Libera #java

Help! My Java Locale is Wrong in JDK11!

We discovered this issue when a user from the Netherlands reported that, upon upgrading to Java 11, his application now reported that the week started on Sunday. This is incorrect for the Netherlands, but the real issue was the change of behavior. With JDK11, Java now loads locales differently. https://www.oracle.com/technetwork/java/javase/documentation/java11locales-5069639.html#providers details the loading behavior for JDK11, and how it supersedes previous versions. Notably, CLDR...

Apr 1, 2019 — 1 minute(s) read

Jackson-databind and Default Typing Vulnerabilities

Today, GitHub sent out security notices to owners of projects using old jackson-databind versions (older than 2.8.11.1 and 2.9.5). These notices pertain to this issue. I have talked about its relevance before on IRC, but since it is getting more attention now, I will describe it here again. The Problem The “bug” comes from using the so-called default typing. This feature allows a user to deserialize subclasses (or...

Oct 16, 2018 — 5 minute(s) read

#jackson #json #security #serialization #xml

OpenJDK 11 on Fedora

Interesting in running the current version of Java (and its compiler) on your Fedora instance? It’s easy: sudo dnf install java-11-openjdk-devel sudo alternatives --config java # select Java 11 sudo alternatives --config javac # if necessary, select java 11 Note that this is still labeled as the “early access” version as of this writing – but the early access version is virtually identical to the released version.

Oct 10, 2018 — 1 minute(s) read

#fedora #java-11 #openjdk

The JavaChannel Podcast, Episode XVII (17)

The XVIIth podcast is live! … one wonders why the Roman Empire didn’t last much longer, doesn’t one. One also wonders how long one can refer to oneself in the whatever-person this is. (It’s… second-person? No, folks, it’s “third person.” English grammer fumbling and lesson over.) In this podcast, we chase a few things: the discussion topic centers back around on Python vs. Java, and why one might encounter one...

Aug 29, 2018 — 3 minute(s) read

#case #concurrenty #equals #hibernate #jakarta-ee #java-12 #java-ee #jep #kotlin #pdf #podcast #podcast-17 #spring #spring-boot #switch #systemd #threads #tomee

The JavaChannel Podcast, vol 16

It’s only been six months, so it’s finally time for a new podcast. This one doesn’t even pretend to go over the mountains of killer content from ##java since the last podcast – it focuses on some of the more recent links, and that’s it. Well, apart from talking about the Java ecosystem a bit, especially in contrast with Python, an upstart language that’s making a lot of headway lately thanks...

Aug 16, 2018 — 3 minute(s) read

#docker #functional #jakarta-ee #java-ee #json #maven #netbeans #openjdk #podcast #podcast-16 #toml #yaml

Gradle Properties

Gradle supports properties in builds just like Maven does, but the actual documentation and examples are harder to come by. This article will show you something that actually works. In Maven, you typically have a dependencyManagement section that declares the dependencies with versions; I typically put the versions in a properties block so that they’re all located in a nice, handy, easy-to-manage place. See https://github.com/jottinger/ml/blob/master/pom...

Aug 1, 2018 — 2 minute(s) read

#gradle #maven

Using multiple cores, the basics

The problem with multicore code Having an application use more than one CPU during its execution introduces an explosion of execution paths. Instead of a simple “first Java executes the first line of this method, then, it executes the second line of this method, all the way to the end,” it becomes: “An arbitrarily chosen thread chooses an arbitrary number of instructions to execute, then the VM will make an arbitrary choice as to whether...

Jun 29, 2018 — 9 minute(s) read

#concurrency #memory-model #threads

Article on java.time

Channel denizen (yes, that’s what we call people in the ##java channel, “denizens”) yawkat has published “An introduction to java.time,” an article to try to clear up some of the confusion around the time API in Java: things like LocalTime, OffsetTime, and the like. If you’re still using Date, this article is for you. Includes handy ways to convert between the time types, and is likely to grow further at need.

Apr 23, 2018 — 1 minute(s) read

#310 #java-time #joda-time #time

JavaChannel’s Interesting Links podcast, episode 15

Welcome to the fifteenth ##java podcast. Your hosts are Joseph Ottinger, dreamreal on the IRC channel, and Andrew Lombardi (kinabalu on IRC) from Mystic Coders. As always, this podcast is basically interesting content pulled from various sources, and funneled through the ##java IRC channel on freenode. You can find the show notes at the channel’s website, at javachannel.org; you can find all of the podcasts using the tag (or even “category”) “podcast”, and...

Feb 13, 2018 — 3 minute(s) read

#concurrency #gpu #graal #hibernate #hystrix #jvmti #okhttp #podcast #podcast-15 #repl #resilience4j #retry #retry4j #specifications

Caching All OkHttp Responses

When (integration) testing scrapers you need to strike a balance between “get as much input data as possible to cover parsing edge-cases” and “don’t DoS the backend, please”. Caching can help with that, and gives you a nice performance boost during testing on top. The OkHttp http client library contains a cache built-in but by default it follows HTTP server caching headers. It also allows you to set a particular request to...

Feb 9, 2018 — 1 minute(s) read

#kotlin #okhttp