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

AstonJ
Backend>Questions

Erlang's not installing on macOS Big Sur "You are natively building Erlang/OTP for a later version of MacOSX than current version"
Just done a fresh install of macOS Big Sur and on installing Erlang I am getting: asdf install erlang 23.1.2 Configure failed. checking ...
#macos/erlang#big-sur#asdf
10 6212 8
New
gagan7995
Backend>Questions

Please tell me how to write a query for this in nodejs
API 4 Path: /user/following/ Method: GET Description: Returns the list of all names of people whom the user follows Response [ { ...
/nodejs
7 3447 3
New
Fl4m3Ph03n1x
Backend>Questions

Is there a way to have Elixir Records without default values?
Background I am trying to find a cheap and easy way to create New Types in Elixir, and Records seem to be just what I would need. Probl...
/elixir
10 1230 2
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
AstonJ
Backend>Questions

Rails db:create error - PG::ConnectionBad: connection to server on socket "/tmp/.s.PGSQL.5432" failed: FATAL: database "_development" does not exist
If when trying to create (or recreate) your dev db with rails db:create you are getting: PG::ConnectionBad: connection to server on soc...
/rails#troubleshooting
3 2357 0
New
Fl4m3Ph03n1x
Backend>Questions

How to get the top X results of a given category using Ecto?
Background I have to queries that return a colossal amount of data on their own. I cannot use Repo.all as doing so would materialize thes...
/elixir#ecto
4 1072 3
New
Fl4m3Ph03n1x
Backend>Questions

Gradient does not recognize type of TypedStruct structures
Background I have a module that uses TypedStruct to create structs. This is the code: defmodule Shared.Data.Authorization do @moduledo...
/elixir#gradient#struct
6 1064 2
New
pillaiindu
Backend>Questions

What's wrong with my Phoenix LiveView code?
Currently reading the book “Programming Phoenix LiveView”. At the end of the Chapter 1, I’m trying to solve the guess game. If the user ...
/elixir/phoenix#liveview
6 1007 4
New
harwind
Backend>Questions

How to Efficiently Find and Remove Duplicates in a Large SQL Database?
I have a large SQL database with millions of records, and I’ve identified duplicate entries. What’s the most efficient way to find and re...
#question
1 666 0
New
pillaiindu
Backend>Questions

What is the difference between using `:references` and `:belongs_to` in a generate command in Rails?
What is the difference between using :references and :belongs_to in the following command? bin/rails generate scaffold LineItem product:...
/ruby/rails
5 824 2
New

Other popular topics Top

siddhant3030
General Dev>Dev Chat

Which vertical monitor do you use?
I’m thinking of buying a monitor that I can rotate to use as a vertical monitor? Also, I want to know if someone is using it for program...
#monitors#programming
51 4892 20
New
AstonJ
General Dev>Hardware

Poll: Which keyboard layout do you use?
poll poll Be sure to check out @Dusty’s article posted here: An Introduction to Alternative Keyboard Layouts It’s one of the best write-...
colemakmods.github.io
#polls/keyboards
10 6048 11
New
PragmaticBookshelf
Backend>Learning Resources

Concurrent Data Processing in Elixir
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
pragprog.com
#pragprog/elixir#published-book/book-concurrent-data-processing-in-elixir
78 6059 24
New
mafinar
Backend>Chat

Data Structures and Algorithms with Elixir
This is going to be a long an frequently posted thread. While talking to a friend of mine who has taken data structure and algorithm cou...
/elixir#algorithms#data-structures
108 11869 31
New
AstonJ
General Dev>Code Editors

Doom-Emacs: Can't find emacs in your PATH
If you get Can't find emacs in your PATH when trying to install Doom Emacs on your Mac you… just… need to install Emacs first! :lol: bre...
#macos/emacs#doom-emacs
4 5837 0
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: Jamis Buck (Author) Interview and AMA!
Author Spotlight Jamis Buck @jamis This month, we have the pleasure of spotlighting author Jamis Buck, who has written Mazes for Prog...
#author-spotlight/ruby/book-the-ray-tracer-challenge/book-mazes-for-programmers
21 6352 9
New
hilfordjames
Windows>Chat

Taskbar Overflow Menu (NOT System Tray Overflow)
There appears to have been an update that has changed the terminology for what has previously been known as the Taskbar Overflow - this h...
#taskbar-overflow-win-11
3 3715 2
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: Bruce Tate (Author) Interview and AMA!
Author Spotlight: Bruce Tate @redrapids Programming languages always emerge out of need, and if that’s not always true, they’re defin...
/elixir/ruby/phoenix/book-seven-more-languages-in-seven-weeks/book-seven-languages-in-seven-weeks#liveview/book-programming-phoenix-liveview
54 5678 23
New
AstonJ
AI>Chat

Post your DeepSeek results
Curious what kind of results others are getting, I think actually prefer the 7B model to the 32B model, not only is it faster but the qua...
/deepseek
15 4275 15
New
mindriot
General Dev>Reviews

Keyboard Review: UHK60V2 vs Defy vs Voyager vs Glove80 vs Svalboard
Ok, well here are some thoughts and opinions on some of the ergonomic keyboards I have, I guess like mini review of each that I use enoug...
/keyboards#uhk60v2#defy#voyager#glove80#svalboard
5 5681 7
New
Back to top

Sponsor Spotlight

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

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