apache common-lang

public static int countMatches(String str, String sub) {



if (isEmpty(str) || isEmpty(sub)) {




return 0;




}





int count = 0;







int idx = 0;







while ((idx = str.indexOf(sub, idx)) != -1) {











count++;











idx += sub.length();







}







return count;



}
public static boolean isEmpty(String str) {







return str == null || str.length() == 0;



}


public class Test {

public static boolean isEmpty(String str){

return str == null || str.length()==0;
}

public static int countMatchesStr(String str, String substr){

if(isEmpty(str)&&isEmpty(substr)){
return -1;
}

int count = 0;
int index = 0;

while ((index = str.indexOf(substr, index)) != -1) {

count++;

index += substr.length();

}
// index = str.indexOf(substr, index);
// while(index != -1){
//
// count++;
//
// index += substr.length();
//
// index = str.indexOf(substr, index);
// }


return count;
}

public static void s(Object o){
System.out.println(" input======= :" + o);
}

public static void main(String[] args) {
Test.s(Test.countMatchesStr("niuniusfsniskdfkjdskjfsdfniuniuniu", "niu"));
}
}