Java Data Type - 如何get第一个字符出现在字符串中的次数

public class Main {
  public static void main(String[] args) {
    int count = 1;
    String userInput = "this is a test";
    char ch = userInput.charAt(0);
    for (int i = 1; i < userInput.length(); i++) {
      if (userInput.charAt(i) == ch)
        count++;
    }
    System.out.println(count);

  }

}