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I'm trying to run java from cmd with help of VSCode and it doesn't find the other classes I created [duplicate]

At the moment I am looking for another way to run my Java program from command line, other than adding it to a JAR file. My program has the following number of classes:
The name of the program file - MyProgram
Main class - Server1
second class - Client Handler
Package name - Items
3rd class - User1
4th class - User2
The main class and client handler alongside the package will have to run first in order for user 1 & user 2 to run, because they are client classes and are dependent on the main class.

javac *.java // compliles all java files in the dir
java MyClass // runs the particular file
If one class is dependent on another class that hasn't been compiled yet, the program won't run. So you should compile all files before trying to run the program dependent on other files.
If your files are packaged, then something like this
javac com.mypackage/.*java
java com.mypackage.MyClass

you must ensure that you add the location of your .class file to your classpath. So, if its in the current folder then add . to your classpath. Note that the windows classpath separator is a semi-colon ie ;
javac -cp . PackageName/*.java
java -cp . PackageName/ClassName_Having_main
Example. Suppose you have the following
Package Named: com.test
Class Name: Hello (Having main)
Java file is located inside "src/com/test/Hello.java"
then, from outside directory:
$ cd src
$ javac -cp . com/test/*.java
$ java -cp . com/test/Hello
Note that you can add -d to specify output directory of your class files whenever compiling
$ javac -d output_directory -cp . com/test/Hello
In windows the same thing will be working too, I already tried
Check out this from Oracle official site

Once you compile your code, you then run this from the top level:
java -cp . com.myprogram.MyProgram
That order thing you describe doesn't matter. They all get compiled together, and MyProgram will reference Server1, etc.

It may be more then you want to tackle right now but you might want to consider a build system like Maven. To start try out; How do I make my first Maven project?
You can use it to predefine the build order and if you want have it create a jar for you (or not).

Sounds like you will just need to open multiple command prompts and compile and run them in the order you need them to run. Let me know if I misunderstood question.

TO EXECUTE TWO JAVA PROGRAMS WHICH DEPENDS TO EACH OTHER.
(for example:two files Complex.java and Solution.java, where Soultion.java depends upon Complex.java.
So Complex.java should be compiled first and then the class file of Complex must be linked with Solution.java and then Solution.class must be executed for Output.)
REFER THE IMAGE WITH SYNTAX.
STEP 1:
COMPILE Complex.java
compiling Complex.java
syntax-
javac -d [path_where_class_File_build] [path_of_the_file\filename.java]
(Solution.java and Complex.java are Linked. ie-Solution.java calls Complex.java)
STEP 2:
COMPILE Solution.java
compiling Solution.java with linking Complex.class
with linking Complex.class(above created in step 1)
syntax-
javac -d [path_where_class_File_build] -cp [path_of_the_first_class_created] [path_of_the_file\filename.java]]
STEP 3:
EXECUTE THE Solution.class
java -cp [path_of_second_class_created] [class_Name]
(created in Step 3)

Cannot run Java app on cmd using Java11 and Windows

I ahve tried several approaches as on How do I run a Java program from the command line on Windows? and create exactly the same class and packages to use the same things.
Here is the sample class located on C:\SimpleJavaProject\src\com\hello\programs:
package com.hello.programs;
public class ABC {
public static void main(String[] args) {
System.out.println("Hello world");
}
}
Then I compile it in the usual way:
C:\SimpleJavaProject\src\com\hello\programs > javac ABC.java
Later, run it by giving the package name and then my java class name:
C:\SimpleJavaProject\src > java com.hello.programs.ABC
In each time I try to run java app, I get "Error: Could not find or load main class com.hello.programs.ABC" error. Then have a look at What does “Could not find or load main class” mean? page and tried some approaches on that page. But still the same error.
It is too simple, but still I have not managed to run the simple app yet. So, how to fix this problem? And after running the app, how can I pass args on cmd?
Update: I could already generate ABC.class file by running the following command. BUT, I cannot run the app and see the "Hello world" on the console.
cd C:\SimpleJavaProject\src\com\hello\programs
javac ABC.java
--> generates ABC.class in C:\SimpleJavaProject\src\com\hello\programs

java com.hello.programs.ABC
When you run this, java is going to check each and every CLASSPATH path for that + /com/hello/programs/ABC.class, will load that, and then run it.
This must mean that either:
[A] Your classpath does not include the current directory; The fix is java -cp . com.hello.programs.ABC.
[B] you didn't do what you wrote, and e.g. dir com/hello/programs.ABC.class prints nothing.
Note that you're not doing it right; a class file should never be in a directory path that includes src. If you don't want to bother with build tools like maven or gradle, I strongly suggest you don't bother with a src dir then either. If you must, the -d option can be passed to javac to tell it where tou put the file. If you want to separate source and class files, then that should be targeting a directory named bin or build or whatnot (a sibling of the src dir).

When you use javac ABC.java you are compiling the class, and javac places it in the current directory.
So java com.hello.programs.ABC would not work (because com/hello/programs/ABC.class file does not exists).
You can use the javac -d flag:
-d <directory> Specify where to place generated class files
For instance:
> javac -d . ABC.java
> java com.hello.programs.ABC
Hello world
> cd com\hello\programs
> dir
ABC.class
Would work, because javac did place ABC in com/hello/programs.
Update: For clarity, once you compiled using javac -d . ABC.java you can run it using java com.hello.programs.ABC and you should see Hello world in the screen.

How to use javac with jars and packages

I'm trying to run java from the command line, and haven't had to include extra packages with the javac command before and I can't figure out what I'm doing wrong.
I'm running javac -d bin -cp jar1:jar2:...:jarN:PackageName MyClass.java but I'm still getting an error: package PackageName does not exist
I'm using the absolute paths for everything, and I also tried individually listing the java files inside the package but that didn't work either. I'm using a colon since I'm on a mac.
Anyone know what I am doing wrong? Thanks for any help!

I realized that I needed to compile the java files in PackageName before I could compile MyClass.java, which depended on them. So what I needed to do was: javac -d bin -cp jar1:jar2:...:jarN PackageName/*.java and then I could compile MyClass.java with bin added to the classpath as well as the jars.

Cannot run a .jar file

I'm having issues when I try to execute a .jar file. I always get the message from the command prompt "cannot find or load main class" every time I try to run the file I have just compiled.
I have tried the following(using the command prompt and saving the java code with Notepad++ and creating the manifest.txt file in the same folder where the .java code was saved):
javac classname.java
java cfm classname.jar manifest.txt classname.class
java -jar classname
I have also tried:
javac classname.java
java classname
And:
java packagename.classname
After compiling the .java file
I know there are hundreds of questions like this in the forums, but I have looked everywhere and I keep getting the same error. I just cannot run the .jar file even after I create it.
It's probably something I have missed but I am out of ideas.
Manifest:
Main-Class: classname

Let's see.
java -jar classname.jar
would work if your MANIFEST.MF calls out the correct class.
java -cp classname.jar my.package.MyClass
would work in any case.

Access another java file in a java file

I know this question has been asked and answered a number of times. But I somehow am not able to get this right. I have a package having the following structure
model/
InputDetails.java
RelationDetails.java
Now the file RelationDetails has the following structure:
package model;
public class RelationDetails {
....
}
And the file InputDetails has the following structure
package model;
public class InputDetails {
.....
}
Now I have compiled the RelationDetails.java file that creates a RelationDetails.class file in the same directory.
But when I try to compile the InputDetails.java file, It shows the error
Symbol not found
wherever RelationDetails has been used. Where am I going wrong??

I'd recommend using an IDE like Eclipse or IntelliJ IDEA. They will do the compiling for you. Or use Ant, Gradle or Maven to compile. I am a professional Java developer and I cannot remember the last time I used javac from the command line. There's no need for it.
If you insist on using javac directly, either compile both files together from the appropriate source folder (the directory above "model").:
javac "model/InputDetails.java" "model/RelationDetails.java"
Or, if you want to compile them separately:
javac -classpath . "model/InputDetails.java"
javac -classpath . "model/RelationDetails.java"
The -classpath . bit adds the current folder to the classpath for the javac executable, so it can find the previously compiled class and you won't get the 'Symbol not found' errors.

$ pwd
/tmp/model
$ ls
InputDetails.java RelationDetails.java
$ javac InputDetails.java RelationDetails.java
$ ls *.class
InputDetails.class RelationDetails.class

I am just tried in my eclipse nothing will be showing errors, better to user Eclipse or STS they will help you like this problems easily I think so..

compile with fully qualifier name.
javac model\YourClass.java