private void addAndOperator() {
		char ch[] = exprBool.toCharArray();
		String newExpreBool = "";

		for (int i = 0; i < ch.length - 1; i++) {

			if ((ch[i] <= 'Z' && ch[i] >= 'A' && ch[i + 1] <= 'Z' && ch[i + 1] >= 'A')
					|| (ch[i] <= 'Z' && ch[i] >= 'A' && ch[i + 1] == '(')
					|| (ch[i] == ')' && ch[i + 1] <= 'Z' && ch[i + 1] >= 'A')
					|| (ch[i] == ')' && ch[i + 1] == '(')
					|| (ch[i] >= 'A' && ch[i] <= 'Z' && ch[i+1] == '!'))
				newExpreBool = newExpreBool + ch[i] + '*';

			else
				newExpreBool = newExpreBool + ch[i];

		}
		newExpreBool = newExpreBool + ch[ch.length - 1];
		this.exprBool = newExpreBool;
	}