记算出一个字符串出现的次数

public class TestString {

	public static void main(String[] args) {
		String s1 = "abcdefghiabcjklmnopqrabcstuvwxyzabc";
		String s2 = "a";
		
		int count = (s1.length() - s1.replace(s2, "").length())/s2.length();
		System.out.println(count);
	}

}