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Missing class from package within Netbeans when using Spire.Doc.jar for docx files

I downloaded and installed the free Spire.Doc.jar file to work with .docx files. When I run it within Netbeans the functionality works fine however when I attempt to build the program I am getting the following error:
warning: Supported source version 'RELEASE_6' from annotation processor 'org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProcessor' less than -source '1.8'
Note: Creating static metadata factory ...
error: com.sun.tools.javac.code.Symbol$CompletionFailure: class file for com.spire.doc.packages.spryOb$1
not found
An annotation processor threw an uncaught exception.
Consult the following stack trace for details.
java.lang.RuntimeException: com.sun.tools.javac.code.Symbol$CompletionFailure: class file for com.spire.doc.packages.spryOb$1 not found
I have added the .jar file to my class path however there appears to be a class file missing from the com.spire.packages location.
Does anyone know if this is a Netbeans issue or does it look like there is an issue with the .jar file? I find it strange that it works when I run it within Netbeans but the above error occurs when I attempt to build the project.

I managed to get my application to build. What I had to do was remove the following code from my class and then it worked:
document.getMailMerge().MergeImageField = new MergeImageFieldEventHandler()
{
#Override
public void invoke(Object sender, MergeImageFieldEventArgs args)
{
mailMerge_MergeImageField(sender, args);
}
};
private static void mailMerge_MergeImageField(Object sender, MergeImageFieldEventArgs field)
{
String filePath = field.getImageFileName();
if (filePath != null && !"".equals(filePath))
{
try
{
field.setImage(filePath);
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
I'm not sure why it didn't work with this included however I got this code from the following website:
https://www.c-sharpcorner.com/article/how-to-perform-mail-merge-in-word-document-in-java/
therefore I will inform them in case this happens to someone else in the future.

Missing resolveStrategy breaks DSL when executed from runnable jar

I'm using the Groovy Spreadsheet Builder within one of my Grails projects to export some data as Excel file.
Everything works great until I create a runnable jar (using gradle assemble) and use this.
I'm using the builder within a service like this:
class ExcelService {
...
void export(OutputStream outputStream) {
...
PoiSpreadsheetBuilder.create(outputStream).build {
apply ExcelStylesheet
...
}
}
...
}
When I try to export my data from the app started using the generated jar I will get the following MissingMethodException:
groovy.lang.MissingMethodException: No signature of method: my.package.ExcelService.apply() is applicable for argument types: (java.lang.Class)
The (Java) interface of SpreadsheetBuilder looks like this:
public interface SpreadsheetBuilder {
void build(#DelegatesTo(strategy = Closure.DELEGATE_FIRST, value = WorkbookDefinition.class) #ClosureParams(value = FromString.class, options = "builders.dsl.spreadsheet.builder.api.WorkbookDefinition") Configurer<WorkbookDefinition> workbookDefinition);
}
While debugging the execution of the code and the jar I found the difference while stepping through invokeMethod() of ClosureMetaClass.
When closure.getResolveStrategy(); in the working version is called Closure.DELEGATE_FIRST will be returned. Debugging the jar, the result will be 0 so that the MissingMethodException will be thrown later due to the wrong resolve strategy.
For now I have no idea how to solve this problem.
What is/could be the reason for this behavior?
What can I do to solve this issue?
I'm using Grails 3.3.8 with Java OpenJDK 1.8.0_192.

If you don't need to support JDK 7, you could upgrade to Groovy Spreadsheet Builder 2.0.0.RC1 which is only JDK 8 compatible but appears to solve the problem.

#ClosureParams and #DelegatesTo are applicable to parameters of type groovy.lang.Closure. In this case, you have applied it to Configurer<WorkbookDefinition>.

Intelij scala project does not support swing

I am unable to use swing library with my scala-sdk-2.12.4.
I am using Java 9 version.
When I try to run the program:
package rs.ac.bg.etf.zd173013m.gui
import swing._
object HelloWorld extends SimpleSwingApplication {
def top = new MainFrame {
title = "First Swing App"
contents = new Button {
text = "Click me"
}
}
}
I get the following error:
Exception in thread "main" java.lang.IncompatibleClassChangeError: Method scala.swing.Reactor.$init$()V must be InterfaceMethodref constant
at scala.swing.SwingApplication.<init>(SwingApplication.scala:4)
at scala.swing.SimpleSwingApplication.<init>(SimpleSwingApplication.scala:13)
at rs.ac.bg.etf.zd173013m.gui.HelloWorld$.<init>(Application.scala:5)
at rs.ac.bg.etf.zd173013m.gui.HelloWorld$.<clinit>(Application.scala)
at rs.ac.bg.etf.zd173013m.gui.HelloWorld.main(Application.scala)

You have incompatible JAR versions on your classpath. The code in the JAR containing "SwingApplication" was compiled against a different version of "Reactor" than the one on your classpath.
What are you using to manage your dependencies? I guess that you are downloading them manually.
Switch to a dependency management system like Gradle and this problem should go away, as it will ensure that all your dependencies are consistent.

Getting an UnsatisfiedLinkError (undefined symbol) in Java while loading JNI dependencies even after successfully loading the required object file

I'm using Google OR-tools library (v6.4) for a project (though my question is not specific to this library). This consists of one jar, which has a few native dependencies (a bunch of ".so"/".dylib" object files, depending on the OS). This build for my project is being made on Ubuntu 14.04
The problem I'm facing: On trying to load a specific object file at runtime (using System.load()), I'm getting an UnsatisfiedLinkError with the message as "undefined symbol" (I've added the stacktrace below). However, I am loading the object file defining this symbol just before this, so I'm not sure why this error is being thrown.
I'm loading the dependencies in the following way: The object files are being packed into the jar created by Maven during build, and are being extracted and loaded (using System.load()) at runtime. The method for that is as follows:
public class EnvironmentUtils {
public static void loadResourceFromJar(String prefix, String suffix) {
String tempFilesDirectory = System.getProperty("java.io.tmpdir");
File tempFile = null;
try {
tempFile = new File(tempFilesDirectory + "/" + prefix + suffix);
tempFile.deleteOnExit();
try (final InputStream inputStream = EnvironmentUtils.class.getClassLoader().
getResourceAsStream(prefix+suffix)) {
if (inputStream == null) {
throw new RuntimeException(prefix + suffix + " was not found inside JAR.");
} else {
Files.copy(inputStream, tempFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
}
}
System.load(tempFile.getAbsolutePath());
} catch (Exception e) {
//Log top 10 lines of stack trace
}
}
}
This method is being called inside a static block for all dependencies:
public class DummyClass {
static {
String sharedLibraryExtension = EnvironmentUtils.getSharedLibraryExtension(); //.so for linux, .dylib for Mac
String jniLibraryExtension = EnvironmentUtils.getJniLibraryExtension(); //.so for linux, .jnilib for Mac
EnvironmentUtils.loadResourceFromJar("libfap", sharedLibraryExtension);
EnvironmentUtils.loadResourceFromJar("libcvrptw_lib", sharedLibraryExtension);
EnvironmentUtils.loadResourceFromJar("libortools", sharedLibraryExtension);
EnvironmentUtils.loadResourceFromJar("libdimacs", sharedLibraryExtension);
EnvironmentUtils.loadResourceFromJar("libjniortools", jniLibraryExtension);
}
}
On running System.load() for libdimacs.so, an UnsatisfiedLinkError is thrown. Stacktrace:
java.lang.UnsatisfiedLinkError: /tmp/libdimacs.so: /tmp/libdimacs.so: undefined symbol: _ZN6google14FlagRegistererC1IbEEPKcS3_S3_PT_S5_
at java.lang.ClassLoader$NativeLibrary.load(Native Method)
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1941)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1824)
at java.lang.Runtime.load0(Runtime.java:809)
at java.lang.System.load(System.java:1086)
at com.(PROJECT_NAME).utils.EnvironmentUtils.loadResourceFromJar(EnvironmentUtils.java:78)
at com.(PROJECT_NAME).DummyClass.<clinit>(DummyClass.java:28)
However, this symbol "_ZN6google14FlagRegistererC1IbEEPKcS3_S3_PT_S5_" is present in libortools.so, which is being loaded before libdimacs. I verified this by running the following command:
objdump -t (LIBRARY_PATH)/libortools.so | grep _ZN6google14FlagRegistererC1IbEEPKcS3_S3_PT_S5_
This gave me the following output:
0000000000ce12cc gw F .text 00000091 _ZN6google14FlagRegistererC1IbEEPKcS3_S3_PT_S5_
So it would seem that the symbol should have been defined at the time of the System.load() call, unless there was some issue in loading the containing object file. To check if the object file had been loaded correctly, I used the approach detailed in this solution. Apart from the class detailed in that answer, I added the following lines after System.load() call in EnvironmentUtils.loadResourceFromJar() to print the most recently loaded library name:
public class EnvironmentUtils {
public static void loadResourceFromJar(String prefix, String suffix) {
...
System.load(tempFile.getAbsolutePath());
final String[] libraries = ClassScope.getLoadedLibraries(ClassLoader.getSystemClassLoader());
System.out.println(libraries[libraries.length - 1]);
}
}
The output (till just before the UnsatisfiedLinkError) is as follows:
/tmp/libfap.so
/tmp/libcvrptw_lib.so
/tmp/libortools.so
So libortools.so seems to be loading correctly, which means the symbol should be loaded in memory. The exact same code is working perfectly with the corresponding Mac (".dylib") dependencies (Built on MacOS Sierra 10.12.5). Would appreciate any advice on resolving this. Thank you.

I'm apologize that the java artifact may be broken currently...
you can use c++filt to demangle the symbol ;)
c++filt _ZN6google14FlagRegistererC1IbEEPKcS3_S3_PT_S5_
google::FlagRegisterer::FlagRegisterer<bool>(char const*, char const*, char const*, bool*, bool*)
In fact gflag has recently change its namespace from google:: to gflags:: and glog or protobobuf? try to find the correct one and I guess it failed...
note: Still not completely sure whose is the bad guy who use the google:: namespace since libortools merge all its static dependencies but I guess now you understand the bug...
note2: I have a patch in mizux/shared branch https://github.com/google/or-tools/commit/805bc0600f4b5645114da704a0eb04a0b1058e28#diff-e8590fe6fb5044985c8bf8c9e73c0d88R114
warning: this branch is currently broken and not ready yet. I'm trying ,for unix, to move from static to dynamic dependencies, so I need to fix all rpath, transitives deps etc... and in the process I also had to fix this issue (that I didn't reproduced while using static dependencies)
If too long to finish (we should create a release 6.7.2 or 6.8 (i.e. new artifact) by the end of May 2018) which maybe only contains this fix and not my branch...

Load jar dynamically at runtime?

My current java project is using methods and variables from another project (same package). Right now the other project's jar has to be in the classpath to work correctly. My problem here is that the name of the jar can and will change because of increasing versions, and because you cannot use wildcards in the manifest classpath, it's impossible to add it to the classpath. So currently the only option of starting my application is using the -cp argument from the command line, manually adding the other jar my project depends on.
To improve this, I wanted to load the jar dynamically and read about using the ClassLoader. I read a lot of examples for it, however I still don't understand how to use it in my case.
What I want is it to load a jar file, lets say, myDependency-2.4.1-SNAPSHOT.jar, but it should be able to just search for a jar file starting with myDependency- because as I already said the version number can change at anytime. Then I should just be able to use it's methods and variables in my Code just like I do now (like ClassInMyDependency.exampleMethod()).
Can anyone help me with this, as I've been searching the web for a few hours now and still don't get how to use the ClassLoader to do what I just explained.
Many thanks in advance

(Applies to Java version 8 and earlier).
Indeed this is occasionally necessary. This is how I do this in production. It uses reflection to circumvent the encapsulation of addURL in the system class loader.
/*
* Adds the supplied Java Archive library to java.class.path. This is benign
* if the library is already loaded.
*/
public static synchronized void loadLibrary(java.io.File jar) throws MyException
{
try {
/*We are using reflection here to circumvent encapsulation; addURL is not public*/
java.net.URLClassLoader loader = (java.net.URLClassLoader)ClassLoader.getSystemClassLoader();
java.net.URL url = jar.toURI().toURL();
/*Disallow if already loaded*/
for (java.net.URL it : java.util.Arrays.asList(loader.getURLs())){
if (it.equals(url)){
return;
}
}
java.lang.reflect.Method method = java.net.URLClassLoader.class.getDeclaredMethod("addURL", new Class[]{java.net.URL.class});
method.setAccessible(true); /*promote the method to public access*/
method.invoke(loader, new Object[]{url});
} catch (final java.lang.NoSuchMethodException |
java.lang.IllegalAccessException |
java.net.MalformedURLException |
java.lang.reflect.InvocationTargetException e){
throw new MyException(e);
}
}

I needed to load a jar file at runtime for both java 8 and java 9+. Here is the method to do it (using Spring Boot 1.5.2 if it may relate).
public static synchronized void loadLibrary(java.io.File jar) {
try {
java.net.URL url = jar.toURI().toURL();
java.lang.reflect.Method method = java.net.URLClassLoader.class.getDeclaredMethod("addURL", new Class[]{java.net.URL.class});
method.setAccessible(true); /*promote the method to public access*/
method.invoke(Thread.currentThread().getContextClassLoader(), new Object[]{url});
} catch (Exception ex) {
throw new RuntimeException("Cannot load library from jar file '" + jar.getAbsolutePath() + "'. Reason: " + ex.getMessage());
}
}