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How to run java project from command line (works fine in eclipse, gradle)

I'v got a simple java program. I'm developing in Eclipse, using gradle, and I'm logging with log4j2. This all works fine.
When I come to run from the command line, I do a gradlew build which works, but when I run the jar I get an error:
java -jar build\libs\testproj.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/logging/log4j/LogManager
at com.xxxxxx.practice.App.<clinit>(App.java:17)
Caused by: java.lang.ClassNotFoundException: org.apache.logging.log4j.LogManager
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:602)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
... 1 more
I can see a bunch of log4j files in my userprofile.gradle folder, and I could run a gradle dist task and then got and unzip the resulting zip file and then point at the contents of that, but if there some way of avoiding this? Surely there's something I can add to the manifest or something so that I can run from the command line at will with no overhead?
To be clear, it's just the logging that has this problem. Other than that it runs, the tests work etc from the command line, and the logging works fine from eclipse.

Someplace in your eclipse project, you'll find a library (these end in .jar) named log4j.jar or org.apache.logging-log4j.jar or log4j-api.jar or something along those lines.
This jar contains the classes that are missing when you run this on the command line. Try it: jar tvf log4j.jar prints the contents of the jar and you'll find it contains, for example, org/apache/logging/log4j/LogManager.class.
During compilation and during running a java app, this class needs to be on the classpath. Eclipse is taking care of the compilation part of it.
If you run java as java com.foo.ClassName, the classpath is defined by the -cp parameter: java -cp testproj.jar:log4j.jar com.foo.yourapp.TestApp would work (use semicolon on windows instead). If you don't specify it, the system environment variable CLASSPATH is used, but you don't want that (you can run multiple java apps on one machine after all, so a global setting makes little sense).
If you run java using java -jar myjar.jar however, the classpath is solely taken from the jar file itself; inside the jar file is a file called META-INF/MANIFEST.MF and it contains (in text) key/value pairs. The relevant one is the Class-Path: foo.jar bar.jar entry: Space-separated listings of jar files, relative to the dir your jar is in.
You cannot use the -cp option when using the -jar option; the -cp option is ignored.
So, next steps:
I don't know if gradle made the Class-Path entry correctly. Best option is to use the jar or zip tool to unpack your jar to check that MANIFEST.MF file and see what's there. If there is, say, Class-Path: lib/log4j.jar in that file, then make sure that if testapp.jar is at /Users/Dev123456/project/testapp.jar, that that log4j jar is at /Users/Dev123456/project/lib/log4j.jar. If there is no class-path entry, then the error lies in your gradle config; you'd have to post your build.gradle file in that case.
There are 'striper plugins' which mix all the various jars together in one giant jar. This is usually a bad idea (it just makes the jar itself humongous, and makes builds take longer. If you're deploying java code to a server, you can manage the Class-Path entry by yourself, and if you are making a desktop app, you need an installer which... can manage the class-path stuff just as well. Really no reason to use stripers). I advise against using these.
Just run with java -cp yourapp.jar:dep1.jar:dep2.jar com.foo.fullyqualified.ClassName instead.

Try to run your jar by specifying Log4j jar as well in classpath and then mention your MainClass from testproj.jar :
java -cp build\libs\testproj.jar:build\libs\log4j.jar com.package.MainClass

Compile project and include libraries using batch script

In CMD I compile project with including libraries
java -cp app.jar;libs/*;. com.app.Main
and it works, but I want create BATCH script, which do exactly the same. I create test.bat and put code like below:
#ECHO off
java -cp app.jar;libs/*;. com.app.Main
PAUSE
But when I run the test.bat the CMD was shown and there is information "Error: Could not find or load main class com.app.Main".
BATCH script is located at the same folder as app.jar and libs folder.
What is wrong with this batch script?

Probably the characters on the compile line are significant to the batch interpreter; try putting the classpath in double quotes.

After Java 6, Classpaths could be built by using wildcard characters.
You can create a directory named classpath and put your JARs inside it. Then you can create your .bat file like this:
#ECHO off
java -cp .;classpath/* com.app.Main
pause
You should have a structure like this:
com
`---app
`---Main.java
classpath
`---your-crital-code-1.0.jar
compile.bat
I see that a lot of people are asking this question on StackOverflow, so here is a little tip for you guys.
I usually avoid using the cd command, as it may create some hassle. In windows, you can Shift + Right Click to open a command window in a particular directory.
I always prefer relative paths over absolutes, so that I don't get into hassle of managing long paths.
Here is a little program that deals with this kind of problem. You can always refer to and contribute to it so that we can make good examples for Java beginners :)

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.

java.lang.NoClassDefFoundError. Class not found during runtime.

I am working on eclipse, and I have the need to use external library's. For example Jsoup and JXL.
Now what I have done so far is: First created a "lib" folder in my project folder. Afterwards in eclipse, click on project properties, Libraries tab, add external jar and added the jar in the lib folder.
So this solve my compilation issue. Now, when I run the program (I go to project/bin and in the console execute: java ProgramName ; I get
java.lang.NoClassDefFoundError:
Now to testing, I added the Jar file to the folder where Main.java is and Now, I have been able to run the program doing the following:
javac -classpath ./path/to/jar Main.java
java -classpath ./path/to/jar:. Main
And this works.
So the first thing that comes to mind is that I have to tell java where to find the respective libraries. If this is correct? How do I do it?
java -cp ???(dont know what to put here)
But moreover. I have another issue. I am writing this program in a computer, but I am going to use it in other which probably don't have those libraries. How do I solve this issue?

I like to use something like the following:
java -cp myjar.jar;lib/*.jar com.foo.bar.MyClass
This adds not only my jar to the classpath but those in the lib directory as well.
If you want to run your jar on another computer, you will need those jars as well, you cant just have your jar. Why not just also package your lib directory along with it?

To get your program to run you have two paths to worry about
The path to the jar files that are your applications dependencies (like jsoup.jar) (lets call this lib)
The path to the directory containing the classes of your app (lets call this classes)
The general form of the command line you need is:
java -cp lib/jsoup.jar:classes Main
If you have more libs
java -cp lib/jsoup.jar:lib/jxl.jar:classes Main
A general note on packaging your app for release to other computers. You might want to consider making a jar of your own app, probably best done using http://ant.apache.org/manual/Tasks/jar.html
Another option is to produce a "one jar", which makes one large jar, bundling in all the classes you need from your libs and all the classes in your app. You can then make the jar executable for a nice out of the box solution. Have a look at http://one-jar.sourceforge.net/ and https://code.google.com/p/jarjar/

if you have this structure:
project folder
... code
... libs
then from the code folder:
javac -cp .;../libs/*.jar yourmainclass.java
java -cp .;../libs/*.jar yourmainclass
When you need to compile and run this project, take all the folder and do the same in other machine.

Java - Difficulty installing program from 3 separate .jar files (involves CLASSPATH)

I'm having a little trouble running some Java code, which requires three .jar files to be used. I'm at a lost as to what to do with them--I've tried setting the CLASSPATH (and following the instructions for how to do so in the readme files), but to no avail.
I was wondering if someone could walk me through it? I'd imagine three .jar files would be an easy install for someone who knows what they're doing.
If it helps, I'm using Ubuntu pretty much right out of the box (but I do have JDK and Eclipse installed!)
Runtime library: http://cogcomp.cs.illinois.edu/download/software/20
Additional .jar needed: http://cogcomp.cs.illinois.edu/download/software/23
Program I ultimately need to run: http://cogcomp.cs.illinois.edu/download/software/26
If you're willing to help, I can't thank you enough--you deserve a million kudos!
G

Those are all JAR files. When you execute a JAR file by doubleclicking or using java -jar, the CLASSPATH environment variable and the -cp and -classpath arguments are ignored. The classpath should be defninied in META-INF/MANIFEST.MF file of the JAR. In this particular case, only the second and third JAR have a Class-Path entry in the manifest file:
Class-Path: LBJ2Library.jar
Which is the first JAR. The classpath is telling that it is expecting the LBJ2Library.jar to be in the same folder as the JAR you'd like to execute (either the second or third one).
So, just drop them all in the same folder and execute by java -jar LBJPOS.jar.

If you are using java -jar to run your jar files, then the CLASSPATH variable is ignored. If you are using java -jar, you have two options:
Combine the three jars into one jar.
Run the main class directory and don't use -jar.

Use of the CLASSPATH environment variable is generally discouraged nowadays. This is how it's done (on Linux):
java -cp library1.jar:library2.jar:mainapp.jar <fully qualified name of main class>

You need to set the CLASSPATH .place all the 3 jars in a folder , name it as lib
See below to set classpath
set CLASSPATH=%CLASSPATH%:lib;