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Java Jar file main class run when runs from command line, but not from Windows batch file

I'm re-using a standalone Swing-based Java class which backs up and restores mysql databases.
I've tested running it from a Windows batch file (.bat) on my dev system, and it works there.
But, if I run the batch file on a different Windows , I get a "main class not found" exception.
However, when I run the command directly on the command line, it works.
The command in the batch file to run it is:
java -cp lda-services.jar;bip-services-1.6.0.0-SNAPSHOT.jar;decryptor-1.6.0.0-SNAPSHOT.jar;slf4j-api-1.7.31.jar;commons-io-2.6.jar com.ilcore.util.SosaMaintenanceJFrame
The SosaMaintenanceJFrame class is contained in the lda-services jar.
Here's the error message:
Error: Could not find or load main class com.ilcore.util.SosaMaintenanceJFrame
Caused by: java.lang.ClassNotFoundException: com.ilcore.util.SosaMaintenanceJFrame
The class is definitely in the jar file, as I've extracted it the file and seen it.
Any thoughts on why this would be happening? I need to run inside a batch file so the user can just click on it to run it.

Most likely explanation
Your paths are relative, which means that the batch file isn't going to work unless you run it from the right place. In general, having a batch file that has an invisible rider stapled to it with: "I break in mysterious ways if not run from the appropriate dir" is a crappy batch file - make it better.
Better solution
Or, even better, get rid of it. You don't need batch files to distribute java programs.
Proper ways to distribute java programs:
The modern take is very very different from what you have here: JREs are dead, you must ship an installer that does the whole thing, notably including a java runtime (no longer called a JRE, and one you ship and keep up to date if relevant). That's perhaps a bridge too far for what you're doing here. Relevant tools include jlink.
A slightly less modern take involves jars with manifests:
Your jar file should contain a manifest. This manifest must contain 2 relevant entries:
Class-Path: lda-services.jar bip-services-1.6.0.0-SNAPSHOT.jar decryptor-1.6.0.0-SNAPSHOT.jar slf4j-api-1.7.31.jar commons-io-2.6.jar
and
Main-Class: com.ilcore.util.SosaMaintenanceJFrame
You can use jar's -m switch, or just include the manifest (it's just a file in the jar): it's at META_INF/MANIFEST.MF and it's a text file, each line is an entry, and an entry consists of a key: value pair.
When a jar contains this, just double clicking the jar and running java -jar thejar.jar will then take care of it all: Java will load the stated jars as part of the classpath, and these, crucially, are resolved as paths relative to the directory the jar is in, so it DOES work when you try to launch them from elsewhere, i.e. if you do:
C:
CD \
java -jar "c:\Program Files\MyApp\myapp.jar"
it works fine, whereas that batch script would fail due to being in the wrong place.
Build systems let you define the manifest too, check your build systems docs for how to do this, it'll be easy, and there are tons of tutorials if you search the web for e.g. 'manifest executable jar maven' or whatnot.
You can consider making a shaded jar. But I wouldn't.
A shaded jar takes all your dependencies and packs them into your main jar, so that there is only one jar. There is now no need for a Class-Path entry (the jar you run is obviously already on the classpath and there's nothing else to include) and your app is shipped as 'just' a single jar file.
But this is mostly a red herring: There are no consumer JREs anymore so you've made the user experience from a D- to a D. If you actually care about giving your users a nice experience, there's no getting around an installation process of some sort and once you have that, having the separate jars is no longer a problem. Separate jars are less hairy when signed jars are involved, are much easier to keep up to date, and have a significantly faster turnaround (when you build your stuff and want to ship what you built, shading takes ages, so it's nice to cut that step out). The faster your CI system tells you about failing tests, the better.
Meet in the middle
You don't have to upgrade to modules and the like. What you can do instead is use something like launch4j. The aim is to end up with a zip file along with the installation instructions: Make a dir somewhere. unzip this zip in it. Doubleclick 'myapp.exe'. Done.
The zip would contain an entire JRE, all your jar file deps, and your main app, and an exe file which launch4j made for you, that launches your app using the JRE packed into the jar. This means you know exactly which JRE is being used, and it'll work even on systems that didn't have one installed yet (which, these days, should be all of them - the notion of 'end user downloads a JRE from oracle and the user + oracle work together to keep that thing up to date and security-issue-free', is dead).
The fact that it's an EXE is nice: Now if the user e.g. alt+tabs through their apps, they get your app, with your name, and your icon, instead of 'javaw.exe' with an ugly coffee mug logo.

But when I try running it from the jar file generated by Maven, however, I get a "class not found" exception.
Even if you didn't get that error, you'd get another one unless you'd used Maven Shade, as that's the only way you're going to run that with a single jar. My guess as to why that particular error occurs is that the app class you're attempting to run is in fact in one of the *SNAPSHOT* jars

Make a .jar file that "just runs" everywhere?

I've written a few java applications (desktop, no browser involved) for friends, some of whom are less technical than I am. They use Windows, Linux and Macs. Originally I just used javac to generate bunches of .class files, zipped it all up and had them unpack it all. It works, but they had to install the JRE (terrifying for some), write a script to run java or javaw followed by command line args, app name, more arguments (incomprehensible for some), mark the script executable... I got mocked, somewhat rightfully, for a geek solution. They wanted to download from a website, doubleclick and be up and running.
I thought creating a .jar file would be the solution. It didn't help. In Eclipse, the options seem to be "create a jar file", which lets me include the handful of resources (.png files mostly) the apps needs, but the result isn't runnable from a command line. Or, create an executable .jar file, which doesn't seem (at least from Eclipse) to have a way to include resources - and the resulting .jar file doesn't start when double-clicked, even when I set the execute bit, even though the default run environment points to the Java suit. Even with a .jar file, I'm stuck with having them script "java -jar App...", and that's pretty much a dealbreaker.
I'm missing something. The point of Java is platform independence. Is there a platform independent way to have them download a single file, double click it and have it off and running?

If you are trying to create a runnable jar file from your project in Eclipse, you have to select that option when exporting. You can do this by Export > Java > Runnable Jar File. If you only select the Jar File option, you won't be able to run it.
If you want to wrap your application as a .exe, you can use launch4j. Here's a thread that explains it a little more and has some other options.

the .jar file does not execute when I click on it

I know this question would sound very stupid, but this is my first java program after all.
K, the question is, when type this: java -jar JavaApplicationTest.jar the program executes without problems, but when I go to the folder where the JavaApplicationTest.jar file is, and click on it, it does not execute. I thought that .jar files were like .exe file, are they? I mean, in the way that we click on them and the program runs; 'cos the java virtual machine is running in the back ground.
Please, any help would be very much appreciated.

No, they aren't exactly like .exe. Only .exe is an .exe.
When you execute a JAR file, it's the Java JVM that's running, not your JAR file. The JVM opens the JAR, loads the .class byte code, and executes the main class that you specified in the META-INF.
I'm guessing that your Windows operating system is doing something besides running the JVM when you double click. Try right clicking and seeing what options your Windows operating system presents to you. If one of them is to unzip the file, you'll have to add running the JVM as another choice.

The jar-file runs. But there's a big difference between:
java -jar someJar and someJar.jar/respectively double-clicking on the jar.
The full command launches the jar in the same commandline, in which you have entered the command. Double-clicking on the jar creates a process aswell. But with a completely separate console-window that is hidden.

Java archive or jar is an archive of compiled java byte code and resources which can be run on a java virtual machine. ".exe" is a windows extension for directly executable code mostly used by installers or programs that do not need to be installed.

Running java from a bat file in such a way that path doesn't need to be specified

I think I have seen this done, but am not sure where. What I want to do is to create a bat file I can package with my class files when sending to a friend to show them progress/ask advice on non programming matters. My friend is not very handy when it comes to code and doesn't like changing computer settings. Just using java myClass as a command line won't work here because although my friend does have java installed, he has not set his windows environment variables so his command prompt knows where to find java.
What kind of line would I need to add to my batch file to make it so it can compensate for problems like this?

Create a manifest file (manifest.txt):
Main-Class: com.mycompany.myapp.MyMainClass
Package your app as a jar:
jar cfm myjarfile.jar manifest.txt *.class
Create a batch file:
start myjarfile.jar

If it is about sharing and running a single java file without jar dependencies. And you are only worried about the java runtime environment setup, then you can use online java code compilers and executors. Here is one:
http://javalaunch.com/JavaLaunch.jsp
You can google for more!

Use an IDE, NetBeans or eclipse and package your files as a Jar file.. that can be executed directly and you do not need to worry about dependencies, other classes or libraries.

How to load a library that depends on another library, all from a jar file

I would like to ship my application as a self-contained jar file. The jar file should contain all the class files, as well as two shared libraries. One of these shared libraries is written for the JNI and is essentially an indirection to the other one (which is 100% C).
I have first tried running my jar file without the libraries, but having them accessible through the LD_LIBRARY_PATH environment variable. That worked fine.
I then put the JNI library into the jar file. I have read about loading libraries from jar files by copying them first to some temporary directory, and that worked well for me (note that the 100% C library was, I suppose, loaded as before).
Now I want to put both libraries into the jar, but I don't understand how I can make sure that they will both be loaded. Sure I can copy them both to a temporary directory, but when I load the "indirection" one, it always gives me:
java.lang.UnsatisfiedLinkError: /tmp/.../libindirect.so: /libpure.so: cannot open shared object file: No such file or directory
I've tried to force the JVM to load the "100% C" library first by explicitely calling System.load(...) on its temporary file, but that didn't work better. I suspect the system is looking for it when resolving the links in libindirect.so but doesn't care about what the JVM loaded.
Can anyone help me on that one?
Thanks

One way would be to spawn another Java process from the first, generating the appropriate invocation script.
The jar is invoked by the user
The libraries are extracted to a temp directory
A (bash) script is written to the temp directory
this sets/exports the necessary environment variables
this launches the second JRE instance
The code makes the script executable
The code invokes the script
I know, spawning two JRE instances to launch one app would not be my first choice either.

If you are using Eclipse IDE, then this answer might help you.
I had same problem in eclipse windows that I couldn't added dependant .class files from the JNI.
After searching for a while I came to know that "Its a known bug inside Eclipse", In order resolve the same, I ported all the code to NetBeans IDE.
Can not add all the classes files from the JNI folder in Eclipse (JAVA, Windows 7)