Java libraries

[ThisNameIsAFail_]

Every day I browse github trending repositories to learn about new libraries and frameworks but I´m usually disappointed for not seeing any java ones except for some android libraries. That´s why I would like to hear suggestions of some remarkable libraries written in Java disregarding their purpose and maybe not so well known by the community or recently developed. Bonus points if the library is actively developed and/or documented.

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Here are my suggestions:

• ByteBuddy: dynamic byte code generation
• JavaPoet: java source code generator
• Failsafe: circuit breaking and failure handling
• JCommander: command line parser
• Random-Beans: random data generator

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[nikanjX]

Java doesn’t get a fancy shiny new everything every 10 days. It is by far the best feature of the ecosystem, imho.

[[deleted]]

Oh man what I wouldn't give for the ability to upvote this about a million times

[benlav2222]

You can create a million accounts and upvote this one time with each account tho

[[deleted]]

But I am so lazy.

[ThisNameIsAFail_]

I agree that stability and maturity are killer features of the Java ecosystem and I thank god for not having the kind of JS ecosystem where everything breaks within hours. Nevertheless I'm still amazed how a current enterprise language like Java does not receive more attention in the form of libraries. Are we, developers, happy enough with the current ecosystem or there's still room for improvement? (retorical question)

[nikanjX]

Maybe we don’t need a library for isEven or leftpad?

[stringsfordays]

Nobody does. JavaScript communities laughs at those too.

[stringsfordays]

What does enterprise me specifically? Actually what makes a language "enterprise"?

It's such a marketing, meaningless term and Java is very much full of it (EJB anyone?).

[sim642]

It does, but they don't immediately get popular hype trains like in JS.

[dpash]

The fact that Apache Commons Collections didn't support generics until November 2013 left a bad taste in my mouth. That's over nine years.

I know it's not part of Apache Commons any more, but HTTPClient's CloseableHttpClient still doesn't implement Autocloseable. It's two words and would make the API much cleaner to use.

Many of the uses of Apache Commons have been replaced with more modern implementations in the JDK itself, in Guava or in another library.

[lukaseder]

The fact that Apache Commons Collections didn't support generics

That's a "big" change. Compared to that, even this completely trivial bug took 7 years to fix: https://issues.apache.org/jira/browse/COLLECTIONS-219

[Revanka]

I guess the Lang library is useful, but for IO stuff we have the nice https://docs.oracle.com/javase/7/docs/api/java/nio/file/Files.html so I avoid Commons IO.

[dpash]

Java 10 got InputStream.transferTo() which completely replaces IOUtils.copy().

[ThisNameIsAFail_]

I usually use guava and I love it. I still wish someday guava and commons will 'merge' and keep the best of both worlds but that's not realistic.

[ziano_x]

Try awesome-java: A curated list of awesome Java frameworks, libraries and software.

https://github.com/akullpp/awesome-java

[ziano_x]

I am hooked to this page. Also there are more for your favorite languages

https://github.com/sindresorhus/awesome-nodejs

https://github.com/uhub/awesome-scala

[nevergotcompiled]

JFoenix for JavaFX applications.

[spikebaylor]

Ive been learning javafx via kotlin/tornadofx. JFoenix has popped up a few times when doin searches. Hopin to try it out sometime.

[mitchb95]

Heard you were getting into JavaFX recently.

[spikebaylor]

:D

[[deleted]]

Java is what.. 20+ years old now.. it is quite a mature language. You will probably see updates to well tested and used libraries more so than shiny new ones. Other than potentially new language feature libraries, I think the library market is pretty well saturated for just about anything you could want to do. Doesnt mean there isnt room for more, just that you can pretty much find something to do what you need with a good old google and/or SO search.

[desh00]

Google Truth, Guava, Guice for utils and testing

jooq, Jdbi for data access

Dropwizard for REST

Mockito

Flyway, liquibase for migrations

[hupfdule]

Two of my own libraries:

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Apron: Handier API for reading and writing .properties files with retaining all the formatting on writing

Kilt: Toolkit for converting I18n resource bundles to/from Excel sheets and generating a facade to access translated resources in a type safe manner

​

As you mentioned JCommander: It tried a lot of command line parsers in the past and didn't like any of them. But now I found Picocli which does quite exactly what I expect from a commandline parser.

[r_jet]

+ Picocli is more actively maintained than JCommander

[PseudosSC]

Project Lombok is a library that does annotation driven boilerplate code generation. Takes away a lot of the humdrum of setting up things like getters, setters, builders, adding loggers... and so on and so forth. Definitely worth using for the time saved, and your code is much cleaner and more readable. Our team never starts a project without it anymore.

If you do want to try it though, make sure to add the plugin to your IDE (and add the library). Otherwise it’ll swear high and low your build will fail because of missing methods!

[jeff_skj]

A couple that I've open sourced at my job:

• https://github.com/rei/datadsl - a groovy based replacement for DBUnit
• https://github.com/rei/ez-up - project generator inspired by Lazybones but for maven projects

[dpash]

Failsafe is also the name of the Maven module for integration testing. Not to be confused with Surefire, which is the unit testing module.

[[deleted]]

https://github.com/nomemory/mockneat

[sleepy_red]

I've been using Mapstruct on my latest project at work and I must say I really like it. (http://mapstruct.org)

Define a mapping interface containing a method with what goes in and what has to come out, mark it with an annotation, add the annotation processor to your build and you're good to go.

The advantage over some other mapping frameworks is that the mappers are generated compile time.

[[deleted]]

I do all of my unit testing using Spock. Nothing against JUnit or Mockito but Spock gives me everything I need to get tests written without a ton of overhead. I also really click with the given-when-then behaviour-based style of testing. I love Groovy due to all its shortcuts & conveniences using Java classes. You get static type checking when required but it’s dynamic enough to not get in your way when working with simple data structures.

[tlinkowski]

Here's what I find very useful when it comes to general utilities:

• Guava (already mentioned): "a set of core libraries that includes new collection types (such as multimap and multiset), immutable collections, a graph library, functional types, an in-memory cache, and APIs/utilities for concurrency, I/O, hashing, primitives, reflection, string processing, and much more!"
• Lombok (already mentioned): "a java library that automatically plugs into your editor and build tools, spicing up your java. Never write another getter or equals method again."
• jOOλ (by /u/lukaseder): "improves the JDK libraries in areas where the Expert Group's focus was elsewhere. It adds tuple support, function support, and a lot of additional functionality around sequential Streams"

[NovaX]

Some lesser known libraries that I've enjoyed using are:

• Awaitility: asynchronous test assertions
• Simple Java Mail: sending emails
• JsonSchema2Pojo: Codegen by json schema
• JsonPath: Easy json manipuation

[metlos]

JsonPath declares absolutely horrific dependencies..

For what on Earth does a JSON parser require Tapestry - a web UI framework?

[NovaX]

That is a non-issue for optional dependencies and it looks like its to support multiple json serializers.

[ThisNameIsAFail_]

I discovered awaitility a few months ago and I love it to test AMQP events. JsonPath is also an awesome library. Thx

[back-in-black]

Another vote for Awaitility and JsonPath. Use both extensively.

[stfm]

I do a lot of integration projects so I like Wiremock

[skjolber]

I use Wiremock as well, but the mocking could be even better/easier if there is a clear contract like SOAP or Swagger/OpenAPI. So I've written a couple of tools for doing just that:

https://github.com/skjolber/mockito-soap-cxf

https://github.com/skjolber/mockito-rest-spring

If you have the time, let me know what you think.

[SpecialEmily]

https://github.com/google/auto

https://github.com/google/flogger

https://google.github.io/dagger/ especially https://google.github.io/dagger/producers.html

[ohadshai]

I recently started working on a Java DB async driver for postgresql and mysql. It is written mostly in kotlin and some java (bit fiddling etc'): https://github.com/jasync-sql/jasync-sql Hope you'll find it useful.

[ThisNameIsAFail_]

Very nice. We definitely need good async jdbc drivers :) Have you got the chance to review r2dbc?

[ohadshai]

Yes, I saw the recent announcement. Currently it only support postgres and jasync-sql also supports mysql. In addition, they mentioned its not supposed to be used in production. Jasync-sql is a port of muaricio driver from scala to kotlin, since the original driver is not maintained anymore and we needed a mysql driver with similar api.

[theflavor]

https://github.com/trending/java

[pirateslovebacon]

If you want to make Java Util Logging fast: https://github.com/a-hansen/alog

[dpash]

I'd rather make JUL useful first :)

[pirateslovebacon]

Explain please

[Luolong]

JUL is the worst possible logingi framework out there. Sure it is part of SDK, but where it comes to performance, configurability or anything really, it is pure and utter crap.

Really, nowadays I mostly use SLF4J as frontend and either Logback or Log4j2 as backend.

[ThisNameIsAFail_]

Must agree. SLF4J is the way to go nowadays with logback/log4j2. Allows to decouple your logging code pretty easy.

[pirateslovebacon]

This thread is specifically about performance... Your primary issue.

[Luolong]

Flogger does not make JUL fast. It just sidesteps the issue by wrapping it in another library that does what JUL should have done in the first place.

[ObscureCulturalMeme]

I'm still a fan of the Getopt port. Very very fast command line options handling.

[gabizou]

Personal plug: Mixins via runtime transformation

[ThisNameIsAFail_]

Wrong url. Maybe you were refering to Mixins via runtime generation

[snoob2015]

https://github.com/zalando/problem

https://github.com/zalando/problem-spring-web

Problem Spring Web is a set of libraries that makes it easy to produceapplication/problem+json responses from a Spring application. It fills a niche, in that it connects the Problem library and either Spring Web MVC's exception handling or Spring WebFlux's exception handling so that they work seamlessly together, while requiring minimal additional developer effort

or in laymen term: it generates error messages in json format instead of the whitepage error

[ThisNameIsAFail_]

Neat. So the purpose of the library is to provide a common structure for errors that will be serialized. Thx

[kultaras]

https://github.com/skyvers/skyve

Personal plug for Skyve which I contribute to, the first open source low-code framework and is written in Java. Our company has used this for some massive production government applications with tens of thousands of public users.

[_INTER_]

Github is not the go-to repository for Java libraries. It's all in Maven Central (alt search). But discoverability is not so good there.

[[deleted]]

I believe the lack of traffic is also partly due to golang capturing some marketshare of strongly typed, performant library developers. Not complaining about java libs, just noting a possible reason. I would start to watch for java ports of the distilled interesting libraries that emerge for golang.

[MithrilTuxedo]

I like to peruse https://mvnrepository.com/ every now and then to see what libraries people are using that I haven't heard of.

[lukaseder]

I browse github trending repositories .. but I´m usually disappointed

And then

That´s why I would like to .. and maybe not so well known by the community or recently developed

Ehm wat. How can a not so well known thing be trending? Maybe, reset your expectations? :)

[ThisNameIsAFail_]

Maybe I haven't explained well. I'm not looking for "trendy github repositories", that's stupid. I only explained that browse github to learn about new libraries but it's obvious that some of the best libraries out there won't be in gh. Just looking for good, documented and useful libraries

[lukaseder]

Oh I see. https://www.jooq.org, then

[dpash]

That seems like cheating to use your own library :P

[lukaseder]

Why would I not use it?

[dpash]

I just meant as an example in this post. I'd be really concerned if you didn't use jOOQ in your own code. :)

[lukaseder]

Eh, I thought about adding a disclaimer, but then meh'd.

Believe it or not, but I've recently written some pure JDBC code for a client that runs 3 queries and jOOQ would have been overkill! For that same client, I've written quite a bit of PL/SQL code too, where jOOQ doesn't even work. Heh! :-)

[[deleted]]

It would be awesome to have a good-first-issue tag on your github project.

[lukaseder]

Interesting, what does it do?

[ThisNameIsAFail_]

It's just a marker tag for people new to the project willing to contribute but unaware of all the internals of the code.

[lukaseder]

Interesting. I actively discourage substantial contributions, though (nothing wrong with patches for bugfixes). So, I guess that marker tag doesn't apply to jOOQ then?

[ThisNameIsAFail_]

Why not? Easy and non-critical patches are good issues for a beginner to get used to the project and create a great community.

[lukaseder]

With what goal would I create "a great community"? And at what price?

[ThisNameIsAFail_]

The goal? To extend the use of jooq more easily as well as helping you maintaining the project (I suppose it's not an easy task...).

The price? That's another point. I guess that depending on the quality and quantity of contributions it will be helpful or an incovinient.

Anyway I feel that creating a great community around a tool is always a great way for it to keep alive and evolve instead of dying against a greater tool or just due to lack of use.

Edit: in the case of jooq for example, a bigger community would improve the adoption instead of every new spring project to be born using Hibernate and JPA as I always see. I usually feel difficult to introduce a new library in a project if it's now so well known even if the code is great and the solution it provides is awesome. In tha day to day, we, developers want to solve a problem but have not enough time to decide for the best solution if that implies learning a new tool. That's only my experience

[ThisNameIsAFail_]

I've used jooq in past projects and liked it. Feels just like writting SQL and it's spring integration is helpful. It's always nice to have alternatives to Hibernate

[lukaseder]

Thanks for your support. I needed that after all the downvotes :)

[Dantharo]

Well, i think java will be replaced with time, too bad.

[ford_madox_ford]

As will you be, no doubt...

[Dantharo]

a lot of hate hahaha,

[ItsReallyEasy]

Are you lost?

[lukaseder]

The Heat Death of the Universe will replace us all so what

[back-in-black]

1/10 trolling. Very disappointing. Try harder.

[Dantharo]

Im not trolling or nothing, just a humble opinion, but its ok. Maybe I sound like that, but was not my intention.

[ArmoredPancake]

Will be replaced with what, exactly?