Backend>Questions

Java equals() selection

sona11

sona11

Java equals() selection

In Java, if I try to do.equals() on a null string, a null pointer error is issued. I’m wondering whether I can perform the following if I’m attempting to compare if a string is equal to a constant string:
MY CONSTANT STRING.equals(aStringVariable)
I’m sure it’ll work, but is this simply extremely bad code?
This is a common Java idiom known colloquially as a Yoda condition. Personally, I prefer to handle the null situation directly, but the Yoda method is widely used, and any competent Java programmer should quickly grasp what is going on. How should I proceed?

3 comments
/java
4 1150 3

Most Liked

faust

faust

I think that it is important to discuss with your team how the majority feels about this kind of situation and create a guideline for the project.

Anyway, I personally prefer to use Enums instead of this kind of constant.

1
Post #3
finner

finner

Hi @sona11,
If you are using Java8 (or ablove) you can use Optional - for example:

boolean eq = Optional.ofNullable(aStringVariable)
            .map(s -> s.equals(MY_CONSTANT_STRING))
            .orElse(false);

And when the aStringValue is null there will no NullPointerException

I hope I understood the question correctly, does that help?

1
Post #4
sona11

sona11

Thanks you and yes it does help.

1
Post #5

Where Next?

View thread on forum
java
Home Backend>Questions
/java
4 1150 3
Last post

Popular Backend topics Top

The_Exile
Backend>Questions

Not fully understanding the code in the example in "Learn to Program"
/ruby/book-learn-to-program-2nd-edition
19 1501 13
New
Kurisu
Backend>Questions

I'm curious if I can have a feature like Elixir/Phoenix umbrella project when using Ruby On Rails
Following on an old discussion I started on Elixir Forum here, I finally made my mind to learn Ruby on Rails in addition to Elixir/Phoen...
/elixir/ruby/rails/phoenix
20 1995 9
New
dimitarvp
Backend>Questions

Open datasets that are in SQLite format or convertible to it?
Hey everyone, I resumed work on my Elixir <=> SQLite library (which uses a Rust NIF underneath) and I am in a need of small and we...
/elixir#sqlite
11 1344 6
New
joshi
Backend>Questions

Export data from Oracle export files (expdp) to PostgreSQL
Hey everybody! I’m working on the project that includes import of Oracle data to PostgreSQL. That data comes as Oracle export (expdp) fi...
#postgres#oracle
2 1891 1
New
Fl4m3Ph03n1x
Backend>Questions

Dialyzer does not catch errors on returned functions
Background While playing around with dialyzer, typespecs and currying, I was able to create an example of a false positive in dialyzer. ...
/elixir
13 1368 6
New
Fl4m3Ph03n1x
Backend>Questions

How to define Macro for a new Type?
Background So, I am playing around with a concept named “NewType” and I am taking inspiration from languages like F# and Scala. My objec...
/elixir#types
22 1493 9
New
Fl4m3Ph03n1x
Backend>Questions

Elixir Witchcraft IO monad?
Background I have recently been delving into more functional code. My objective right now is to get something similar to the IO Monad (in...
/elixir#monads
3 1158 1
New
KnowledgeIsPower
Backend>Questions

Do your company uses microservices?
Is it monolithic or using micro-services?
#backend
5 776 3
New
AstonJ
Backend>Questions

Psql: error: connection to server on socket "/tmp/.s.PGSQL.5432" failed: No such file or directory
If you’re getting errors like this: psql: error: connection to server on socket “/tmp/.s.PGSQL.5432” failed: No such file or directory ...
#macos/rails/postgresql
1 5553 1
New
Shiny
Backend>Questions

What do you think is a good direction to go for someone with a Rails background?
Hey community, this is my first post here so I will try to be as concise as possible and I appreciate any feedback. I’ve been writing Ro...
/ruby/rails#help-needed
18 727 11
New

Other popular topics Top

DevotionGeo
Backend>Chat

Would you use Erlang now when there is Elixir?
Why, if your answer is yes?
/elixir/erlang
167 4955 52
New
AstonJ
General Dev>Code Editors

Poll: Which code editor do you use?
You might be thinking we should just ask who’s not using VSCode :joy: however there are some new additions in the space that might give V...
#community#polls/vim/emacs#code-editors/vscode#notepad/sublime-text#atom/textmate#codespaces#brackets/onivim#geany
121 5796 61
New
AstonJ
General Dev>Hardware

Seen any cool new keyboards?
We have a thread about the keyboards we have, but what about nice keyboards we come across that we want? If you have seen any that look n...
/keyboards#mechanical-keyboards
49 5910 39
New
DevotionGeo
General Dev>Code Editors

Dendron: a personal knowledge management tool on top of VSCode
/vscode#visual-studio-code
30 7372 9
New
AstonJ
General Dev>Dev Chat

How fast do you type? Check your WPM here!
Do the test and post your score :nerd_face: :keyboard: If possible, please add info such as the keyboard you’re using, the layout (Qw...
typing-speed-test.aoeu.eu
/keyboards
82 7682 31
New
Help
Game Dev>Questions

Can I use Java to program a game for Nintendo switch?
I am trying to crate a game for the Nintendo switch, I wanted to use Java as I am comfortable with that programming language. Can you use...
/java#nintendo
8 4771 3
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: Rebecca Skinner (Author) Interview and AMA!
Author Spotlight Rebecca Skinner @RebeccaSkinner Welcome to our latest author spotlight, where we sit down with Rebecca Skinner, auth...
#author-spotlight/haskell/book-effective-haskell
106 11719 28
New
AstonJ
AI>Chat

How to: Run DeepSeek on Mac, Windows, and Linux!
This is a very quick guide, you just need to: Download LM Studio: https://lmstudio.ai/ Click on search Type DeepSeek, then select the o...
#macs/deepseek#guides#lm-studio
14 9328 10
New
PragmaticBookshelf
Backend>Learning Resources

Simplicity
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
pragprog.com
#pragprog#published-book/book-simplicity
10 6553 8
New
CommunityNews
AI>In The News

From Noise to Image
An interactive, visual guide to the magic behind how AIs generate images from text.
lighthousesoftware.co.uk
0 13 0
New
Back to top

Sponsor Spotlight

EEF

Supporting innovation across the BEAM ecosystem.

Latest in Java

Java Portal ❯

Backend>Questions

Backend Questions ❯

Latest on Devtalk

Devtalk ❯

We ❤️ helpful members!

We reward our most helpful members via our MOTM scheme - by giving away a whopping 25 books per year!

Member of the Month

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

Linux New Media

Publishing Linux Magazine, ADMIN, and MakerSpace for 25+ years.

View all our sponsors ❯

Categories:

Sub Categories:

Popular Portals

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

Linux New Media

Publishing Linux Magazine, ADMIN, and MakerSpace for 25+ years.

View all our sponsors ❯

We're in Beta

About us Mission Statement See our Roadmap