[Java](EN) Difference between get(0) and findFirst() in Java List

Environment and Prerequisite

• Java

Difference

get(0) in List

• Return the first element
• Throw IndexOutOfBoundsException when first element is empty

List<String> myList = Arrays.asList("1", "2", "3");
String firstElement = myList.get(0);

findFirst() in Stream

• Return the first element that meets the given condition and if there is no element satisfying that condition then return Optional.empty()
• Available after Java 8

List<String> myList = Arrays.asList("1", "2", "3");

Optional<String> firstElementOptional = myList.stream().findFirst();
if (firstElementOptional.isPresent()) {
    String firstElement = firstElementOptional.get();
}

Keep in Mind

• In data structures like List, let’s make code to handle exceptions such as IndexOutOfBoundsException or NullPointerException when accessing the first or other elements.

Reference

• ChatGPT