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Run a batch file in Python which contains java command

It is quite frustrating when you can't execute a .bat file in python while it is executing manually.
I am attaching my code here:
directory = 'E:/'
with open(os.path.join(directory, 'output_file.bat'), 'w') as OPATH:
OPATH.writelines(['"""',"\n"'E:',"\n",
'javacCreatingUser.java',"\n",'javaCreatingUser',"\n",'"""'])
os.system("E:/output_file.bat")
The above is my python code which is creating a bat file with 2 java command
javac CreatingUser.java
java CreatingUser
I can run the .bat file manually and it is working fine but my python script is giving me the following error:
java.lang.NoClassDefFoundError: oracle/iam/identity/exception/ValidationFailedException
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.privateGetMethodRecursive(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: oracle.iam.identity.exception.ValidationFailedException
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)
... 7 more
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" '"""' is not recognized as an internal or external command,
operable program or batch file.
The question is that if some classes are missing in my file then it should not execute manually as well, but manual execution is fine.

javac CreatingUser.java
java CreatingUser
This is the source of your problem: You're only compiling one class file and then calling that class without a classpath.
Java has a search path for classes comparable to Pythons PYTHONPATH called classpath.
You can give this a try:
javac CreatingUser.java
java -classpath YOUR_CLASSPATH CreatingUser
YOUR_CLASSPATH can be a colon (Linux) or semicolon (Windows) separated list of JAR files and directories containing class files. Let your classpath point to the JARs you're needing and you're fine.

Java Web Start not working after updating Java 8u141 - java.lang.SecurityException: digest missing for org/apache/commons/httpclient

After updating Java 8u141, my java web start application, run by jnlp stopped working. Do not download the application. And throws these exceptions below. Can someone help me?
com.sun.deploy.net.JARSigningException: Could not verify resource signature: http://www.example.com/myjar.jar
at com.sun.deploy.security.JarVerifier.authenticateJarEntry(Unknown Source)
at com.sun.deploy.security.EnhancedJarVerifier.validate(Unknown Source)
at com.sun.deploy.cache.CacheEntry.processJar(Unknown Source)
at com.sun.deploy.cache.CacheEntry.access$2700(Unknown Source)
at com.sun.deploy.cache.CacheEntry$7.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.cache.CacheEntry.writeFileToDisk(Unknown Source)
at com.sun.deploy.cache.CacheEntry.writeFileToDisk(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToTempFile(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToCache(Unknown Source)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.javaws.LaunchDownload$DownloadTask.call(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Other:
java.lang.SecurityException: digest missing for org/apache/commons/httpclient
at sun.security.util.ManifestEntryVerifier.verify(Unknown Source)
at java.util.jar.JarVerifier.processEntry(Unknown Source)
at java.util.jar.JarVerifier.update(Unknown Source)
at java.util.jar.JarVerifier$VerifierStream.<init>(Unknown Source)
at java.util.jar.JarFile.getInputStream(Unknown Source)
at com.sun.deploy.security.JarVerifier.authenticateJarEntry(Unknown Source)
at com.sun.deploy.security.EnhancedJarVerifier.validate(Unknown Source)
at com.sun.deploy.cache.CacheEntry.processJar(Unknown Source)
at com.sun.deploy.cache.CacheEntry.access$2700(Unknown Source)
at com.sun.deploy.cache.CacheEntry$7.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.cache.CacheEntry.writeFileToDisk(Unknown Source)
at com.sun.deploy.cache.CacheEntry.writeFileToDisk(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToTempFile(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToCache(Unknown Source)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.javaws.LaunchDownload$DownloadTask.call(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

I managed to solve this same issue yesterday. This is what worked for me:
Use 7-Zip to open the original, unsigned jar which is throwing the JARSigningException. Probably a good idea to make a copy of the jar first in case anything goes wrong.
Open the META-INF folder and copy MANIFEST.MF somewhere to your PC.
Open the MANIFEST.MF copy in a text editor. Look for a line that says something like "Name: org/apache/commons/httpclient". There could be a few lines like this, depending on the jar. Below this line will probably be other lines like "Implementation-Vendor:...", "Specification-Title:...", etc. In any case, delete all "Name:..." lines and all the subsequent lines in each block.
Save the file, and replace the existing MANIFEST.MF in the jar with the edited version. 7-Zip allows files to be replaced inside jars in-situ.
Re-sign the jar and deploy.
It seems when jars get signed, the "Name:" lines in the manifest can wind up in the middle of the signed classes, which only now seems to be a problem with the release of Java 8u141 but were obviously fine before.

The issue is already fixed in 8u144, please upgrade to 8u144 to avoid this issue http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

I had the same problem with the commons-httpclient-3.1.jar library. Actually I believe it's a bug in the web start, as It worked before and it works with the 8u152 early access. The solution I described here!

The issue is observed in signed JAR files whose manifest contains package version information[1] and does not have a trailing "/" in the name of the package (e.g.: Name: org/apache/xml/resolver). While we work towards resolving this issue, in the interim, users can work-around the issue as follows:
NOTE: We recommend use of this workaround only if the distributor of the JAR files can "re-sign" the JAR files.
Extract the contents of the signed JAR file (e.g.: jar xf jar-file ).
Modify META-INF/MANIFEST.MF file and add a trailing “/” to the name of the package ( e.g.: Name: org/apache/xml/resolver/).
Remove the current signature files ( e.g.: rm -f META-INF/.SF META-INF/.RSA META-INF/*.DSA ).
Recreate the JAR file ( e,g.: jar cfm jar-file META-INF/MANIFEST.MF input-file(s) ).
NOTE: You must use the jar utility. Other jar creation tools might re-introduce the issue.
Re-sign the JAR file.
[1] https://docs.oracle.com/javase/8/docs/technotes/guides/versioning/spec/versioning2.html#wp91706
Source:
http://www.oracle.com/technetwork/java/javase/8u141-relnotes-3720385.html#KnownIssues

This bug is addressed as part of the bug JDK-8184993 and the fix will be available in an out-of-cycle release of JDK 8u144, which is scheduled to be released on later hours of July 26.

Running java file in cmd - error given

I recently moved a project from one machine to another but I am now given an error when attempting to run java files on the new machine. I'm trying to run a java file from part of an Android project in command prompt but I am given an error. The file compiles okay but fails to run. Here is the error I am given;
Exception in thread "main" java.lang.NoClassDefFoundError: ChatServer (
e: edu/UTEP/android/ChatServer)
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$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Any ideas why I am receiving this error?

Your ChatServer is having a package declaration of edu.UTEP.android in the top. So either you need to remove that package declaration recompile your java file again and run it
(or)
you need to create folder structure like this
CurrentDir/edu/UTEP/android/
Keep your java file in android folder and invoke java ChatServer from CurrentDir. Any of these two will solve the issue :-)
For more info on packages, you can refer to my previous answer on a similar issue here

Make sure that the .jar that provides ChatServer is in your runtime Classpath.

This issue rise when jvm don't file class path.
check where u have placed your jar file or lib folder.
Move to that directory then run javac and then java .
Issue will be resolved.

Why do I get "A Java Exception has occurred" after I export my application to Jar?

Well, I exported my application into JAR with eclipse, but now whenever I try running it I get the: "A Java Exception has occurred". When I try to run it through command line it says:
C:\Users\Arturas>java -jar D:\Dropbox\EclipseWorkspace\Exports\Dantracio_skaiciu
oklis3.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/eclipse/swt/widge
ts/Composite
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.getMainMethod(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.eclipse.swt.widgets.Composite
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
C:\Users\Arturas>
Any solutions to this? I just hate java for this... It never works on desktops when you want it to... sorry I'm really stressed out from this, I'm overreacting...
Any ideas what could cause this? I doesn't work on other computers as well. Right now it's using Java 1.7. And the application runs perfectly on Eclipse.

You need to get your dependencies. Looks like you are depending on swt, which is not part of the core java language. You'll need to get all the third party jars that you depend on and include them in your classpath. It runs perfectly on eclipse because eclipse takes care of setting up the classpath for you.
You can set the classpath in your manifest file as described in the documentation, or you could include a script to start your application that will use the -cp command when running the jar, or you can use something that will package everything into one monster jar like the solutions to this question.

Why am I getting an exception when running a JAR file from the command prompt?

Hi I have made a runnable JAR file useing export option on eclipse. However, when I go to run the file via command prompt i get the following
Exception in thread "main" java.lang.NoSuchMethodError
at org.eclipse.jdt.internal.jarinjarloader.RsrcURLConnection.getInputStream(RsrcURLConnection.java:43)
at java.net.URL.openStream(Unknown Source)
at sun.misc.URLClassPath$Loader.getResource(Unknown Source)
at sun.misc.URLClassPath.getResource(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.ClassLoader.loadClassInternal(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)
Does any one have any ideas as to what im doing wrong? pretty new to the whole creating runnable files etc.

Your jar is compiled with a newer version of java than the computer you are running it on.

Extract the jar file look for the file META-INF/MANIFEST-MF. This file should have an entry
Main-Class : <you fully qualified classname having main method>
Check if the class you mentioned as Main-Class has a main method (public static void main(String[] arg))