Ошибка: A JNI error has occurred, please check your installation and try again
Скомпилировал проект при помощи Maven при запуске jar файла через терминал выдает ошибку:
Error: A JNI error has occurred, please check your installation and try again Exception in thread "main" java.lang.NoClassDefFoundError: org/eclipse/jetty/server/Connector
Суть в том, что в Еклипсе проект запускается и успешно работает. Вот код главного класса:
EventServer < public static void main(String[] args) < Server server = new Server(); ServerConnector connector = new ServerConnector(server); connector.setPort(8081); server.addConnector(connector); // Setup the basic application "context" for this application at "/" // This is also known as the handler tree (in jetty speak) ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS); context.setContextPath("/"); server.setHandler(context); try < // Initialize javax.websocket layer ServerContainer wscontainer = WebSocketServerContainerInitializer.configureContext(context); // Add WebSocket endpoint to javax.websocket layer wscontainer.addEndpoint(EventSocket.class); server.start(); server.dump(System.err); server.join(); >catch (Throwable t) < t.printStackTrace(System.err); >> >
Error «A JNI error has occurred. Please check your installation and try again in Eclipse x86 Windows 8.1»
The above code works perfectly on my friend’s laptop and throws this error on my laptop. I have running the code on Eclipse v4.2 (Juno) using Java 7. I have also tested and run a lot of Java programs on my laptop all works well. This is the only program which gives such an error. How can I fix this problem?
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asked Mar 13, 2014 at 14:09
Jash Parekh Jash Parekh
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I faced the same problem with jdk-8u144-windows-x64.exe in Windows 10
Sep 14, 2017 at 12:02
Clean project solved this issue for me
Oct 16, 2017 at 9:06
Mar 8, 2019 at 7:11
«please check your installation» — my installation of what?
May 1, 2019 at 22:07
Your installation of Eclipse + any plugins. Look in the Eclipse logfile for clues.
Oct 17, 2020 at 2:03
42 Answers 42
I have been having this problem for a while, but now I have figured it out.
It turns out that Java JDK 12 has both the JRE and the JDK inside the bin folder of the Java 12 JDK. (I have always believed that JRE and JDK are different application, but it turns out things have changed.)
My problem was that I had Java JDK 12 installed on my computer. At the same time, I had Java 8 (JRE) Installed on my computer. So my computer was getting confused.
With my command prompt environment set up to run Java and Javac commands:
I typed the follow commands:
java -version
This gave me Java 8.
After that, I typed:
javac -version
This gave me Java 12.
In other words, my program is getting compiled with Java 12 and I am trying to run with Java 8.
To solve the problem, I uninstalled Java 8 JRE from my computer.
I went back to command prompt to check if «java -version» and «javac -version» was returning the same version number, and yes, it was returning Java 12.
I tried recompiling my program again, and running it. It worked!!
This worked for me but I left Java 8 on the system and I had to change the properties of the project to use Java 12. No more JNI error.
Sep 30, 2019 at 14:47
You do not need to uninstall java 8 , just configure your java versions on your system sudo update-alternatives —config javac; sudo update-alternatives —config java
May 31, 2020 at 9:12
@NicoleFinnie Too complicated and took much work.
Jan 14, 2022 at 16:44
«I have always believed that JRE and JDK are different application, but it turns out things have changed.» — Nope. Nothing has changed. A JDK has always included a JRE. All the way back to the Java 1.1 days. JREs and JDKs are different distributions not different applications.
May 16, 2022 at 1:35
Solution 1: Right-click on the class that contains the main method. Click on «Run As». Click on «Java Application». The keyboard shortcut is: Shift + Alt + X , J (while holding Shift and Alt , press X ; then release Shift and Alt and press J ).
Solution 2: As Professor mentioned, please make sure that java -version and javac -version are the same.
Note: Solution 1 is a quick fix and worked for me and a few other people. It may or may not work for you. I think Solution 2 is the proper way to solve it.
Your Short Answer Helped. Only I need to write a new application name and select my main function containing class. It worked like charm.
Feb 4, 2017 at 14:12
How do you resolve the error if the java file is a part of an android project on android studio
Jun 2, 2018 at 10:33
On the project level, I referenced JRE library to 1.8.xx and worked for me.Thanks
Sep 20, 2019 at 10:30
Just worked for me when I deleted all project configuration files. Which is equivalent to create a new project.
Sep 21, 2019 at 15:26
it seems that this occurs when eclipse itself uses different JDK from current Java Project, after checked -Djava.library.path of Java process started by Eclipse ant launcher, dll path of Eclipse JRE is placed first, Ant’s one (used by launching configuration) is placed last, so I think this is a bug of Eclipse Ant launcher plugin.
Jun 4, 2020 at 4:06
Running the jar from command line by:
C:\folder\where\jar\stored>java -jar JarName.jar
I got information which made the problem clearer:
main/Main has been compiled by a more recent version of the Java Runtime
In this case, the jar was compiled with a version newer than jre supports.
answered Nov 29, 2018 at 10:04
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How do you fix this?
Apr 4, 2020 at 20:29
@Atnas I changed the compiler jdk compliance. In Eclipse its under project properties > java compiler > jdk compliance
Apr 5, 2020 at 4:40
@c0der this solved my problem thanks!
Oct 5, 2021 at 6:02
Please review Should we edit a question to transcribe code from an image to text? and Why not upload images of code/errors when asking a question? (e.g., «Images should only be used to illustrate problems thatcan’t be made clear in any other way,such as to provide screenshots of a user interface.») and take the appropriate action (it covers answers as well).
May 23, 2022 at 20:10
Error: A JNI error has occurred, please check your installation and try again in Eclipse
Solution: Check your package name as it may be colliding with the package name in Java. Simply change the package name to resolve your issue. 🙂
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answered Aug 16, 2017 at 12:01
user8472395 user8472395
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but what should I check ?
Oct 23, 2019 at 2:56
check for «java» or «gradle» name
May 2, 2021 at 1:22
I solved it by changing my ‘Compiler compliance level’. In Eclipse:
Menu Window → Preferences → Java → Compiler.
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answered Aug 9, 2019 at 16:52
juancarlosun juancarlosun
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This worked for me. The «Run As’ fix listed above didn’t help.
Mar 25, 2020 at 14:52
Thanks! The issue for me was that I previously had Java 12 installed and then went to Java 1.8, but Eclipse didn’t pick up on the Java version change for the compliance level.
Oct 25, 2021 at 15:46
I had similar issues when using ‘java’ at the beginning of the package name, e.g. java.jem.pc
Check your console output, I was receiving:
Exception in thread "main" java.lang.SecurityException: Prohibited package name: java.jem.pc
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answered Oct 19, 2016 at 23:02
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Worked fine in my case. I was using package java, now updated and found working. Thanks
Nov 2, 2017 at 14:00
I faced a similar problem with a project, in IntelliJ with Maven dependencies.
I solved it changing the dependencies scope from provided to compile.
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answered Aug 22, 2018 at 14:41
Salvador Vigo Salvador Vigo
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In my case the issue was caused by the JDK version. To solve this I suggest to go into your POM file and check the 1.7.
Afterwards, check the Java version in your cmd (Windows) or terminal (OS X or Linux) by typing: java -version.
Compare the version shown in the terminal/command prompt with what you have in your POM file. Make sure they are the same. Then run your project again.
You can check the console first to see the actual error message and then proceed by looking for answers for that error.
My console shows the error NoClassDefFound for the class jcommander.
Your error will probably be different from mine. The cause of my error is that the class jcommander is not in my M2 repository, so I just have to add that dependency in my pom.xml file. You can check if all the class dependencies are all declared and added in your current configuration and project build.
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answered Nov 23, 2016 at 9:11
Miguel Ormita Miguel Ormita
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I also faced the same issue. By looking at the console that’s saying
the solution is: Check your package name of your project.
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answered Jun 12, 2017 at 15:13
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This solution works for me, thumbs up
Dec 5, 2021 at 13:02
I have found that adding these lines of code to the pom.xml file of a Maven project solves similar issues for me:
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answered Sep 13, 2018 at 5:58
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This worked for me 🙂
Jun 24 at 1:57
I was facing the same issue and in my case the compiler compliance level was selected as 14 in my Eclipse settings. In order to fix it, I changed it to the version of JDK on my machine i.e 1.8 and recompiled the project.
Check your console. It says java.lang.SecurityException issue. Change your ‘package name’. I changed my package name from ‘java.assessment’ to ‘assesment’ and it worked for me. If somebody knows the root cause , let me know please.
I experienced the same issue, however in my case it was due to the Configuration settings in IntelliJ IDEA.
Even though the project SDK (File -> Project Structure) was set to Java 11, the JRE in the Run/Debug Configurations (Run -> Edit Configurations) was set to Java 8. After changing that to Java 11, it worked like a charm.
What exact error message did you get? Please respond by editing (changing) your answer, not here in comments (without «Edit:», «Update:», or similar — the answer should appear as if it was written today).
May 23, 2022 at 20:14
I faced a similar problem and then got the solution in the package name.
I kept the package name as java.basics. In the console I got a hint for that as it clearly said «Prohibited package name». So I changed the package name and it worked.
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answered Apr 9, 2016 at 20:20
H S Rathore H S Rathore
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Possible solution
If none of these solutions worked for you then try this. I finally got mine working by deleting the two folders «.metadata» and «.recommenders» in the workspace folder.
You can find your workspace folder path by clicking on menu File → Switch Workspace → Other in the Eclipse application’s toolbar.
Now I am a complete noob crying my way through an software engineering degree at San Jose State University. So I am just sharing what worked for me without knowing much knowledge of why exactly.
I do not know what harm or headaches, or even if both aforementioned folders needed to be deleted. But in the end, it worked for me and it seems the application just recreates fresh versions of those folders anyway.
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answered Feb 28, 2018 at 4:55
Muhammad Soroya Muhammad Soroya
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Error/Issue:
While trying to run my application as a Java application or as a Spring Boot application, I am getting below error
A JNI error has occurred, please check your installation and try again. A Java exception has occurred.
As well as getting this error in the console:
Exception in thread «main» java.lang.UnsupportedClassVersionError: com/example/demo/IocApplication has been compiled by a more recent version of the Java Runtime (class file version 55.0). This version of the Java Runtime only recognizes class file versions up to 52.0`
What is the root cause?
The reason for this error is that
the code is getting compiled on a higher version. In my case, it is version 11. and
the code is getting executed on a lower version. In my case it is version 8.
I.e., Java (JDK) compiled code on 11, whereas the JRE version is 8.
Where did I configure JDK 11 and JRE 8?
I am using SpringToolSuite (STS). When I created the project, the JRE System library was in the build path, which got added as the default JRE library version of 8 (1.8). But when I go to the project → Properties → Java Compiler → Compiler Compliance Level, it is by default having a selected version of 11
Both javac and java versions are the same. If different, you will get this error.
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answered Oct 3, 2021 at 4:28
Rohit Chaurasiya Rohit Chaurasiya
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What do you mean by «Just check small step»? Can you elaborate?
May 23, 2022 at 21:25
My issue came from trying to disable the Maven nature from my project and then deleting the pom.xml file. This is bad, very bad, don’t do this. If you do, change it back to a Maven project and hopefully you can either restore your old pom.xml file or create a new one. As soon as I did that, it worked again.
EDIT: I recently ran across this problem again and this time it was because I had duplicate libraries in my classpath. The one Maven added (which started with /M2_REPO/. and then one I had added (which I should not have done). Even though Eclipse was reporting that it could not find the class, the actual problem was that I had given it two libraries with the same class and it didn’t know which one to use. Once I removed the second reference, it worked.
answered Mar 23, 2018 at 19:11
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What do you mean by «disable the Maven nature»?
May 23, 2022 at 0:59
You can try: right click on the project and then click clean. After this run the project.
It works for me.
answered Jun 24, 2018 at 17:32
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In my project I had changed my Maven POM file and removed the entry for maven-jar-plugin.
When you build a JAR file whose purpose is to be executable, you need to include this so that certain entries get written into the manifest. I opened the old project, copied that entry (with some modifications for project name) and it worked.
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answered Oct 19, 2017 at 19:36
Eric Forte Eric Forte
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I think this happens because the name of your class is the same name of another class in the JDK. Help Eclipse to determine which one you are trying to run by selecting the package your class is in. Go to run configuration, select the project and the main class.
When you press the search button to select the main class, you will find options that have the same name but different package, select your class.
There was no information in my console so that sent me searching for additional solutions and found these — unique to the solutions presented here. I encountered this with Eclipse v4.7 (Oxygen) trying to run an old Ant build on a project.
Cause 1
I had configured Eclipse to use an external Ant install which was version 1.10.2 which apparently had classes in it that were compiled with JDK 9. In Eclipse I got the JNI error described above (running the Ant build at the command line gave me the renowned ‘unsupported major.minor version’ error — the Java I was using on the system was JDK 8).
The solution was to roll back to the embedded Eclipse version of Ant being 1.10.1. I verified this as the correct solution by downloading Ant 1.10.1 separately and reconfiguring Eclipse to use the new 1.10.1 externally and it still worked.
Cause 2
This can also happen when you have the Ant Runtime settings configured incorrectly in Eclipse’s Preferences. Depending on the version of Ant you’re running you will need to add the tools.jar file from the appropriate JDK to the classpath used for the Ant Runtime (Home Entries). More specifically, without a proper configuration, Eclipse will complain when launching an Ant target that the JRE version is less than a particular required version.
Essentially, ‘proper configuration’ means aligning each of the configuration items in Eclipse for running Ant so that they all work together. This involves the Ant Runtime Home entry (must point to an Ant version that is compatible with your chosen JDK — you can’t run Ant with JDK 8 when it was compiled against JDK 9); specifying the tools.jar that belongs to the JDK you want to run Ant with in the Ant Runtime settings; and lastly setting the JRE environment of your build script to the JDK you want to run Ant with in the External Tools Configuration.
All three of these settings need to agree to avoid the error described above. You’ll also need to consider the attributes used in your javac tag to ensure the JDK you’re using is capable of executing as you’ve directed (i.e., JDK 7 can’t compile code using source and target version 8).
Moreover
If you’re really just trying to run an Ant build script to compile code to an older JDK (e.g., less than 8 for Oxygen), this article helped gain access to run Ant against an older JDK. There are Ant plugin replacements for a handful of versions of Eclipse, the instructions are brief and getting the correct plugin version for your particular Eclipse is important.
Or more simply you can use this very good solution to do your legacy compile which doesn’t require replacing your Eclipse plugin, but instead changing the javac tag in your build script (while using the latest JDK).
Java: “A JNI error has occurred, please check your installation …” – How to fix this error!
You have encountered this JNI Error error message? Don’t panic! The problem can usually be solved quite quickly – and here you can find out how.
Have you encountered this error message or popup?
Error: A JNI error has occurred, please check your installation and try again
The problem comes from the fact that your JRE (Java Runtime Enviroment), that is your installed Java version and your JDK (Java Development Kit) do not work together correctly.
Now there are several possible solutions for you. Just choose the scenario that applies to you:
JNI Error in Windows CMD
The problem can occur if you want to call a .jar file via command line (Windows CMD), e.g. via the command java -jar File.jar or if you have compiled your program with Eclipse before.
To fix the error, you need to adjust the environment variables for Java.
To do this, type “environment variable” in your Windows search and open the “Edit System Environment Variables” item. In this window you click on “Environment variables…”.
The “Environment variables” window opens. There you select the variable “Path” in the lower window “System variables” and click on “Edit…”.
There you look for the line where the installation path of your Java JDK is stored. In my case this is under C:\Program Files\Java\jdk-13.0.1\bin.
If you do not have this entry, you can add it by clicking the “New” button.
Select the line with the Java JDK and click on “Move up” until the entry is at the top. Done!
Now you have to close and reopen the Windows-CMD once and the error should be fixed.
JNI Error in Eclipse
In Eclipse the problem can also be the JDK and JRE version. But first see if it might be a simpler problem:
Maybe you have named one of your packages identically to a Java internal package (e.g. java). Try to rename your package – this can be the simple solution.
If the problem is not fixed I navigate to your Eclipse workspace and compile your main file manually in the Windows CMD using the following command: javac Main.java . Then you can run the file manually with java Main . If this works, it is probably due to the JDK and JRE versions in Eclipse. Reinstalling Eclipse may help.
JNI Error when starting a Minecraft Server
If you try to start your Minecraft server via the official server.jar (error occurs since version 1.17), you may get this error message:
Download the latest Java JDK version as .exe file (“x64 Installer”) and install by clicking on the .jar file
Now the server should start again
JNI Error in Minecraft TLauncher
This error message can also appear when launching the Minecraft TLauncher.
Download the latest Java JDK version as .zip archive (“x64 Compressed Archive”) (see screenshot)
Right-click on the downloaded file and click “Extract here”.
Copy the unzipped folder to the directory C:\Program Files\Java
Launch your Minecraft TLauncher and click on the gear in the bottom right corner
Click at “Java path” on “Browse…” and choose C:\Program Files\Java\jdkX\bin\javaw.exe (replace the X by the name of your JDK folder).
Save everything – now the game should start again
Java JNI error message still appears?
Restart your computer
Uninstall old Java versions under Control Panel > Programs > Programs and Features and install the latest Java JRE and Java SDK.
I hope that you were able to fix the JNI error with the help of this post. If this is still not the case, feel free to write me a comment.
What did you think of this post?
A JNI error has occurred, please check your installation and try again при компиляции java программы
Многие новички, которые изучают программирование на Java при компиляции могут столкнуться с ошибкой «A JNI error has occurred, please check your installation and try again». Ошибка выскакивает даже если запускать совсем простой код типа «hello world!» как в примере ниже.
Пример простого кода Hello World!
Обычно компиляция проходит, но созданный класс не интерпретируется. У большинства пользователей ошибка появляется из-за следующих двух моментов:
Неправильные пути в переменных средах;
Вы компилируете файл более новой версией Java, а запустить пытаетесь на более ранней. Например компилировали при помощи Java 10, а запускаете на Java 9.
Как исправить ошибки при запуске и компиляции?
Первое, что следует проверить – пути в переменных средах. По списку первым например стоит путь:
Операционная система компьютера находит екзешник «java.exe» и первым делом смотрит в «..\javapath» и останавливает поиск. Вам нужен файл что лежит в «…jdk\bin». В переменных средах сначала нужно поставить \jdk\bin, а потом уже \javapath. В конечном результате путь должен быть примерно такой:
Во втором случае всё еще проще. Если вы компилируете используя более позднюю версию Java Runtime 54, то соответственно и запуск нужно производить в аналогичной версии. Сама строчка «hello has been compiled by a more recent version of the Java Runtime (class file version 54.0), this version of the Java Runtime only recognizes class file versions up to 53.0» как раз говорит нам об этом. Проверить это можно вбив фразу в тот же Гугл Переводчик.
Compiled by a more recent version of the Java Runtime
Выводы
Как видим с ошибкой» A JNI error has occurred, please check your installation and try again» при компиляции Java программы в основном сталкиваются новички. Решить проблему можно проверив версии Java при компиляции и запуске файлов программы. А так же просмотреть корректность путей к «\jdk\bin» и «\javapath». Напишите в комментариях помогло ли вам решение и удалось ли запустить вашу первую программу.
