输入一行字符串统计各字符出现的次数

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String str = sc.next();
int [] arr = new int[127];
char [] data = str.toCharArray();
for(int i = 0; i < data.length; i++){
char ch = data[i];
int value = (int)ch;
arr[value]++;
}
for(int i = 0; i < arr.length; i++){
if(arr[i] != 0){
char ch = (char)i;
System.out.println(ch+"-->"+arr[i]);
}
}
}