I'm having a new problem this morning with my project (it worked fine on Friday). Eclipse seems to be having trouble figuring out it's module / class path, and nothing I'm trying seems to affect it. I'm using the following Eclipse configuration:
Version: 2019-03 M1 (4.11.0 M1)
Build id: 20190117-2133
Oracle JDK 10.0.2
My project is a Java Maven multi-module (those are maven modules, not java modules) project, but does not define any java modules itself (we haven't converted it yet). When attempting to compile it, eclipse throws up its hands and sends the message
"The package java.sql is accessible from more than one module: <unnamed>, java.sql".
While, on the surface, this seems helpful, I cannot find another module that defines the java.sql package, and the only instance of a class from the package (e.g.: java.sql.ResultSet) exists within the JDK system supplied library. This also happens with the javax.xml package with the same error.
I've attempted closing and re-opening eclipse, performing a clean, and a maven update project for everything, to no avail. I've inspected the eclipse .log file, and there's nothing useful in there. Is there anyway to figure out what other module Eclipse thinks it's pulling that package from?
My next step is to delete the entire project and re-import it.
UPDATE: I think I may have found the offender... there's a dependency that declares a couple of classes into the java.sql package, and that's probably borking things up. The specific JAR is net.sourceforge.hatbox:hatbox:1.0.b8, and is a transitive dependency of the com.h2database:h2:1.4.197 jar. Is there any way to tell eclipse to ignore the package from that JAR?
Update 2: Build Path:
I'm not sure I count this as a true solution, but I was able to find a workaround to my problem. I downgraded eclipse from the installed version listed in the question (4.11.0) to the base photon install (4.8.0), and I can now compile and work again.
Related
So I have been facing these issues in so many JavaFX Gradle based projects in Intelli J Idea IDE. This has pushed me to the point where I had to manually download library files and make them part of my projects as a workaround.
The gradle projects I have they keeping failing when ever i run the > Task :compileJava in the IDE, for example in this particular that made me create the issue is that i have successfully imported the socket io lib from maven implementation 'io.socket:socket.io-client:2.0.1' , i have managed to import it and write a bit of sample code for it and i have added
requires engine.io.client;
requires socket.io.client;
in the module info file . So when its time to run this fails stating that
error: module not found: socket.io.client
requires socket.io.client;
error: module not found: engine.io.client
requires engine.io.client;
I have tried on JDK 13,16,17 to see if I am missing something but keeps on failing to run , so I have noticed now as a trend in my previous JavaFX project in which i managed to get away with.
So if there is anyone who understands what's wrong with Gradle set up please help.
This answer outlines an approach rather than a concrete solution.
socket.io.client and engine.io.client are not module names.
The socket.io-client library is not Java platform modularized (as far as I can tell), so it will be an automatic module.
The name of the module will be derived from the jar name. I don't know the exact translation as the jar name has . and - characters which may be remapped (or not) to make the module name valid. Try first the exact jar file name. There can be only one module per jar.
Additionally to requiring the right name, the jar needs to be on the module path. Maven will do this automatically for automatic modules, Gradle will not. I am not a Gradle expert, so will not provide advice on how to do that for Gradle.
If you use the right name in module-info and ensure the jar is on the module path, then it may work, or it may be incompatible with the Java module system in ways that are not easily fixable by you (i.e. the broken module must be fixed by the module maintainers).
You can raise an issue for the library maintainer for them to create module-info.java files for the modules and update their documentation on how to use their libraries in a Java module environment.
If the library you are trying to use is incompatible with the Java module system when used as a module, then you could try making your project non-modular by deleting module-info.java from your project and adding appropriate command-line switches. To understand how to do this, refer to documentation on non-modular projects at openjfx.io.
I'm having a very odd issue which I cannot explain.
I've made an artifact using gitlab ci, which I'm now importing as a dependency in another project using maven.
When I import this into the new project, I get some very strange behaviour in regards to the classes in the imported dependency. These behaviours are as follows:
In Java files (Test.java), the package is found and Intellij reports no issues. I can even navigate to the source code in the library.
In Kotlin files, Intellij complains that this package cannot be found. I can't navigate to the source code as the IDE says "unresolved reference". If I do a maven artifact search, it is found but adding it makes no difference as the dependency is already in my project.
maven compile/package also complains that this package cannot be found
The dependency is definitely present:
I've tried the following:
Reimporting maven projects
Invalidating caches
Changing java versions, 8 - 11
The artifact is written in java 11 if that makes any difference.
Please help, this is driving me crazy.
Thanks to those that answered!
After a long 24 hours of debugging, it turns out the issue is related to how intellij & maven look for packages in dependencies.
I was compiling with the spring-boot-maven-plugin which was building the jar with a top BOOT-INF directory, and the package structure below this.
This meant both intellij and maven were confused as they seemed to be able to find the package but not build it.
I've since removed the plugin and left now just compile with the kotlin-maven-plugin which has the package structure at the top level of the jar.
Now when I import into a project, the project can find and compile this dependency.
So here is a quick rundown of my situation:
I have two Java projects: one in Java 8 (so not modular) and one in Java 11 that is modular.
The modular/not-modular issue may not be relevant but for the sake of clarity, I've stated it.
For reference, the Java 8 is a game library I made, and the Java 11 is the game implementation I'm making.
I need to reference the Java 8 library from my Java 11 game project.
Both projects are Maven projects, and I have my dependency defined in my game's POM file.
I'm using latest version of Eclipse (2020-03 4.15.0) and Maven 3.6.3 with Java version 11.0.7 OracleJDK.
My Problem:
My understanding is that my Java 8 library project becomes an automatic module. Adding it into my Java 11 game project module-info file works (with a warning about the name being unstable, but no issue) and I can compile my game project code with no issues in Eclipse.
When I attempt to run the game, I get Module <my-library> not found, required by <my-game>. Now, since Maven is managing the dependencies, it should just work.
How can I get my game to run?
I Can Fix It Three Ways...
First I can simply manually add the library project's JAR file (in it's target folder) to the Run Configuration module-path of my game project.
Second, I can delete the library project from my workspace. This means Maven then goes and gets the JAR from the local m2 repo (it's been installed with mvn install). In this situation Maven DOES automatically add the JAR to the Run Configuration module-path correctly.
Third, I can change the version of the library project in it's POM file and like option two, this means it no longer satisfies the dependency and Maven then looks for the JAR in the local m2 repo.
But...
All three of these options seem to me like they should be unnecessary. This feels like a bug with Maven failing to add the in-workspace project dependency to the module path in the Run Configuration in Eclipse.
To be fair, it is a Maven Eclipse plugin feature that automatically detects when one of the in-workspace projects is a dependency and uses that "live" version instead of the m2 repo version. This is very handy for these situations where development on a library is happening in parallel.
But until this bug is fixed (or unless it's not a bug and I'm missing something), this caused me a ton of frustration. I've posted this in hopes of helping anyone else who may be facing the same issue.
Tried to get Eclipse 2018-09 + Patch with Java 11 support, m2e, and junit5 working together.
As recommended in junit5-modular-world example I introduced a second module-info.java under test/java.
The reaction of Eclipse was astonishing to me:
I could not save that file after changing it.
It was saved only by closing Eclipse at all.
However, re-opening, bewildered Eclipse. It cannot show any details of the project hosting multiple module-info.java, just the project name.
Probably Eclipse identifies one project with one Java module, while mvn test compiles and executes obviously a different module than the one created by mvn install.
Experienced a lot of options I can think of. Currently I had to give up and fall back to junit 4.12.
Do you know of a better solution?
A secondary module-info.java in the test source folder is not supported by Eclipse at this time (but its behaviour if you try to do that should probably be improved).
For now, you probably won't need it at all:
Maven puts dependencies that are mentioned in the module-info.java on the module path, all others (e.g. test-only dependencies like junit) on the class path, so they become part of the unnamed module. When tests are compiled, command line options are added, so the test code that is treated as part of the module in the main source folder still can read the unnamed module (by adding --add-reads modulename=ALL-UNNAMED), so junit is visible to the test code.
Eclipse Photon and later also supports this behaviour.
Some background regarding the secondary test module-info.java: maven-compiler-plugin supports this since version 3.8 (see https://www.mail-archive.com/announce#maven.apache.org/msg00866.html, implemented in issue https://issues.apache.org/jira/browse/MCOMPILER-341), but I'm not aware that a matching maven-surefire-plugin has been released, so I think you currently wouldn't be able to run these kinds of tests with maven.
Implementing support for a secondary test module-info.java in Eclipse may be possible, as long as it is a strict superset of of the primary module-info.java in the main source folder, or maybe as long as they specify the same module and their contents would get merged as in the "pro" build tool https://github.com/forax/pro. But nobody has worked on that yet.
What will probably be never supported in Eclipse, is to have a secondary test module-info.java that specifies a different module as Eclipse has the assumption that one java project belongs to only one module. But that shouldn't matter, as these tests can only use public and exported code of the main sources, so they can simply be put into their own maven module.
I'm having hard time to setup springframework code in Intellij.
I git-cloned springframework project from github, and ran ant task to get all the libraries into ivy-cache directory.
I found "spring-framework.ipr" file for intellij project, and opened it.
Unfortunately, some of the libraries are not correctly mapped to the jar files or missing. So I cannot compile the codebase in IDE.
I also tried importing as eclipse project into intellij. Jar file reference seems ok.
But there are compilation errors in OXM module. Some test classes have reference to auto generated classes such as "~.samples.flight.FlightDocument", "~.jaxb.test.FlightType", and they don't exist(ant test goal generates them in target dir).
It seems same problem happens in STS.
I referenced this blog post:
http://blog.springsource.org/2009/03/03/building-spring-3/
Any good idea to setup spring code in intellij?
I use intellij v11.
git branch: 3.1.x
git commit: e8fc90ce3e4554f14eaa86ce05591249d3fe62fa
Compilation error example:
.../org.springframework.oxm/src/test/java/org/springframework/oxm/xmlbeans/XmlBeansMarshaller Tests.java
Error:(29,42) package org.springframework.samples.flight does not exist
Error:(30,42) package org.springframework.samples.flight does not exist
Error:(44,9) cannot find symbol class FlightsDocument
Error:(44,58) package FlightsDocument does not exist
....
Thanks,
problem solved.
"spring-framework.ipr" is the one for intellij.
lesson learned:
simply wrong version of junit was referenced in spring-framework.ipr file.
when ant build failed middle of the test, subsequent module won't be built. so, required libraries won't be downloaded into ivy-cache/repository.
"ant jar" goal will not download test related libraries since the goal doesn't run tests
After all the tests passed and manually fixed junit reference, intellij finally has no errors.