I'm running into problems trying to use The Grinder. The tutorial on the site tells me to run "StartAgent.bat", which looks like this:
call "C:\Documents and Settings\dkeller\Desktop\Grinder\setGrinderEnv.bat"
java -cp %CLASSPATH% net.grinder.Grinder %GRINDERPROPERTIES%
When I open the Command Console and try to run it, I get this error:
"C:\Documents and Settings\dkeller\Desktop\Grinder>java -cp "C:\Documents and Settings\dkeller\My Documents\grinder-3.4"\lib\grinder.jar;"C:\Documents and Settings\dkeller\My Documents\grinder-3.4"\lib\grinder.jar;"C:\Documents and Settings\dkeller\My Documents\grinder-3.4"\lib\grinder.jar;"C:\Documents and Settings\dkeller\My Documents\grinder-3.4"\lib\grinder.jar; net.grinder.Grinder "C:\jython2.5.2\grinder.properties"
Exception in thread "main" java.lang.UnsupportedClassVersionError: net/grinder/G
rinder (Unsupported major.minor version 49.0)
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)"
Yikes. Not totally sure what the problem is. Thinking it might be an issue with java versions, I made sure to update to the latest, but I'm not sure if it worked correctly. Here are some commands I ran, so you can see what I mean.
"java -version" returns
java version "1.4.2_03"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_03-b02)
Java HotSpot(TM) Client VM (build 1.4.2_03-b02, mixed mode)
and "javac -version" returns
javac 1.6.0_26
Any help would be much appreciated, as I'm not sure what to try next.
Looks like your PATH environment variable is the problem. It's probably easiest just to edit that to have your JDK's bin directory in the PATH of the "user" part of the environment variables, so it comes before anything else which might contain java.exe.
Basically when you run java -version, you want it to show the same version number as javac -version.
Alternatively, you might consider uninstalling Java 1.4.2 unless you're still using it for something else...
Related
I cannot debug Java SE 6 using Eclipse 2022-12, It throws the following exception:
java.lang.UnsupportedClassVersionError: org/eclipse/jdt/launching/internal/javaagent/Premain : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(Unknown Source)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(Unknown Source)
at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(Unknown Source)
FATAL ERROR in native method: processing of -javaagent failed
Exception in thread "main"
However, I can run this project (Java SE 6) without any problem. I can also run and debug another Java SE 7 normally.
It's same as the problem posted here: https://www.eclipse.org/forums/index.php/mv/msg/1112218/1856754/
It's maybe happen since this change: https://github.com/eclipse-jdt/eclipse.jdt.debug/issues/61
So. is there a way to debug Java SE 6 using eclipse 2022-12, thank you.
TL;DR
Downgrade your Eclipse (we are using 2022-03)
Double check Java version after that
Long story
A colleague had this problem today and after some tinkering we've got it to work. His Eclipse was also stopping at a ghost breakpoint. He had never ever worked on that project and we had cleaned up everything, but even then, it would stop at a breakpoint and break with the mentioned error.
After reading the links in this question, now I understand why this worked, but the second item was very unexpected:
I was on 2022-03 where it was working, so we downgraded his Eclipse to 2022-03 as well. As you pointed out, it seems they have made a change that created this bug during debug mode for Java 1.6.
After that, we double checked Java version everywhere and we found out that the Java 1.6 that was showing up on Eclipse was actually a Java 11 (it was written like "JavaSE-1.6 (jdk 11)"), so we forced it to use from a new Java 1.6 location. I assume Eclipse mixed up something, because I think it runs on Java 11.
After that, debug was working again.
I am stuck on the following error. I don't know what type of error it is. What should I do?
C:\Users\shehzad\Desktop\Software>java -jar Untitled.jar
Exception in thread "main" java.lang.UnsupportedClassVersionError: FrontEnd/MainWindow : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:56)
Scenario is: I developed software that works fine in Ubuntu 14.04 Lts. It's JAR also works in Ubuntu, but when I tried this JAR
in Windows 7 it shows the above error.
Ubuntu Java version: 1.8.0_101
Windows Java version: 1.7.0_79
class version 52.0 means it requires Java 8 to run. You should for security reasons update your Windows Java anyway, so its time to go to Java 8. If you need Java 7 for something you can keep it as a private installation, but make sure the "javapath" as configured by the registry points to Java 8.
You can also start in a command window or via explorer link the right Java.exe without installing it as public version like this:
"c:\Program Files\java\jdk_1.8.0_102\bin\javaw.exe" -jar app.jar
Your jar file is compiled using 8u101 (major.minor version 52.0) and your trying to run on 7u79. Hence you end up in Unsupported major.minor version 52.0.upgrade your java to 8u101.
I am trying to run a java based java profiler to find out what uses up resources on my java application on my dedicated machine. The profiler I am trying to use is called warmroast.
I get the following error from running.
java -jar warmroast.jar
Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/tools/attach/AttachNotSupportedException
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at sun.launcher.LauncherHelper.validateMainClass(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Caused by: java.lang.ClassNotFoundException: com.sun.tools.attach.AttachNotSupportedException
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 6 more
I think this error is caused by running the file with jre instead of jdk.
I have installed java-1.7.0-openjdk-1.7.0.55-2.4.7.1.el6_5.x86 as a yum package.
[root# ~]# java -version
java version "1.7.0_55"
OpenJDK Runtime Environment (rhel-2.4.7.1.el6_5-x86_64 u55-b13)
OpenJDK 64-Bit Server VM (build 24.51-b03, mixed mode)
I think to fix this problem, I will need to run the jar file using jdk. Is there some kind of a jdk path to the jdk bin file? If so, what is it in centos? I've googled for a while and came up with dozens of wrong paths. I feel stupid because I think jre is a part of jdk and jdk is only using for compiling stuff and I don't think you can run files with jdk...
...
...
The class that could not be found is in tools.jar in your JDK. This library is usually not automatically on the class path, even if you use JDK instead of JRE.
According to the documentation, on Linux warmroast should be started as follows (replace PATH_TO_JDK with the path to your JDK):
java -Djava.library.path=PATH_TO_JDK/jre/bin -cp PATH_TO_JDK/lib/tools.jar:warmroast-1.0.0-SNAPSHOT.jar com.sk89q.warmroast.WarmRoast --thread "Server thread"
Here, tools.jar is manually added to the classpath.
Basically what I want to do is create a PDF from a iReport jrxml or jasper file.
The idea is to use this for reports over the net and the best solution I managed to find was to use a program like jasperstarter and then run the report with a connection to MSSQL database.
To get the connection going I had to download the latest net.sourceforge.jtds.jdbc.Driver.
The report works fine using iReport 5.1 but when I do follow the instructions from jasperstarter I get an "java.lang.UnsupportedClassVersionError" response.
jasperstarter command
jasperstarter pr -t generic -f pdf -i test_report.jasper -o test -u username -p password --db-driver net.sourceforge.jtds.jdbc.Driver --db-url jdbc:jtds:sqlserver://LOCAL-PC/Demo_DB
output
Exception in thread "main" java.lang.UnsupportedClassVersionError: net/sourcefor
ge/jtds/jdbc/Driver : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(Unknown Source)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at de.cenote.jasperstarter.Db.getConnection(Db.java:69)
at de.cenote.jasperstarter.Report.fill(Report.java:220)
at de.cenote.jasperstarter.App.processReport(App.java:222)
at de.cenote.jasperstarter.App.main(App.java:107)
Please advice.
Basically, you are trying to run code that was compiled on / for Java 7 on an older JVM.
That doesn't work.
Either:
run your application on a Java 7 JVM (or later1); i.e. upgrade your Java version,
find a build of the JDTS driver that is suitable for your execution platform, or
find the source for the JDTS driver and build it for your platform.
For more detailed information on this exception and its causes, read:
http://stackoverflow.com/questions/10382929.
1 - Note that even Java 7 is end-of-life now. If you are still running that version of Java you should upgrade.
Make sure you have same JRE and JDK.
If not sure un-install download the latest JDK and try again.
Note that the JDK does install the JRE automatically.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Java error: Bad version number in .class file error when trying to run Cassandra on OS X
I am not sure i am doing anything wrong with this basic hello world program. Have no idea why does this throw errors.
I have saved the file as test.java.
public class test {
public static void main(String[] args) {
System.out.println("Hello!");
}
/*public static void sop(String str) {
System.out.println(str);
}*/
}
When i compile it with javac test.java, it compiles successfully, but when i try to run it by using java test, it gives the following error:
C:\Users\admin\Desktop>java test
Exception in thread "main" java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
The Java bin directory is added in System path. Would appreciate any pointers.
Java directories in the system path are as follows:
C:\Program Files\Java\jdk1.6.0_31\bin;C:\Program Files\Java\jre6\lib;
The java/javac versions:
C:\Users\admin\Desktop>java -version
java version "1.5.0_12"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_12-b04)
Java HotSpot(TM) Client VM (build 1.5.0_12-b04, mixed mode, sharing)
C:\Users\admin\Desktop>javac -version
javac 1.6.0_31
Thanks.
Your java compiler is version 1.6.0 and your java executable environment is version 1.5.0.
The error is to tell you that your java executable to too new for the java executable environment.
To solve your problem you need to update your java environment (or downgrade your java compiler).
It could also be that your test class is improperly titled.
Class names should be capitalized according the ANSI standard.