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Server App Engine Standard at localhost failed to start

From eclipse, I created a Google App Engine Standard project and tried to Run it on local App Engine. It is not starting and throwing the below errors -
java.lang.NullPointerException
at java.base/java.util.concurrent.ConcurrentHashMap.putVal(ConcurrentHashMap.java:1011)
at java.base/java.util.concurrent.ConcurrentHashMap.put(ConcurrentHashMap.java:1006)
at java.base/java.util.Properties.put(Properties.java:1316)
at java.base/java.util.Collections$CheckedMap.put(Collections.java:3636)
at com.google.appengine.tools.development.SharedMain.setTimeZone(SharedMain.java:219)
at com.google.appengine.tools.development.SharedMain.postServerActions(SharedMain.java:188)
at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:398)
at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:45)
at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:257)
at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:248)
Also note that I haven't made any changes to the project. It's the default that gets created.

This is likely an issue with your jdk version. What does javac -version report back? I run into the same stack trace with version 12. Switching to 1.8 works.
On MacOS, this answer helps: How to set or change the default Java (JDK) version on OS X?
Other platforms should have similar ways to switch versions.

This looks to be a JDK12 issue - it seems JDK12 is restricting the system properties exposed to programs, I've run into a similar issue with the OS version before.
I've reported it to Google, you can star it so they feel the weight of the matter: https://issuetracker.google.com/issues/140787205

Does Japser Reports work with Java9

Im having trouble using Japser Reports with Java 9.
My JasperVersions:
<dependency.version.jasper>6.5.1</dependency.version.jasper>
When trying to build my Report i get the following error Message:
An internal error occurred during: "Building report".
java.lang.UnsupportedClassVersionError: my/path/to/my/class/User has been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0
the Error occurrs probbably because Jasper does not Support java 9 Classes. I cant find any information on this topic, does anyone have a Idea how to write a workaround or did i do some other mistake?
EDIT:
After searching some more i realised that the problem only happens when im in the Designer in Eclipse, so it is most likely that eclipse itselve is not running in a JVM 9. I checked for the current version of java installed and it is java9, when i change the eclipse.ini file from:
-Dosgi.requiredJavaVersion=1.8
to
-Dosgi.requiredJavaVersion=1.9
i get a incompatible jvm error which says that im trying to start it with 1.8.0_161. How do i change my settings that my eclipse is acutally using my current JDK?
RESOLVED:
The error was that my Eclipse itselve only run in Java8. So my Application was building everything in Java9, like i wanted it to, but when i was inside the jasperReports Designer, the designer itselve run in java8. Thats why it crashed. The solution was to change the systemvariables and put my JavaPath over the Oracle JavaPath that for some reason had a higher priority.

Code was compiled in Java version 9 but executed in Java 8 JVM, which not necessarily works. Try compiling it in Java 8, or executing it in Java 9 JVM.

MessageDispatcher is NULL when it is migrated from web logic server to tomcat server

I am migrating my spring soap based application from web logic 10.3.5 server to tomcat 7 server. When used the existing war file from weblogic in to tomcat, i got more no of exceptions. I think tomcat is not loading the files. I got around 1440 aspectJ core files in tomcat. some of the exceptions are like
class org.springframework.ws.server.MessageDispatcher
class org.springframework.xml.xpath.Jaxp13XPathExpressionFactory$Jaxp13XPathExpression
class org.springframework.xml.namespace.SimpleNamespaceContext to -- (NullPointerException) null
null
java.lang.NullPointerException
I just conveyed it short. if it is not clear please let me know.

I found solution for my issue. When i checked my javac and java version's both are miss matching. javac -version is 1.6 and java -version is 1.8. Also my application is built on java 1.6 where as tomcat(7.0.42) java jvm version displayed as 1.8. I have changed tomcat java jvm version to 1.6. now all my exceptions related to application run are gone.
i have look into project specific errors to resolve.
Thank you for your time.

Compiling against Java 7 in JDeveloper 10

Is it possible to use Java 7 in JDeveloper 10?
I have an application that works correctly in Java 5. I've updated the java.conf file to point to the Java 7 jdk, and I've changed the project properties to use the same Java 7 J2SE. When I try to compile, however, I get many errors similar to those below:
Error: class format error: Object.class on classpath C:\Program Files (x86)\Java\jdk1.7.0_40\jre\lib\rt.jar/java/lang/Object.class
Error: Object not found
Error: class format error: Class.class on classpath C:\Program Files (x86)\Java\jdk1.7.0_40\jre\lib\rt.jar/java/lang/Class.class
Error: Class not found
Error: class format error: String.class on classpath C:\Program Files (x86)\Java\jdk1.7.0_40\jre\lib\rt.jar/java/lang/String.class
Error: String not found
It seems to be choking on the java definitions themselves. I'm hoping I'm just missing a step somewhere.
Also, upgrading to a later version of JDeveloper is not an option. JDeveloper 12, as far as I've been able to tell, will not deploy to an OC4J instance.

No, you can not use jdk 1.7 together with jdev 10g. You have to stay with Java 5.
And yes, you can't upgrade to 11g or 12c as they don't use oc4j but Web logic Server.

one more notice from me. jdeveloper 10 does not run itself (this means jdeveloper 10g software does not start) with java 64 bit. also not with java6. However, if you successfully started jdeveloper with java 32 bit, you can use java 6 (jdk6) to compile and run your java applications. This can be done by changing the property of your project. Just add there a new java machine 64 bit (under libraries) and let the project us it.

How to use the Play Framework with Google App Engine with locally installed Java 7?

I've just downloaded the latest version of the Play Framework (1.2.3) and am using it with the latest Scala plugin (0.9.1) and the Google App Engine module (1.4).
The default application works fine locally (at localhost:9000, the default port). I've also successfully published the default application to GAE using play gae:deploy.
However, when I go to the GAE remote URL, I get the standard error message:
Error: Server Error.
The server encountered an error and could not complete your request.
If the problem persists, please report your problem and mention this error message and the query that caused it.
Here is the full stacktrace in the GAE logs: https://gist.github.com/1181257
I'm guessing the first error, the NPE, is due to something that can be easily fixed, so ignore that for now; however, note the second - critical - error, which says:
java.lang.UnsupportedClassVersionError: helpers/CheatSheetHelper$1 : Unsupported major.minor version 51.0
51.0 is (I think) the class version that the Java 7 compiler generates. Now, my question is simple:
How to force the Play Framework and its Scala plugin to compile the classes for GAE publishing using the -target 1.6 and -source 1.6 options, so that the output classes are 1.6 compatible, instead of the defaults, which make the local Java 7 installation generate 1.7 output classes?
Thanks.
[edit] As for the NPE, it seems that it's not thrown on Play 1.2.1 and the 0.9 version of the Scala plugin: Play framework with scala and GAE - again, this is just a side issue, the primary issue (getting Java 7 working) still stands. I've created a ticket for this: http://play.lighthouseapp.com/projects/74274-play-scala/tickets/45-nullpointerexception-on-google-app-engine

To get java 7 to work currently, you have to use the following configuration in your application.confirm file
java.source=1.6
See here for more details - VerifyError; Expecting a stack map frame in method controllers.Secure$Security.authentify

Java 7 is fully supported for Play 1.2.4 RC3 - give it a try and see if it solves your issues.

I just ran into the same issue. I'm running Java 7 and don't want to have all my other Java stuff run on 6 again. So, what I did was dump a copy of JDK 6 in a directory and then made a simple bash script to set the proper environment vars and call play. I then symlinked that script as "play" on my path. Now when play gets called it has a JDK 6 environment to run under without having to change everything else on the machine.
...less than ideal, but it works well enough and keeps everything clean.