I used eclipse with jdk 8 to export to jar. Yet i still get this error when start my server sfs
Exception in thread "main" java.lang.UnsupportedClassVersionError: sfs2x/extension/mmo/MMORoomDemoExtension$NPCData 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
Could someone tell me how to fix.
I tried to uninstalled all java and install jdk8 only. But nothing change.
I had a similar problem, what fixed it for me was making sure that jdk8 was selected as the build jdk for that project (right click on your project in Eclipse and click on properties -> Java build path -> JRE System Libraries -> Workspace Default JRE, make ure that jdk8 is selected) and then recompiling. I was able to delete all .class files before recompiling as well, but that may be difficult if this is a project.
Best of luck.
Related
I’m trying to update my JavaFX project to be compatible with JRE 13 (until now it was set up to use JRE 1.8). I’m developing with Eclipse 2020-03, using a Mac.
The first big issue I’ve had to deal with is the migration from the included JavaFX libraries in JDK 1.8 to having to import JavaFX (14) as an external package for JDK 13.
The second issue is migration from using the classpath to using the modulepath. I’m new to the module path, so what I say about it may not make sense, but my current setup now is this:
modulepath:
<list of other .jar files>
JRE System Library [Java SE 13 [13.0.2]]
JavaFX 14
<list of .jar files I downloaded, including javafx-swt, javafx.base, javafx.controls, javafx.fxml, javafx.graphics, javafx.media, javafx.swing, javafx.web>
<I created a User Library from the above listed .jar’s>
Finally, all the compiler errors are now gone (I had to recompile some of the external .jar files I downloaded so there weren’t any split packages), but when I build and run the application class nothing happens.
Checking the Mac system console, the below output seems to reference why the app is not starting, but I checked he JDK path and the referenced java executable does exist.
com.apple.xpc.launchd[1] (com.apple.xpc.launchd.domain.pid.java.40558): Failed to bootstrap path: path = /Library/Java/JavaVirtualMachines/jdk-13.0.2.jdk/Contents/Home/bin/java, error = 2: No such file or directory
What is happening here? If you need more info about my project config, comment and I can add details.
I'm trying to use NetBeans for a JDBC project. However, I'm getting runtime errors when I try to compile. I decided to try a "hello world" project and I couldn't get that to run also. I'm in NetBeans 9.0 with Java JDK 10.0.2.
Error Message:
Exception in thread "main" java.lang.RuntimeException:
at javaapplication2.JavaApplication2.main(JavaApplication2.java:1)
C:\Users\James\AppData\Local\NetBeans\Cache\dev\executor-snippets\run.xml:111: The following error occurred while executing this line:
C:\Users\James\AppData\Local\NetBeans\Cache\dev\executor-snippets\run.xml:68: Java returned: 1
BUILD FAILED (total time: 1 second)
xml debug:<call-java classname="#{classname}" classpath="#{classpath}" modulename="#{modulename}" modulepath="#{modulepath}">
package javaapplication2;
public class JavaApplication2 {
public static void main(String[] args) {
System.out.println("Hello");
}
}
It is very easy, your JDK version is not 100 % compatible; use version 8.2, which is the most stable for Arduino and others.
To change platforms without deleting the existing one, simply go to Tools / Java Platforms / click on the button add Platforms.
Download/install JDK major version number the same as NetBeans.
i.e. If You have NetBeans 9 version, but your JDK is version 10,So try use NetBeans 10 version... or download/install JDK 9 (the same as NetBeans).
Create new java platform for new jdk installation.
Open netbeans menubar->tools->Java Platforms->Add Platform Specify the folder that contains the Java platform as well as the sources and Javadoc needed for debugging.
Set new java platform to your project
Right click on project ->properties->Libraries->Java Platform->select the jdk version that same as NetBeans.
Select source format of your project
Right click on project ->properties->Sources->Sources/binary format->select the jdk version that same as NetBeans.
If it still give same error,Open the project properties, select the Build-Compiling, uncheck "Compile on save" and rerun the application. This will make sure all your source code becomes recompiled before running it.
I don't know what problem with my JasperReports report, when I try to add new datasource in iReport, I got this error
Unsupported major.minor version 51.0
(unable to load class com.foundation.service.datasource.JsDataSourceService).
I followed all the answer on StackOverflow, and I changed the complicance level to 1.7, jre also is set to jre7 too, I already check the environment variable
JAVA_HOME: C:\Program Files\Java\jdk1.7.0_25,
but still got this error. Please help me to fix that!
This happened to me also - I had recently installed JDK 7, which is what that incompatible class version is. The root cause for me was that I was compiling my jasper reports using the maven plugin, which does not have a way to set -target 1.6. So, my solution was to run maven from a shell in which I'd made the following change:
export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Versions/1.6/Home
do mvn --version to confirm you now get a 1.6 Javac instead of the 1.7. That's a more brute force way of setting the target class format.
I'm on OS X 10.8 - if you aren't, you may have to change that slightly, but hopefully the idea helps.
Your environment variable is already correct/set to jdk1.7.0_25.
I bet the issue is with your IDE.
If you're using Eclipse, go to Configure Build Path
Edit existing JRE System Library (previously set to jdk1.6)
Choose Alternate JRE
Browse to Installed JREs... (normally in C:/Program Files/Java..)
Click Finish
I created a Drools project in Eclipse (Indigo) configured to use JRE 1.7. But I get an error pointing to my .drl file:
com/sample/DroolsTest$Message : Unsupported major.minor version 51.0
The com.sample.DroolsTest.Message class is imported by the .drl file. The Drools runtime was 5.2.1 (also tried with 5.3.0.Final).
Any help would be appreciated. Thanks.
This exception doesn't seem to have to do anything with Drools in particular, but is a generic Java error. It occurs if you try to execute a Java class with a JRE that is older than the JDK that was used to compile it. For example, if you compiled the class with a JDK7 and then tried to execute it with a JDK6, you would get this error.
Just to detail above answer and comment. I had both JRE6 and JRE7 installed, with JRE7 being the default. I had to do two things to remove the error from the drools sample project.
Set the JRE for the project to 1.6
Project properties->Java Build Path->Libraries. Remove JRE System Library 1.7 and Add Library->JRE System Library->Alternate JRE->JRE6
Set the compiler compliance level for the project at 1.6.
Project properties->Java Compiler->check Enable Project specific settings and set Compiler compliance level at 1.6.
I'm running java 1.6 in Eclipse on my Intel Mac. I'm using the 1.6.0 version under System/Library/Frameworks and set the default compiler to this in Eclipse.
How do I attach the source code?
First, I downloaded the 1.6 source from oracle, thinking I could attach that 'cause the installed 1.6 didn't have source.
When I click a java class to get the Source Code Editor, there are problems:
first, the top line says Compiled from File.java (version 1.5 : 49.0, super bit)
most important, when I attach the 1.6 source jar file, it gets an error:
An error has occurred. See error log for more details.
Unable to create resource org.eclipse.ui.internal.misc.ExternalProgramImageDescriptor#50417ba8
This also appears in the error log:
java.lang.ClassNotFoundException: org.eclipse.ui.internal.views.log.LogView
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:506)
The Eclipse version is: Eclipse Java EE IDE for Web Developers.
Version: Helios Service Release 2
Build id: 20110218-0911
When I click for installation details, I get:
An internal error occurred during: "Fetching children of _SELF_".
Registry Directory not available: /Users/rfrail/Downloads/eclipse 2/p2/org.eclipse.equinox.p2.engine/profileRegistry.
I'm running Eclipse from my Download directory (it's worked fine in the past); however, there are 2 folders for Eclipse:
eclipse, and
eclipse 2.
So that looks like a source of confusion right there. Eclipse operates fine otherwise.
Can you help, please?
http://java.decompiler.free.fr/ is your answer
it has an eclipse plugin which decompiles code in place