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[Eclipse not starting]:An error has occured. See the log file null

I'm unable to get my Eclipse Luna running. It was working fine till now and suddenly crashed. Now when i try to start it, I get the error saying:
An error has occured. See the log file null
I tried launching eclipse from terminal and also tried to delete the metadata folder from my workspace but nothing helped me.
Here is the crash log:
org.osgi.framework.BundleException: Error initializing container.
at org.eclipse.osgi.container.SystemModule.init(SystemModule.java:93)
at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle.init(EquinoxBundle.java:209)
at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle.init(EquinoxBundle.java:201)
at org.eclipse.osgi.launch.Equinox.init(Equinox.java:168)
at org.eclipse.core.runtime.adaptor.EclipseStarter.startup(EclipseStarter.java:296)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:231)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603)
at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
Caused by: java.lang.ExceptionInInitializerError
at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle$EquinoxSystemModule.initWorker(EquinoxBundle.java:137)
at org.eclipse.osgi.container.SystemModule.init(SystemModule.java:83)
... 12 more
Caused by: java.security.ProviderException: setSeed() failed
at sun.security.provider.NativePRNG$RandomIO.implSetSeed(NativePRNG.java:458)
at sun.security.provider.NativePRNG$RandomIO.access$300(NativePRNG.java:329)
at sun.security.provider.NativePRNG.engineSetSeed(NativePRNG.java:212)
at java.security.SecureRandom.getDefaultPRNG(SecureRandom.java:209)
at java.security.SecureRandom.<init>(SecureRandom.java:190)
at org.eclipse.osgi.internal.framework.UniversalUniqueIdentifier.computeNodeAddress(UniversalUniqueIdentifier.java:127)
at org.eclipse.osgi.internal.framework.UniversalUniqueIdentifier.<clinit>(UniversalUniqueIdentifier.java:35)
... 14 more
Caused by: java.io.IOException: Operation not permitted
at java.io.FileOutputStream.writeBytes(Native Method)
at java.io.FileOutputStream.write(FileOutputStream.java:313)
at sun.security.provider.NativePRNG$RandomIO.implSetSeed(NativePRNG.java:456)
... 20 more

It seems you're using Solaris? This OS has an alternative entropy source called EGD, which needs special protocol to write to, which Sun JDK does not implement...
Can you try adding -Djava.security.egd=/dev/random to the vmargs section of your eclipse.ini.
If you still see the same issue. Make sure your user can write to /dev/random.

I fixed it myself. Few files in my security folder /jre/lib/security had got messed up.
Downloaded latest Java Cryptography Extension (JCE) and put the jars (Download US_export_policy.jar and local_policy.jar) in the security folder. My eclipse works fine now.

UnsatisfiedLinkError when running Jetty9's setUID feature

I just tried to run Jetty 9 as non root users, using setuid feature without success for binding low port numbers.
I enabled the module setuid in the start.ini and added -Djava.library.path=/opt/jetty/lib/setuid
But I have the following stack trace when starting Jetty:
2015-06-09 16:27:27.211:WARN:oejx.XmlConfiguration:main: Config error
at | |
java.lang.reflect.InvocationTargetException in
file:/opt/jetty/etc/jetty-setuid.xml
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.eclipse.jetty.start.Main.invokeMain(Main.java:321)
at org.eclipse.jetty.start.Main.start(Main.java:817)
at org.eclipse.jetty.start.Main.main(Main.java:112) Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.set(XmlConfiguration.java:479)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:411)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:815)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.itemValue(XmlConfiguration.java:1125)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.value(XmlConfiguration.java:1030)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.call(XmlConfiguration.java:721)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:417)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:354)
at org.eclipse.jetty.xml.XmlConfiguration.configure(XmlConfiguration.java:262)
at org.eclipse.jetty.xml.XmlConfiguration$1.run(XmlConfiguration.java:1243)
at java.security.AccessController.doPrivileged(Native Method)
at org.eclipse.jetty.xml.XmlConfiguration.main(XmlConfiguration.java:1174)
... 7 more Caused by: java.lang.UnsatisfiedLinkError: org.eclipse.jetty.setuid.SetUID.getpwnam(Ljava/lang/String;)Lorg/eclipse/jetty/setuid/Passwd;
at org.eclipse.jetty.setuid.SetUID.getpwnam(Native Method)
at org.eclipse.jetty.setuid.SetUIDListener.setUsername(SetUIDListener.java:53)
... 23 more
Those are the only references to this error:
dev.eclipse.org/mhonarc/lists/jetty-users/msg01657.html
groups.google.com/forum/#!topic/dropwizard-user/aap2B_U_QPo
But they are either stopped or do not show the solution.
The source code I found for the setuid package is:
https://github.com/jetty-project/codehaus-jetty-project/blob/master/jetty-setuid/modules/java/src/main/java/org/mortbay/setuid/SetUID.java
Even though I cannot be sure this is the version I am using, given this one is from a org.mortbay package, while the one Jetty 9 uses is an Eclipse one.
I tried setting -Djetty.libsetuid.path in the java args (first try-catch block), either adding the path to the $PATH variable or setting -Djava.library.path (second try-catch block) or copying the so to /lib and, finally, leaving it as it is (third try-catch block). I got the same exception stack in all the cases.
I cannot be sure if Jetty is either not finding the so file or not being able to load it, given that, if I remove all the references to the path (the cases I described latter), I still get the same error message.
I use Java7 to run Jetty.
Edit
I added the following snippet to one of my webapps as as matter of test, given that if the webapp succeed, I would know the problem is not in finding the shared object:
SetUID.setgid(1002);
SetUID.setuid(1002);
Passwd pw = SetUID.getpwuid(1002);
System.setProperty("user.name", pw.getPwName());
System.setProperty("user.home", pw.getPwDir());
I have the same UnsatisfiedLinkError as a result.
Edit2
I tried, instead, the following:
System.load(SetUID.__FILENAME);
SetUID.setgid(1002);
Which got me the following error message:
javax.servlet.ServletException: java.lang.UnsatisfiedLinkError: Native
Library /lib/libsetuid.so already loaded in another classloader
I may conclude, therefore, that the library has been loaded, at least.

Exploring the libsetuid file (nm -D /path/to/the/so), I realized that the so I was using was outdated and was not compatible with Jetty 9, the functions were named as mortbay:
root#root:~/# nm -D libsetuid.so --size-sort | less
0000000000000010 T Java_org_mortbay_setuid_SetUID_setgid
0000000000000010 T Java_org_mortbay_setuid_SetUID_setuid
0000000000000015 T Java_org_mortbay_setuid_SetUID_setumask
0000000000000018 T throwNewJavaSecurityException 0000000000000058 T
throwNewJavaException 000000000000008e T
Java_org_mortbay_setuid_SetUID_setrlimitnofiles 00000000000000a7 T
getJavaMethodId 00000000000000f5 T
Java_org_mortbay_setuid_SetUID_getrlimitnofiles 0000000000000102 T
getJavaFieldInt 0000000000000111 T setJavaFieldInt 0000000000000111 T
setJavaFieldLong 0000000000000121 T setJavaFieldString
00000000000001ba T Java_org_mortbay_setuid_SetUID_getpwuid
00000000000001e5 T Java_org_mortbay_setuid_SetUID_getpwnam
000000000000027e T Java_org_mortbay_setuid_SetUID_getgrgid
000000000000029e T Java_org_mortbay_setuid_SetUID_getgrnam
Now, I am using the shared object that already comes in the jetty download, not the one linked in the wiki.
In addition to that, looking through the code of the setuid module, I decided using the property -Djetty.libsetuid.path in my java args for indicating the absolute path of the lib, e.g., -Djetty.libsetuid.path=/opt/jetty/lib/setuid.so

NullPointerException with LWJGL 3 Initialization

I'm trying to setup a new project in IntelliJ using LWJGL version 3. I just tried out this example: Whenever I try to run it,
I get a java.lang.ExceptionInInitializerError caused by a java.lang.NullPointerException while loading the library.
My natives are in project_root/lib/lwjgl/native/macosx/x64, so my vm argument is:
-Djava.library.path=lib/lwjgl/native/macosx/x64
I have also added lwjgl to the classpath.
The stack trace is:
Exception in thread "main" java.lang.ExceptionInInitializerError
at test.HelloWorld.execute(HelloWorld.java:18)
at test.HelloWorld.main(HelloWorld.java:80)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)
Caused by: java.lang.NullPointerException
at org.lwjgl.LWJGLUtil.loadLibrarySystem(LWJGLUtil.java:326)
at org.lwjgl.Sys$1.run(Sys.java:36)
at java.security.AccessController.doPrivileged(Native Method)
at org.lwjgl.Sys.<clinit>(Sys.java:33)
... 7 more

The solution is to specify an absolute path for java.library.path, rather than a relative one.
On the LWJGL forums, there was a user with a similar problem (I found this by searching for the problematic line and doing some hunting on the forum). The relevant part of the conversation is:
lightbringer writes:
I think I figured it out. In LWJGLUtil.java I took out some code and ran it from my main()`. I got an
java.lang.UnsatisfiedLinkError: Expecting an absolute path of the library: lib/native\lwjgl.dll`
inside loadLibrary(). System.load() apparently needs an absolute path but you are passing it a relative path.
I tested with -Djava.library.path=E:\Dropbox\private\projects\solariad\redist\lib\native and this indeed did work as expected.
The root of the issue is LWJGL's use of System.load(), which is not problematic in itself, but it does requires an absolute path name to the libraries it loads (see source as well).
If you take a look at LWJGLUtil.java (although the version at the time of this writing does not correspond exactly to your stack trace) and Sys.doLoadLibrary(), you can see that it attempts to load libraries by going through all the path strings in java.library.path, appending the library name, and trying System.load() on those paths. Since load() requires an absolute path the implication is that java.library.path must contain the absolute path to the LWJGL libraries as well.
It is unfortunate that the root cause of the problem was muddled by the NPE but, you know, it's a hard knock life for us poor programmers!

java newrelic agent throwing classnotfound exception

I am trying to install newrelic on a linux machine with tomcat 7. This installation does not have a catalina.sh so cannot use the newrelic installer.
I tried the manula approach of adding the newrelic.jar to the javaagent like:
CATALINA_OPTS="$CATALINA_OPTS -javaagent:/usr/share/tomcat7/newrelic/newrelic.jar"
But whenever I start the tomcat I get the following classnotfoundexception:
Unable to start New Relic agent: javax.xml.transform.TransformerFactoryConfigurationError: Provider org.apache.xalan.processor.TransformerFactoryImpl not found
javax.xml.transform.TransformerFactoryConfigurationError: Provider org.apache.xalan.processor.TransformerFactoryImpl not found
at javax.xml.transform.TransformerFactory.newInstance(TransformerFactory.java:106)
at com.newrelic.agent.extension.dom.ExtensionDomParser.getTransformerFactory(ExtensionDomParser.java:360)
at com.newrelic.agent.extension.dom.ExtensionDomParser.fixNamespace(ExtensionDomParser.java:337)
at com.newrelic.agent.extension.dom.ExtensionDomParser.parseDocument(ExtensionDomParser.java:167)
at com.newrelic.agent.extension.dom.ExtensionDomParser.readFile(ExtensionDomParser.java:152)
at com.newrelic.agent.extension.ExtensionParsers$3.parse(ExtensionParsers.java:46)
at com.newrelic.agent.extension.JarExtension.<init>(JarExtension.java:59)
at com.newrelic.agent.extension.JarExtension.<init>(JarExtension.java:104)
at com.newrelic.agent.extension.ExtensionService.initializeBuiltInExtensions(ExtensionService.java:388)
at com.newrelic.agent.extension.ExtensionService.doStart(ExtensionService.java:145)
at com.newrelic.agent.service.AbstractService.start(AbstractService.java:54)
at com.newrelic.agent.service.ServiceManagerImpl.doStart(ServiceManagerImpl.java:124)
at com.newrelic.agent.service.AbstractService.start(AbstractService.java:54)
at com.newrelic.agent.Agent.premain(Agent.java:208)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:622)
at com.newrelic.bootstrap.BootstrapAgent.premain(BootstrapAgent.java:117)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:622)
at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:343)
at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:358)
Caused by: java.lang.ClassNotFoundException: org/apache/xalan/processor/TransformerFactoryImpl
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:270)
at javax.xml.transform.FactoryFinder.getProviderClass(FactoryFinder.java:124)
at javax.xml.transform.FactoryFinder.newInstance(FactoryFinder.java:179)
I have tried everything I could for this, but nothing works. I have even added the xalan jar manually to the tomcat lib but no luck

You need to make sure you have xalan.jar installed. If it is installed, it may be in the wrong place. You probably need it at the container level, here is a blog post that discusses this issue (tomcat5 but most of the advice should still apply).
http://doookstechstuff.blogspot.com/2010/04/how-to-fix-tomcat5-on-rhel5.html

Make sure that the location where you put the xalan.jar is in the classpath and that the user account you're running tomcat under has access to it. If you have dropped it in the tomcat /lib folder make sure the perms for the .jar file match the other objects in the folder.
Let us know if this helps. If you need additional information it might be best to create a ticket with New Relic Support (http://support.newrelic.com).

Why would Java classloading fail on Linux, but succeed on Windows?

I've got a Java web application (using Spring), deployed with Jetty. If I try to run it on a Windows machine everything works as expected, but if I try to run the same code on my Linux machine, it fails like this:
[normal startup output]
11:16:39.657 INFO [main] org.mortbay.jetty.servlet.ServletHandler$Context.log>(ServletHandler.java:1145) >16> Set web app root system property: 'webapp.root' = [/path/to/working/dir]
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.mortbay.start.Main.invokeMain(Main.java:151)
at org.mortbay.start.Main.start(Main.java:476)
at org.mortbay.start.Main.main(Main.java:94)
Caused by: java.lang.ExceptionInInitializerError
at org.springframework.web.util.Log4jWebConfigurer.initLogging(Log4jWebConfigurer.java:129)
at org.springframework.web.util.Log4jConfigListener.contextInitialized(Log4jConfigListener.java:51)
at org.mortbay.jetty.servlet.WebApplicationContext.doStart(WebApplicationContext.java:495)
at org.mortbay.util.Container.start(Container.java:72)
at org.mortbay.http.HttpServer.doStart(HttpServer.java:708)
at org.mortbay.util.Container.start(Container.java:72)
at org.mortbay.jetty.Server.main(Server.java:460)
... 7 more
Caused by: org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: No suitable Log constructor [Ljava.lang.Class;#15311bd for org.apache.commons.logging.impl.Log4JLogger (Caused by java.lang.NoClassDefFoundError: org/apache/log4j/Category) (Caused by org.apache.commons.logging.LogConfigurationException: No suitable Log constructor [Ljava.lang.Class;#15311bd for org.apache.commons.logging.impl.Log4JLogger (Caused by java.lang.NoClassDefFoundError: org/apache/log4j/Category))
at org.apache.commons.logging.impl.LogFactoryImpl.newInstance(LogFactoryImpl.java:543)
at org.apache.commons.logging.impl.LogFactoryImpl.getInstance(LogFactoryImpl.java:235)
at org.apache.commons.logging.impl.LogFactoryImpl.getInstance(LogFactoryImpl.java:209)
at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:351)
at org.springframework.util.SystemPropertyUtils.(SystemPropertyUtils.java:42)
... 14 more
Caused by: org.apache.commons.logging.LogConfigurationException: No suitable Log constructor [Ljava.lang.Class;#15311bd for org.apache.commons.logging.impl.Log4JLogger (Caused by java.lang.NoClassDefFoundError: org/apache/log4j/Category)
at org.apache.commons.logging.impl.LogFactoryImpl.getLogConstructor(LogFactoryImpl.java:413)
at org.apache.commons.logging.impl.LogFactoryImpl.newInstance(LogFactoryImpl.java:529)
... 18 more
Caused by: java.lang.NoClassDefFoundError: org/apache/log4j/Category
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
at java.lang.Class.getConstructor0(Class.java:2699)
at java.lang.Class.getConstructor(Class.java:1657)
at org.apache.commons.logging.impl.LogFactoryImpl.getLogConstructor(LogFactoryImpl.java:410)
... 19 more
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Category
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
... 24 more
[shutdown output]
I've run the app with java -verbose:class, and according to that output, org.apache.log4j.Category is loaded from the log4j JAR in my /WEB-INF/lib, just before the first exception is thrown.
Now, the Java versions on the two machines are slightly different. Both the machines have Sun's java, the Linux machine has 1.6.0_10, while the Windows machine has 1.6.0_08, or maybe 07 or 06, I can't remember the exact number right now, and don't have the machine at hand. But even though the minor versions of the Javas are slightly different, the code shouldn't break like this. Does anyone understand what's wrong here?

You must understand that a classloader can't see everything; they can only see what a parent classloader has loaded or what they have loaded themselves. So if you have two classloaders, say one for Jetty and another for your webapp, your webapp can see log4j (since the JAR is the WEB-INF/lib) but Jetty's classloader can't.
If you manage to make a class available to Jetty (for example something in the DB layer) which uses log4j but which ends up running in the context (and classloader) of Jetty, you will get an error.
To debug this, set a breakpoint in org.springframework.web.util.Log4jWebConfigurer.initLogging(). If you can, copy the source of this class into your project (don't forget to delete it afterwards) and add this line:
ClassLoader cl = Thread.currentThread().getContextClassLoader();
Have a look at the cl object in your debugger. That should give you some information who created it. My guess is that this is the classloader from Jetty.
[EDIT] Note that you get in a different mess if you have log4j in both classloaders: In this case, you will have two classes with the same name which create objects which are not assignment compatible! So make sure there is only a single instance of this jar or that instances of log4j will never be passed between the two contexts (which is usually not possible).

This seems like a classic classloader problem. It could be due to another web app being loaded first which also uses log4j but a version that is different to the one used by the app you are testing. The classloader uses the first version of the class it finds. The server class loading policy can usually be changed in the config files. Sorry I am a bit rusty on this but maybe it can point you in the correct direction.
Make sure there are no other installed apps on the web server,
Make sure the log4j being loaded is the correct version,
Make sure you don't have a log4j lurking somewhere in the classpath of the server.
HTH

You're using the same WAR on both machines? Have you checked if the WAR files are identical (no transfer errors occured)?

Some random things to consider:
(1) Check if there are any other versions of log4j floating around on the linux instance, outside of the web-app directories?
(2) Is apache commons logging being used at all? You might want to consider SLF4J instead?
(3) Did the JAR/WAR become corrupt in some way - was it FTP'ed in ASCII or Binary?
(4) Print out the classloader hierarchy in each case, just to see if there are any discrepancies?

Even though the original problem was solved for the asker, I'll point out that a common source of problems when running the same code on Windows vs Linux (or Unix) is case-sensitivity issues. Windows ignores case while Linux or Unix is case-sensitive. This has bitten me more than once.
So if you specify a jar or directory on the classpath, but it isn't the right case then it will fail on Linux but succeed on Windows. This can also be the source of FileNotFoundExceptions.

Had the same problem and found an easy solution/workaround:
In Eclipse in Preferences > Java > Installed JREs, select the JRE > Edit and Add External JARs... and browse to your log4j.jar.
The other workaround is to add log4j.jar to every launch definition in Classpath tab.