Clean code

NewCharacterGram.java

public Integer deltaValueWithText(String anotherText) {

    HashMap<Character, Integer> anotherTextCharacterCount = new HashMap<Character, Integer>();
    Integer delta = 0;

    for (Character character : anotherText.toCharArray()) {
        Integer count = anotherTextCharacterCount.get(character);
        count++;
        anotherTextCharacterCount.put(character,count);
    }

    for (Character character : anotherTextCharacterCount.keySet()) {
        Integer currentTextCount = characterCount.get(character);
        Integer anotherTextCount = anotherTextCharacterCount.get(character);

        delta += (anotherTextCount-currentTextCount);
    }

    return delta;
}