Write a program that detects the duplicate characters in a string.

package simplilearnJava;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
public class FindDuplicate {
public static void main(String args[]) {
printDuplicateCharacters(“Simplilearn”);
}
public static void printDuplicateCharacters(String word) {
char[] characters = word.toCharArray();
Map charMap = new HashMap();
for (Character ch : characters) {
if (charMap.containsKey(ch)) {
charMap.put(ch, charMap.get(ch) + 1);
} else {
charMap.put(ch, 1);
}
}
Set<Map.Entry> entrySet = charMap.entrySet();
System.out.printf(“List of duplicate characters in String ‘%s’ %n”, word);
for (Map.Entry entry : entrySet) {
if (entry.getValue() > 1) {
System.out.printf(“%s: %d %n”, entry.getKey(), entry.getValue());
}
}
}
}