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JasperReport cannot find symbol JREvaluator in WildFly, works without server

Recently I've been working on report generation with Jasper. I have created a simple program to test it and when running it via IDE it did work fine.
Then I moved the (very short) class to WildFly sever application and despite having the exact same code and library generation fails with cannot find symbol. Those symbols it cannot find are JREvaluator, JRFillVariable as well as packages such as net.sf.jasperreports.engine
In so far I have confirmed that:
Project builds (meaning those classes are visible for javac, but not jvm)
jasperreports-6.13.0.jar is added to war (it's present in /WEB-INF/lib folder alongside other libraries, like gson and hibernate
jasperreports-6.13.0.jar contains the missing classes
It looks to me like the problem doesn't lie in library not being loaded or missing classes (because in testing environment it works), but like something was preventing JBoss class loader from loading those classes
Attempted (and failed) solutions
Clean and Build
Adding -Djava.awt.headless=true to VM options - this did not changed anything
Adding -Djava.awt.headless=false to VM options - also didn't change a thing, but once caused NullPointerException inside jasperreport library. For testing program - worked in both cases
Adding commons-beanutils-1.9.4.jar, commons-digester-2.1.jar, commons-collections4-4.4.jar and commons-loggin-1.2.jar - with no changes
Adding jasper-compiler-jdt-5.5.23.jar - this caused a different error, namely NoSuchMethodError for org.eclipse.jdt.internal.compiler.ICompilerRequestor and few others. This library however should not be necessary as - from what I understand - jasperreport-6.13.0.jar already contains it's compiler and separate library for compiler is not required since a long time.
What has not been attempted:
Forcing the classes to load (http://www.java2s.com/Code/Java/Reflection/Forcethegivenclasstobeloadedfully.htm)
Dynamically loading jar during Runtime or using custom class loader
Update: after looking at this answer and applying the suggestion the missing class was different. Which suggests that the dependencies inside jasperreport.jar are not being loaded properly

I have figured it out
For some reason in server project libraries used by jasperreport.jar were not loaded, but in the testing project they were (might be due to WildFly, might be due to differences between IntelliJ and NetBeans)
Here is the list of libraries, based on pom.xml file in jasperreport.jar that I have added. Some might not be necessary and the list might not be exhaustive (I basically stopped adding libraries once report started generating) but it's good enough base if someone else runs into this problem:
commons-beanutils-1.9.4.jar
itext-2.1.7.jar
poi-ooxml-4.1.1.jar
commons-collections4-4.4.jar
jcommon-1.0.23.jar
xalan-2.7.2.jar
commons-digester-2.1.jar
jfreechart-1.0.19.jar
xmpcore-5.1.3.jar
commons-logging-1.2.jar
poi-4.1.1.jar

Build OpenCV with contrib modules and Java wrapper

I'm trying to build OpenCV on my Windows 7 machine. To include the contrib modules I have added the OPENCV_EXTRA_MODULES_PATH in CMake-gui. The opencv-300.jar and opencv-300.dll have been created but I can not find the Java classes to use the extra modules. Am I missing an option in the make configuration? Is it possible to use these extra modules from Java?

i've the same problem and i resolved in this way. I imagine that you had downloaded from contrib repo the specific version match with the opencv version if you want to build. So go in directory and enter, for example, face module directory; in this directory there is a file called CMakeLists.txt that you have to edit. This file should be like this:
set(the_description "Face recognition etc")
ocv_define_module(face opencv_core opencv_imgproc opencv_objdetect WRAP python)
# NOTE: objdetect module is needed for one of the samples
If you want to have the org.opencv.face package in your opencv-3xx.jar library you have to modify the 2nd line of the file in this way:
ocv_define_module(face opencv_core opencv_imgproc opencv_objdetect WRAP python java)
Then you have to compile opencv as depicted in the Readme.md of the contrib repo https://github.com/itseez/opencv_contrib
Obviously the same thing is valid for all the contrib modules if you want to add to your opencv-3xx.jar library.
I hope that this solution works for you, bye!

How do you get gradle to access a string from a Java class in the project in my build.gradle?

I'm fairly new to Gradle so excuse my ignorance: I have a class that has a static string containing the build version I want to set for the project. With gradle, I can't seem to access the project directly with just MyClass.MyVersionString.
What would be the easiest way to go about it? I can't seem to find a simple way of doing this.
Alternatively, if there was a way to access the Gradle version from my project, that too would help. The project needs access to the version, so I'd like a way to set it in one place and have everything else automagically update.
Thanks!

If building an Android project, you can do it the other way: use BuildConfig.VERSION_NAME (or BuildConfig.VERSION_CODE), depending on what you need.
The BuildConfig class is automatically generated from the information in the AndroidManifest (and some other places, such as the flavor you're building).

How do you create a jar file of classes that can be re-used by multiple Android projects?

Here are the steps I have followed so far, with no luck. I am extremely new to Java projects so I suspect I may be missing something obvious.
Using Eclipse, I have created a simple Java project called TestSDK, created within that a package called com.test.testsdk, and within that the following class:
package com.test.testsdk;
public class TestClass {
public void TestMethod() {
}
}
This compiles without errors or warnings.
I then export this as a JAR file (TestSDK.jar) using Eclipse and the standard export options (export generated class files and resources, compress the contents of the JAR, generate manifest file). I have tried both sealing and not sealing the JAR which makes no difference.
I then create a new Android application project from File->New->Project in the Wizards list. This compiles and runs without warnings or errors on both the Android emulator and my test device (I get the hello world message).
I then add a reference to my TestSDK.jar file (using a variety of different methods as I will expand on shortly), import it into the main (and only) Android activity, and try to instantiate my TestClass and call TestMethod on it, like so:
package com.apptest.mobilesdktestapp;
import android.app.Activity;
import android.os.Bundle;
import com.test.testsdk.TestClass;
public class MobileSDKTestAppActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TestClass test = new TestClass();
test.TestMethod();
}
}
This compiles fine without warnings or errors. When trying to run it on the emulator or the device, however, I get the following error in my LogCat window:
AndroidRuntime Uncaught handler: thread main exiting due to uncaught exception
AndroidRuntime java.lang.NoClassDefFoundError: com.test.testsdk.TestClass
Searching the web for the NoClassDefFoundError results in a lot of suggestions on how to import the JAR file such that the class path is correct. As a result, I have tried all of the following methods of importing the JAR file:
"Add External JARs..." from the Libraries tab of Java Build Path in the project properties, followed by checking (or not checking, I tried both) the JAR in the Order and Export tab. Also tried moving the JAR to the top of the Order and Export list, which made no difference.
Creating a "libs" folder in the project, and adding the JAR there. I confirmed that the JAR is then also added to the "Android Dependencies" thing in the project list. Also tried right-clicking the JAR file and selecting Build Path->Add to Build Path which made no difference.
Moving the JAR into my Android Application project directory and doing "Add JARs..." instead of external JARs as in step 1, also all permutations of exporting or not and moving it to the top of the order list or not.
I have subsequently downloaded other 3rd party SDKs that are packaged as JAR files and included those in the very same Android application project, and those have all worked fine using any of the 3 methods above (I am able to instantiate classes from those SDKs and use them without error), which leads me to believe I am missing something or doing something wrong in my TestSDK project and/or class which is preventing it from being used in the Android Application project.
As I said, I am very new to Java, so I'm hoping it's something simple that I've overlooked. Any help or guidance would be appreciated.

If you are on R17 or higher version of the Android tools and ADT in Eclipse, then the first sentence of #2 is the correct answer; everything else listed in your question is unnecessary at best or harmful at worst.
I would recommend that you create a clean project, create the test activity, create the libs/ folder, copy the JAR into the libs/ folder, code to the JAR's API, compile, and run. If that works, then your original project still has stuff lingering around from your previous efforts that is causing you grief. If it fails, then something fairly strange is going on. The JAR itself is presumably fine, otherwise you would get compile errors.

I think I figured out what the issue was (or at least how to fix the issue, I'm still not 100% sure what I did)--
When I created the original TestSDK java project, I let it target the default JRE in the project creation dialog (jre7).
Checking the project properties of a new Android Application project, the Java Compiler section has "Compiler compliance level" set to 1.5. So, I tried recreating my TestSDK project again, but told it to use J2SE-1.5 as the execution environment instead of the defalut jre7.
After doing this, exporting the JAR and importing it to the Android project's libs directory, I am now able to instantiate the TestSDK classes and use them just fine without the NoClassDefFoundError exception.
Best guess is that the Android application was being compiled against an older version of the JRE than my TestSDK class (which I believe was targeting JavaSE-1.7), causing the issues. Matching the two versions up has solved it.

Using MessagePack with Android

Has someone tried to use MessagePack with an Android app?
Is it possible? I have tried to use the Jar from msgpack-java and received the following Exception:
Caused by: java.lang.ExceptionInInitializerError
at org.msgpack.Packer.pack(Packer.java:532)
at org.msgpack.MessagePack.pack(MessagePack.java:31)
... 15 more
Caused by: java.lang.ExceptionInInitializerError
at org.msgpack.template.TemplateRegistry.<clinit>(TemplateRegistry.java:38)
... 17 more
Caused by: java.lang.VerifyError: org.msgpack.template.BeansFieldEntryReader
at org.msgpack.template.builder.BeansTemplateBuilder.<init (BeansTemplateBuilder.java:42)
at org.msgpack.template.builder.BuilderSelectorRegistry.initForJava(BuilderSelectorRegistry.java:73)
at org.msgpack.template.builder.BuilderSelectorRegistry.<clinit>(BuilderSelectorRegistry.java:38)
... 18 more
The code that I use is very simple
PrintWriter out = new PrintWriter(socket.getOutputStream());
Message msg = new Message();
msg.body = "asdasdasd";
msg.from = "qwe";
msg.to = "ttt";
byte[] bytes = MessagePack.pack(msg);
out.print(bytes);
out.flush();
I have javassist.jar, msgpack-0.5.2.jar, slf4j-api-1.6.2.jar and slf4j-jdk14-1.6.2.jar in my lib directory.
In my server application this code works fine with the same libraries.

(Hopefully) FINAL UPDATE
msgpack : 0.6.8 works on Android without any problems
msgpack-rpc : 0.7.0 works on Android with one caveat.
Specifically, you need to add the following to onCreate for API Level 8 (Android 2.2.1), and possibly lower:
java.lang.System.setProperty("java.net.preferIPv4Stack", "true");
java.lang.System.setProperty("java.net.preferIPv6Addresses", "false");
due to this bug.
If you want to see a simple example, here's a pair of projects set up for this purpose:
https://github.com/mikkoz/msgpack-android-test-server/tree/master/msgpack-android-test-server
https://github.com/mikkoz/msgpack-android-test-client/tree/master/msgpack-android-test-client
Previous Versions
UPDATE: as of 0.6.7 msgpack should be compatible with Android (there is a small dependency exclusion issue). Check the text below for msgpack-rpc (which also might be adapted in the future).
NOTE: If you're also using msgpack-rpc, you need to do the following steps:
Download the msgpack-rpc source from git://github.com/msgpack/msgpack-rpc.git (specifically, the "java" folder).
Change the main msgpack artifact version to the one you've built.
In org.msgpack.rpc.loop.netty.NettyEventLoop, change the NioClientSocketChannelFactory to OioClientSocketChannelFactory(getWorkerExecutor()).
Build the MessagePack-RPC in the same way as in the case of the main MessagePack JAR (see Step 11 above).
The NettyEventLoop replacement is due to this issue:
http://markmail.org/message/ypa3nrr64kzsyfsa .
Important: I've only tested synchronous communication. Asynchronous might not work.
And here's the reason for msgpack not working with Android prior to 0.6.7:
The reason for the error is that MessagePack uses several java.beans classes that are not included in the Android SDK. You're probably using the MessagePackBeans annotation.
This is a similar problem to the one described here, for which the general solution is outlined here. Unfortunately, in our case it requires a rebuild of msgpack. Here's what I did (you can almost certainly skip Steps 5 and 8, but I haven't tried it that way) :
Download the MessagePack source from https://github.com/msgpack/msgpack-java.git.
Import the MessagePack source as a project in your IDE.
Download the Apache Harmony source for the relevant packages from http://svn.apache.org/repos/asf/harmony/enhanced/java/trunk/classlib/modules/beans/src/main/java .
Copy these packages into your MessagePack project's src/main/java folder:
java.beans
java.beans.beancontext
org.apache.harmony.beans
org.apache.harmony.beans.internal.nls
In your MessagePack project, remove the following classes:
PropertyChangeListener
IndexedPropertyChangeEvent
PropertyChangeEvent
PropertyChangeListenerProxy
PropertyChangeSupport
Rename the java.beans packages to something different, e.g. custom.beans .
Change all java.beans references to the renamed ID, so again e.g. custom.beans. This applies especially to BeansFieldEntryReader (this class is the reason for the original error).
Change the custom.beans references for the five classes you removed in Step 5 back to java.beans.
In the org.apache.harmony.beans.internal.nls.Messages class, comment out the method setLocale, and remove the imports associated with it.
Remove all classes that still have errors, except Encoder. In that class, comment out all references to the classes you've removed. You should now have an error-free project.
Build the MessagePack JAR:
If you're using Maven, change the version in the pom.xml to something unique, run Maven build with the install goal, then add the dependency in your Android project with that version.
If you're not using Maven, you have to run the jar goal for Ant with the included build.xml. Replace the msgpack JAR in your Android project with this one.
If you're publishing your app, remember to include the relevant legal notice for Apache Harmony. It's an Apache License, just like MessagePack.
That should do it. Using your example code, and my own data class, I was successfully able to pack and unpack data.
The entire renaming ritual is due to the fact that the DEX compiler complains about java.* package naming.

There is a critical msgpack bug saying data packed with msgpack will get corrupted on the Dalvik VM. http://jira.msgpack.org/browse/MSGPACK-51

There is an ongoing effort by #TheTerribleSwiftTomato and the MessagePack core team to get MessagePack working on Android, please see the related GitHub issue. The fix mentioned in #TheTerribleSwiftTomato's answer is to be found here.
Update
I've managed to get it at least running on Android by (painstakingly) adding all the necessary javassist Classes which are currently required for the build to succeed. An extra 600KB gain in size, yet at least it seems to work. All in all, it appears to be working to some extent on Android, eventually check out the lesser-known resources about Message Pack such as its User Group and its Wiki for more information.
On a side-note, be sure to use a HTTP Request Library (such as LoopJ's Android Async HTTP or Apache's HttpClient) which can handle binary data.
Last but not least you can ping me if there is interest in this jar which makes MessagePack seemingly work on Android – credits go out of course to #TheTerribleSwiftTomato who supplied the fix above!

I suggest you write this in the main proguard-rules file-
-dontwarn org.msgpack.**
-keep class org.msgpack.** { *; }