java8 optional防止空指针

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/jm19920911/article/details/82219926

测试用例类:

public class Person {
    private String name;
    private int age;
}

测试代码

public class Test {
    public static void main(String[] args) {
    Person person = null;
    // 如果person为空，则new Person("123", 1)
    Person person1 = Optional.ofNullable(person).orElse(new Person("123", 1));
    System.out.println(person1);
    // 如果person.getName()为空则返回other
    String orElse3 = Optional.ofNullable(person).map((value) -> value.getName()).orElse("other");
    System.out.println(orElse3);
    }
}