Maven support for Java 9 in general and tests in particular is still under development – many things work but others might not. Without seeing the stack trace for the NPE, it is of course speculation, but I assume you ran into this error. More generally, the question of how exactly unit tests will work … Read more
Welcome to Testing In The Modular World! Which kind of tests do you want write? Extra-module tests: Create a test-only project (no “src/main” directory) and declare a “src/test/java/module-info.java” module descriptor. In-module tests: As it was from Day 1 you need to “blend in”/merge/shadow your test classes into your main classes or vice versa. Here you … Read more
The purpose of JMODs are not well documented and existing documentation is rather sparse. Here is an in-depth explanation of system, from my understanding. Parts of this answer are rather long, verbose, partially redundant, and a tough read. Constructive, structural, or grammatical edits are more than welcome to improve readability for future readers. Short(er) Answer … Read more
Found the answer based on intellij output:) I had to add the location of the classes to the vm arguments in the run configurations as well as the module name/path to main. like below. See the java -help command for more info regarding -m and -p
The include directory is for header files, such as jni.h, that are needed when compiling C/C++ code that uses JNI and other native interfaces. It’s nothing to do with jlink. The jlink tool can create a run-time image for another platform (cross targeting). You need to download two JDKs to do this. One for the … Read more
// to scan the module path ClassLoader.getSystemResources(resourceName) // if you know a class where the resource is Class.forName(className).getResourceAsStream(resourceName) // if you know the module containing the resource ModuleLayer.boot().findModule(moduleName).getResourceAsStream(resourceName) See a working example below. Given: . ├── FrameworkCore │ └── src │ └── FrameworkCore │ ├── com │ │ └── framework │ │ └── Main.java │ … Read more
You can use your library as an automatic module. An automatic module is a module that doesn’t have a module descriptor (i.e. module-info.class). But what name do you need to specify to refer to an automatic module? The name of the automatic module is derived from the JAR name (unless this JAR contains an Automatic-Module-Name … Read more
You can use class path and module path in parallel, but there are a few details to consider. Dependency Module Path ~> Class Path Explicit modules (JARs with a module descriptor on the module path) can not read the unnamed module (JARs on the class path) – that was done on purpose to prevent modular … Read more
The following code achieves module path scanning in Java 9+ (Jigsaw / JPMS). It finds all classes on the callstack, then for each class reference, calls classRef.getModule().getLayer().getConfiguration().modules(), which returns a a List<ResolvedModule>, rather than just a List<Module>. (ResolvedModule gives you access to the module resources, whereas Module does not.) Given a ResolvedModule reference for each … Read more
I first answer your actual question (“What is an automatic module?”), but I also explain what they are there for. It is hard to understand why automatic modules behave the way they do without that information. What is an automatic module? The module system creates a module from every JAR it finds on the module … Read more