solution this case:

static boolean isAnagram(String a, String b) { String str1= a.toLowerCase().replaceAll(" ", ""); String str2 = b.toLowerCase().replaceAll(" ", "");

    int[] frequArray = new int[256];
    for (int i = 0; i < a.length(); i++) {
        frequArray[str1.charAt(i)]++;
    }

    for (int i = 0; i < b.length(); i++) {
        frequArray[str2.charAt(i)]--;
    }

    for(int i = 0; i < frequArray.length; i++) {
        if (frequArray[i] != 0) {
            return false;
        }
    }

    return true;
}