors.toMap(i -> list.get(i * 2), i -> list.get(i * 2 + 1)));