java 之死循環

public class StringTest {
    public static void main(String[]  args) {
        System.out.println(getStringCount("hellojava,nijavahaojava,javazhenbang", "java"));
    }

    public static int getStringCount(String str,  String key){
        int count = 0;
        int index = 0;
        while ( (index = str.indexOf(key) ) != -1) {
            count++;

            System.out.println(str);
            // 更新目標串
            str = str.substring(index + key.length());
            System.out.println(str);
        }
        return  count;
    }
}