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Unable to compile using Picocli

I'm a dev student
I would love to use Picocli in my project, unfortunately I doesn't understand how to compile using Picocli
I trie to follow the instruction given here https://picocli.info/ or here https://picocli.info/quick-guide.html but the step to compile aren't detailed. I'm not using Gradle nor Maven but they aren't really listed as required.
This is how it tried to compile the Checksum example given in the picocli.info webpage :
jar cf checksum.jar Checksum.java ; jar cf picocli-4.6.1.jar CommandLine.java && echo "hello" > hello
Then I simply copy paste this gived command : https://picocli.info/#_running_the_application
java -cp "picocli-4.6.1.jar:checksum.jar" CheckSum --algorithm SHA-1 hello
And get the following result :
Error: Could not find or load main class CheckSum
Caused by: java.lang.ClassNotFoundException: CheckSum
I tried to compile everything myself and then add the .jar like this :
java CheckSum -jar picocli-4.6.1.jar
But then the error output looks like this:
Exception in thread "main" java.lang.NoClassDefFoundError: picocli/CommandLine
at CheckSum.main(Checksum.java:33)
Caused by: java.lang.ClassNotFoundException: picocli.CommandLine
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
... 1 more
Witch I don't understand since I added the dependency.
What am I missing ?
Thanks in advance

The problem is that the command jar cf checksum.jar Checksum.java only creates a jar file (jar files are very similar to zip files) that contains the Checksum.java source file.
What you want to do instead is compile the source code first. After that, we can put the resulting Checksum.class file (note the .class extension instead of the .java extension) in the checksum.jar. The Java SDK includes the javac tool that can be used to compile the source code. Detailed steps follow below.
First, open a terminal window and navigate to a directory that contains both the Checksum.java source file and the picocli-4.6.1.jar library.
Now, the command to compile (on Windows) is:
javac -cp .;picocli-4.6.1.jar Checksum.java
Linux uses : as path separator instead of ;, so on Linux, the command to compile is:
javac -cp .:picocli-4.6.1.jar Checksum.java
The -cp option allows you to specify the classpath, which should contain the directories and jar/zip files containing any other class files that your project uses/depends on. Since Checksum.java uses the picocli classes, we put the picocli jar in the classpath. Also add the current directory . to the classpath when the current directory contains any classes. I just add . habitually now.
Now, if you list the files in the current directory, you should see that a file Checksum.class has been created in this directory.
Our Checksum class has a main method, so we can now run the program with the java tool:
On Windows:
java -cp .;picocli-4.6.1.jar Checksum
On Linux:
java -cp .:picocli-4.6.1.jar Checksum
Note that when running the program with java you specify the class name Checksum, not the file name Checksum.class.
You can pass arguments to the Checksum program by passing them on the command line immediately following the class name:
java -cp .:picocli-4.6.1.jar Checksum --algorithm=SHA-1 /path/to/hello
When your project grows, you may want to keep the source code and the compiled class files in separate directories. The javac compile utility has a -d option where you can specify the destination for the compiled class files. For example:
javac -cp picocli-4.6.1.jar:otherlib.jar -d /destination/path /path/to/source/*.java
This should generate .class files for the specified source files in the specified destination directory (/destination/path in the example above).
When you have many class files, you may want to bundle them in a single jar file. You can use the jar command for that. I often use the options -v (verbose) -c (create) -f (jar file name) when creating a jar for the compiled class files. For example:
jar -cvf MyJar.jar /destination/path/*.class /destination/path2/*.class
Enjoy!

No class def found error even though the jar is added to classpath

I am running Java program from command line. I am referring to only 1 external jar file. i have added entire path to that jar in classpath. even then i get no class def found error while running program in command line. Program compiles without any error.

I think you complied and run the Java program like this
javac -cp fullyqualifiedPathToExternalJar yourfilepath/filename.java
java -cp fullyqualifiedPathToExternalJar yourfilepath/filename
This is totally wrong. When you compiled and run in this manner program compile successfully but not run. This because you have to follow the syntax of java command Properly.
for compiling its Ok.
javac -cp fullyqualifiedPathToExternalJar yourfilepath/filename.java
To run the program you have to add your file path to the classpath:
java -cp fullyqualifiedPathToExternalJar;yourfilepath filename.java //in windows
java -cp fullyqualifiedPathToExternalJar:yourfilepath filename.java //in linux
The syntax is
javac example.java
java example
with folderpath
javac /home/admin/example.java
java -cp /home/admin example//only class name

Might be the chances of jar's compatibility issue. check yous inter dependent jar versions.

Error when try to run my project in cmd

I have a structure code like this :
I want to run my program using mcd using javac, like this : javac ListenerZipFile.java. The result like :
Why i can't run my program?

you are using a package without telling javac where it is located (jnotify for example).
you'd have to use it like:
javac -classpath "path/to/jnotify-0.94.jar" test.java

There are 2 problems here.
Incorrect directory location for compiling packed classes.
classpath no set correctly.
Consider you have, source_dir = D:\~\~\src, jar_location = D:\~\~\lib and package is com.example then your steps to compile are:
cd to $source_dir
$source_dir> set classpath=.;jar_location
$source_dir> javac com\example\Examples1.java or $source_dir> javac com\example\*.java
As per path shared, command to compile should be :
cd C:\ListenerZipfile\src
javac -cp .;C:\ListenerZipfile\lib\*.jar com\sigma\main\ListenerZipFile.java
Command to run java program with above path:
java -cp .;C:\ListenerZipfile\lib\*.jar com.sigma.main.ListenerZipFile

if you are using eclipse (from the screen shot i think you do) then
right click on your project->Properties->Java Build Path, click on Libraries tab->click on "Add External JARs" button-> pick your jar and click OK to close all windows.
This should solve your problem, if your problem is jar dependencies

How to compile and run HelloWorld.java example from Sphinx4 without and IDE in Linux?

I have been testing the examples (HelloWorld.java) from Sphinx4 with Eclipse, but I would like to compile and run them from the command line.
The application needs 5 .jars to be able to run, I have read that in order to compile a java class with multiple .jars I need to execute the following command (as an example I will show short names):
javac -cp one.jar:two.jar:three.jar:four.jar:five.jar HelloWorld.java
The console does not throw any error messages:
parias001#parias001-pc:~/Projects/citadel_voices/sphinx_test > javac -cp jsapi.jar:sphinx4.jar:TIDIGITS_8gau_13dCep_16k_40mel_130Hz_6800Hz.jar:WSJ_8gau_13dCep_8kHz_31mel_200Hz_3500Hz.jar:WSJ_8gau_13dCep_16k_40mel_130Hz_6800Hz.jar HelloWorld.java
parias001#parias001-pc:~/Projects/citadel_voices/sphinx_test >
I think that the compilation succeeded. Now I would like to run the application, I read that in order to do this, I have to execute the command as follows (Using short name example as before):
java -cp one.jar:two.jar:three.jar:four.jar:five.jar HelloWorld
This is the message that the console throws:
parias001#parias001-pc:~/Projects/citadel_voices/sphinx_test > java -cp jsapi.jar:sphinx4.jar:TIDIGITS_8gau_13dCep_16k_40mel_130Hz_6800Hz.jar:WSJ_8gau_13dCep_8kHz_31mel_200Hz_3500Hz.jar:WSJ_8gau_13dCep_16k_40mel_130Hz_6800Hz.jar HelloWorld
Error: Could not find or load main class HelloWorld
I don't know what is going on here, I should also say that I do not have a lot of experience using external .jars.
The names of the .jars are:
jsapi.jar
sphinx4.jar
TIDIGITS_8gau_13dCep_16k_40mel_130Hz_6800Hz.jar
WSJ_8gau_13dCep_8kHz_31mel_200Hz_3500Hz.jar
WSJ_8gau_13dCep_16k_40mel_130Hz_6800Hz.jar
I appreciate any help you can give me.

You have to include current directory in classpath:
java -cp .:one.jar:two.jar:three.jar:four.jar:five.jar HelloWorld
Note the leading .:
From this reference:
The default class path is the current directory. Setting the CLASSPATH variable or using the -classpath command-line option overrides that default, so if you want to include the current directory in the search path, you must include "." in the new settings.

cannot execute binary file: Exec format error

I ran a java executable file using the following command
java -cp .;aa/bb/cc/dd/Main.jar aa.bb.cc.dd.Main
where aa.bb.cc.dd is the package that has all the .java, .class, and Main.jar files
and this package is inside the src folder from where I am running this command.
I am getting an error
cannot execute binary file: Exec format error
Can anyone tell me where I am going wrong.

Semi-colon in bash is used to separate commands. So in your case
java -cp .;aa/bb/cc/dd/Main.jar aa.bb.cc.dd.Main
java -cp . and aa/bb/cc/dd/Main.jar aa.bb.cc.dd.Main are considered as two separate commands and executed in sequence.
The issue can be fixed by changing the ";" to ":".
The path delimiter for java class path is ":" and not ";".