Sorting string value in a case-insensitive manner in Java 8

Question

How do I sort string values in case-insensitive order in the following?

List<Employee> listofEmployees = Arrays.asList(     new Employee(1, "aaa", Arrays.asList(123, 345, 678)),     new Employee(1, "bbb", Arrays.asList(91011, 121314, 1516117)),     new Employee(2, "ccc", Arrays.asList(181920, 212223, 242526)),     new Employee(3, "ddd", Arrays.asList(272829, 303132, 333435)),     new Employee(4, "BBB", Arrays.asList(29, 332, 33)) ); 

I wrote like this:

listofEmployees.stream().sorted(Comparator.comparing(Employee::getName).reversed())         .forEach(s -> System.out.println(s.getName())); 

How do I pass a string case insensitive option here?

Answer 1

Try this

Comparator.comparing(Employee::getName, String.CASE_INSENSITIVE_ORDER) 

Answer 2

As @Tree suggested in comments, one can use the java.text.Collator for a case-insensitive and locale-sensitive String comparison. The following shows how both case and accents could be ignored for US English:

Collator collator = Collator.getInstance(Locale.US); collator.setStrength(Collator.PRIMARY); listOfEmployees.sort(Comparator.comparing(Employee::getName, collator.reversed())); 

When collator strength is set to PRIMARY, then only PRIMARY differences are considered significant during comparison. Therefore, the following Strings are considered equivalent:

if (collator.compare("abc", "ABC") == 0) {     System.out.println("Strings are equivalent"); }