how to delete all duplicate characters from string in java code example

Example 1: java program to remove duplicate words in a string

String fullString = "lol lol";
String[] words = fullString.split("\\W+");
StringBuilder stringBuilder = new StringBuilder();
Set<String> wordsHashSet = new HashSet<>();

for (String word : words) {
    if (wordsHashSet.contains(word.toLowerCase())) continue;
    wordsHashSet.add(word.toLowerCase());
    stringBuilder.append(word).append(" ");
}
String nonDuplicateString = stringBuilder.toString().trim();

Example 2: how to remove duplicate elements from char array in java

public static void main(String[] args) {
    Main main = new Main();
    char[] array = {'e','a','b','a','c','d','b','d','c','e'};
    main.getCharArray(array);
}

private char[] getCharArray(char[] array) {
    String _array = "";
    for(int i = 0; i < array.length; i++) {
        if(_array.indexOf(array[i]) == -1) // check if a char already exist, if not exist then return -1
            _array = _array+array[i];      // add new char
    }
    return _array.toCharArray();
}