I'm trying to initialize two variables with an enhanced switch statement: int num = //something boolean val1; String val2; val1, val2 = switch(num) { case 0 -> (true, "zero!"); case 1 ->...

we are using Jess, which is a rules engine, written in Java. It has become pretty old and most of it is written using Java 1.5 and lower language features. Now, we are using this for many years and...

I'm starting a new Spring 5 project with Java 14. It compiled, but gave me a warning: OpenJDK 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely...

Java 13 is coming, so I started studying its new features, one of which is text blocks. I wrote a simple program public final class Example { public static void main(String[] args) { final Stri...

Accidentally I have stumbled into a change in Java 15 that I was not aware of. Suppose I have a very simple question: what is the size of an array of 3 integers? For this, I use JOL. The code is fa...

I'm wanting to create a schedule that wraps around week by week. Because the schedule is the same from one week to the next, the only information I need to store is the day of the week, and the ti...

This question is strongly related to Change private static final field using Java reflection. There, it was asked, how to change a private static final variable. However, the answers on that que...

UPDATE Throughout comments it turned out that the approach for benchmark I taken was incorrect, therefore results were misleading. After correcting my approach (as in accepted answer) results are ...

Reading the JAVA 13 SE specification, I found in chapter 5, section 5.1.7. Boxing Conversion the following guarantee: If the value p being boxed is the result of evaluating a constant expressio...

I'm using Java 13 (13.0.1.hs-adpt) and I enabled the preview language features (mainly because of text blocks). My code is properly annotated with @SuppressWarnings("preview") wherever relevant, b...

I am currently using SonarQube Community Edition version 7.7 on Java 8 JDK using Maven, Iwant to start evaluating OpenJDK 13 . Sonarqube doesn't support OpenJDK 13

Java 13 introduced the yield keyword for the switch expressions. How can I use it and what's the difference between a default return or break value?

I'm trying to create Java module project with Java-13 and Maven. My pom.xml is: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http:...

Since Java 11, a PREVIEW-MODE on the Java Compiler and Runtime can be enabled. It allows to preview new features. (JEP 12) java --enable-preview How can I detect from within Java whether the JVM...

I am creating a spring-boot application, which is running and performing well with openJdk12. The application: https://github.com/jactor-rises/jactor-persistence I am looking for how to set it up ...

All the documentation I've been able to find mentions the 'jre/lib/ext' folder but such does not exist on my JRE 13 installation. I guess somewhere between Java 8 (where I can see the jars in jre...

Files.isHidden(Path.of("c:\\")) returns true on Windows 10, JDK 13 but returns false on JDK 12 same machine. Anyone know why this is?

I'm using a switch expression¹ in Java 12 to convert a string to a HTTP method: static Optional<RequestMethod> parseRequestMethod(String methodStr) { return Optional.ofNullable( switch (me...