java 8 更優雅的判斷是否為空

public static int getLength(String text) {
        // Java 8
        return Optional.ofNullable(text).map(String::length).orElse(-1);
        // Pre-Java 8
        // return if (text != null) ? text.length() : -1;
    }
    public static void print(String text) {
        // Java 8
        Optional.ofNullable(text).ifPresent(System.out::println);
        // Pre-Java 8
        if (text != null) {
            System.out.println(text);
        }
    }

    public static void main(String[] args) {
        String strA = " abcd ", strB = null;
        print(strA);
        print("");
        print(strB);
        getLength(strA);
        getLength("");
        getLength(strB);
    }