Computer scienceProgramming languagesJavaCode organizationFunctional programmingFunctional streams

Grouping collectors

Theory

Palindrome or not

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Write a collector that partitions all words in a stream into two groups: palindromes (true) and usual words (false). The collector should return Map<Boolean, List<String>>. All input words will be in the same case (lower).

Let's remind, a palindrome is a word or phrase which reads the same backward or forward, such as noon or level. In our case, a palindrome is always a word. For details, see https://en.wikipedia.org/wiki/Palindrome

Hint: the method reverse() of StringBuilder may help you.

Important. You should write only the collector in any valid formats but without ; on the end.
It will be passed as an argument to the collect() method of a stream as shown below.

String[] words = ...
Map<Boolean, List<String>> palindromeOrNoMap = 
        Arrays.stream(words)
              .collect(...your_collector_will_be_passed_here...);

Examples of the valid solution formats: Collectors.reducing(...) or reducing(...)

Sample Input 1: 

aaaa aaa a aa

Sample Output 1: 

{false=[], true=[aaaa, aaa, a, aa]}

Sample Input 2: 

level bbaa ac

Sample Output 2: 

{false=[bbaa, ac], true=[level]}
Write a program in Java 17
import java.util.*;


class CollectorPalindrome {

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

String[] words = scanner.nextLine().split(" ");

Map<Boolean, List<String>> palindromeOrNo = Arrays.stream(words)
.collect(
// write your collector here
);

palindromeOrNo = new LinkedHashMap<>(palindromeOrNo);

System.out.println(palindromeOrNo);
}
}
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