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This article is about how java uses the Optional class to optimize if-else. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

Optimize if-else using the Optional class

In practice, I've come across code like this that looks fine, but if one of the attribute values is unfortunately null, then, congratulations, you'll like to mention a NullPointerException exception.

String name=school.getGrades (). GetStuendt (). GetName ()

To handle this possible null pointer exception, the traditional way of writing is to write a bunch of if-else statements to handle it, like this--

String name=null;if (null) {Grades grade=school.getGrades (); if (gradewords null) {Student student=grade.getStuendt (); if (student students null) {name= student.getName ();}

As a person who hates if-else very much, how can he tolerate this pile of nested code?

When you encounter this layer upon layer of nested if-else judgment, you can consider using the new jdk1.8 feature Optional class to optimize, and the optimized effect is as follows, which is suddenly much more elegant.

String name = Optional.ofNullable (school) .flatMap (School::getGrades) .flatMap (Grades::getStuendt) .map (Student::getName) .orElse (null); thank you for reading! This is the end of this article on "how java uses Optional classes to optimize if-else". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it out for more people to see!

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