JAVA常见算法题(三十三)---求子串在字符串中出现的次数

public static void main(String[] args) {
String s1 = "adcdcjncdfbcdcdcd";
String s2 = "cd";
count(s1, s2);
}

public static void count(String str1, String str2) {
int count = 0;
if (str1.equals("") || str2.equals("")) {
System.out.println("你没有输入字符串或子串，无法比较！");
//System.exit(0);
} else {
for (int i = 0; i <= str1.length() - str2.length(); i++) {
if (str2.equals(str1.substring(i, str2.length() + i)))
count++;
}
System.out.println("子串" + str2 + "在字符串" + str1 + "中出现了: " + count
+ " 次。");
}
}