Replace multiple occurrences of a character

I try to replace multiple occurrences of a character with a single character.

Input:


hhiii!!! hooowww aaareee yyyooou???

Output:


hi! how are you?

public class CharSingleOccurrence {
    public static void main(String... args){
        charSingleOccurrence("hhiii!!!  hooowww   aaareee   yyyooou???");
    }
    public static void charSingleOccurrence(String str){
        int i=0;
        int j=0;
        char arr[]=new char[50];
        while (i<str.length()-1) {            
            if(str.charAt(i)!=str.charAt(i+1)){
                arr[j]=str.charAt(i);
                i++;
                j++;
            }else{
                i++;
            }
        }
        arr[j]=str.charAt(str.length()-1);
        for(char c:arr){
            System.out.print(c);
        }
    }
}

Here I need review for

• char arr[]=new char[50];

• arr[j]=str.charAt(str.length()-1);

Maybe I am wrong but I prefers to use the regex for this kind of text manipulation.
Here is my code,

System.out.println("hhiii!!!  hooowww   aaareee   yyyooou???"
                      .replaceAll("(.)\\1+","$1"));

StackExchange Code Review Q#5618, answer score: 11