Is this fine for ASCII part?

static ArrayList getASCII_SS(String str){

    if(str.length()==0){
        ArrayList<String> ret=new ArrayList<>();
        ret.add(" ");
        return ret;
    }

    char curr=str.charAt(0);
    String curr_as=String.valueOf((int)curr);
    
    String rest=str.substring(1);

    ArrayList<String> output=new ArrayList<>();

    ArrayList<String>temp=getASCII_SS(rest);
    for(String adder:temp){
        output.add(adder);
        output.add(curr+adder);
        output.add(curr_as+adder);
    }

    return output;
}

@magnus2001 code is fine