Java function for counting word

Is there any default method in Java that can count total occurrence of a word? For example, how many times stack occurred in a string "stack is stack".

Edit: pleas开发者_如何学JAVAe only Java no third party library.

You can use StringUtils.countMatches(string, "stack") from commons-lang. This doesn't account for word boundaries, so "stackstack" will be counted as two occurences.

There is no built-in .matchCount() method. Here is my impl.

public static int matchCount(String s, String find) {
     String[] split = s.split(" ");
     int count = 0;

     for(int i=0; i<split.length; i++){
        if(split[i].equals(find)){
           count++;
        }
     }
     return count;
 }


String s = "stack is stack";
System.out.println(matchCount(s, "stack")); // 2

You could use:

public static int NumTimesInString(String target, String regex)
{
    return (" " + target + " ").split(regex).length - 1;
}

This will work so long as regex doesn't match a beginning or ending space... Hmm, this might not work for some cases. You might be better writing a function which uses indexOf

public static int NumTimesInString(String target, String substr)
{
    int index = 0;
    int count = -1;
    while (index != -1)
    {
        index = target.indexOf(substr, index);
        count++;
    }
    return count;
}

NOTE: not tested

Either one can be used as:

int count = NumTimesInString("hello world hello foo bar hello", "hello"); 
// count is 3