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VS Code runs .java files without the producing .class files

I have some basic java knowledge and i decided to switch from Intellij to VS Code. I know how to compile and run a java file (which may use other imported .java files) from the terminal, but i want to run a java program using the run icon inside vs code.
I'm not a 100% sure, but i think that in order to run a java program inside vs code you need a extension. For this reason i downloaded the Java extension pack. Note that i already have installed the latest jdk on my computer.
After i installed the plugin, i could run the program using the "run without debugging"/clicking in the run icon. However, no .class files are produced. I control+h but there isnt any hidden folder that vs code may drop the .class files.
How does the program run in the first place?
How can i config vs code in order to compile the java files before running the one that has the main function?

Basically, when you run a java file normally, you compile it with javac and then run it with java (or something along those lines, there are many different variations of possible ways to do it). If you go ahead and try, it is possible to run java filename.java and skip the normal javac step. In the case of VSCode, it will differ based on what extensions you have, but some may run the code with a simple java filename.java and others may have different settings set. If you take a look at your extension preferences as well as your preferences for java by searching your settings, there may be an option, such as "Java Source Paths" enabled which changed where compiled files are saved by VSCode.

If your project is a folder containing Java source files. And no build tools(Maven/Gradle) are used.
If that is the case, you can trigger the command Java: Configure Classpath, then find the section output and then set a relative path to your workspace.
The output files are by default stored inside the workspace storage.
If after triggering the command, what you see is the native vs code setting page. Then try to search java.project.outputPath and then set a relative path to it.

How do I make a final executable file for my Java program?

I created a tic-tac-toe game in Java. It runs fine on Eclipse.
How do I compile this file (which is currently a .java file) to the standard file format of Java applications, so it can be run from the desktop like a normal program?
What is the standard file type for the final executable Java application? What should be the file type if I want people to easily and without any computer knowledge run my program on their computers?

with eclipse right click on your project. then export it as a runnable .jar file.
Project Right Click > Export > Runnable .jar File.
First choose your project under "Launch configuration", then choose your destination.
After that click finish. Your program should be in your destination folder. Double click to start (just like an .exe file)
For example: If you export it to your desktop, and you name it "TicTacToe", the file on your desktop is "TicTacToe.jar" - ".jar" is your executable file
Done

You have to compile your java class first
javac TicTac.java
and then execute it
java TicTac
Note: that here you provide the name of the class with the main method!

As the other answers indicated, you can create an executable jar using eclipse (or a number of other tools). What these tools are doing under the hood is defining the Main-Class: attribute in the jar's manifest.
In Windows, your users can double click on an executable .jar to launch it, as long as the file associations are configured correctly. However this may not be obvious to windows users who are trained to expect some sort of .exe extension.
To solve this, you could use launch4j to wrap your executable jar in a windows executable. Note: this doesn't change your java application into a native application (it still requires the JVM, etc), it simply makes it launch more like a native application.

For deploying Java desktop apps., the best option is usually to install the app. using Java Web Start. JWS works on Windows, OS X & *nix.
Note that JWS is more effort for us to deploy (it involves not only Jarring and signing the code, but creating a JNLP launch file and a page on the net or network to check that Java is installed & serve the files to the user), but is super easy for the end user.
If there is a JWS deployment, the Jar does not have to be an 'executable Jar' as described in the other answers.

The command should be javac yourFile.java from you command prompt and then after compilation, class file is created. You can run it using java MailClassName
You can find a good tutorial on using javac and java commands here.

How to run Java programs by clicking on their icon on Windows?

I have written a Java program that uses Java swing library. Now I would like to execute this program by double clicking on the executable file on Windows just like any other program with a GUI. How do I do that?

Since it is Java based and has a GUI, the obvious answer is to deploy it using Java Web Start.
Java Web Start (JWS) is the Oracle Corporation technology used to launch rich client (Swing, AWT, SWT) desktop applications directly from a network or internet link. It offers 'one click' installation for platforms that support Java.
JWS provides many appealing features including, but not limited to, splash screens, desktop integration, file associations, automatic update (including lazy downloads and programmatic control of updates), partitioning of natives & other resource downloads by platform, architecture or Java version, configuration of run-time environment (minimum J2SE version, run-time options, RAM etc.), easy management of common resources using extensions..
By 'desktop integration' read desktop shortcuts and menu items on supported platforms.
The 2 icons on the right (JotPad & Star Zoom Animation) are both Java based apps., installed using Java Web Start. Since JotPad is sand-boxed, the user will be prompted as to whether to create the shortcut. That choice is not offered for apps. with higher permission levels, so it would make more sense to install/remove the shortcuts and menu items using the IntegrationService - which allows an app. (after prompting the user) to create/remove them at run-time.

There are number of options:
Create an executable jar of your project. for this jar to work you have to have javaw as default application to open it.
Create an exe of your project.
Create a bat file which runs your jar file.
Take a look at this: How can I convert my Java program to an .exe file?

While the others mention excellent choices like creating a native executable, there is another useful method: creating a shortcut.
Right click your desktop, expand the "New" option, and click on "Shortcut".
Type "javaw.exe". Click next.
Name it whatever you want. Click done.
You'll notice the newly created shortcut on your desktop. Right click it and choose "Properties"
In the "Target" textfield, append "-jar path-to-your-jar.jar" where you replace "path-to-your-jar.jar" with the actual path to your jar
You can also now optionally change the icon to whatever icon you want
This shortcut can be pinned to the taskbar and be used from anywhere (considering you provided an absolute path to your JAR).

you need to create exe from the java program.
Creating executable jar files
First, make sure you have installed Java 1.2 or above. This facility is not available in previous versions of Java.
Next, create your working java system. In general, you will want to put it into a package. For this example, I created a trivial HelloWorld application that prints out "Hello World" plus the first command line argument, and placed it into the package "psae". Therefore, the HelloWorld files (HelloWorld.class, HelloWorld.java) were located in the directory psae. I tested the system to make sure it worked before going on to the next step.
In the directory in which the psae is located, created a file called "mainClass". This file contains a single line specifying where the main Class is to be found in the jar file. Note that I use the package specification. Here is the single line:
Main-Class: psae.HelloWorld
Note: make sure you type a carriage return after this line; some windows systems need it and will report a "Failed to load Main-Class manifest attribute" error.
Next, I create a jar file called psae.jar using the "jar" command in Java2. I use the "m" command line argument to specify the manifest file mainClass, which adds information to the jar file on where the main class will be found. Here is the jar command:
bertha:~ > jar cmf mainClass psae.jar psae
Just for fun, and to check what's happened, I print the table of contents for the jar file I just created. Here's the command and its result:
bertha:~ > jar tf psae.jar
META-INF/
META-INF/MANIFEST.MF
psae/
psae/HelloWorld.java
psae/HelloWorld.class
Having successfully created the jar file, I can now invoke java2 on it with the command line argument:
bertha:~ > java -jar psae.jar Philip
Hello World Philip

There are a few projects, like http://jsmooth.sourceforge.net/ and http://launch4j.sourceforge.net/

you can use something like Launch4j.
also look at JSMooth.
Hope it helps

There are two ways. Both involve packaging your code in a .jar.
The first way is to build an actual .exe file using a tool like Launch4j. It will require you to set up things like tell it which class to execute, which icon to use, which JRE is OK, what JRE parameters to use, etc.
The second option is to make the .jar itself executable. You do this by adding a manifest to the .jar. The manifest is a small configuration file that describes the jar. One of the attributes is Main-Class which defines the entry point. In other words, it says which class has the main function that should be called when the user double-clicks the file.
Here's a basic tutorial about manifests: http://docs.oracle.com/javase/tutorial/deployment/jar/manifestindex.html
The 2nd option is easier to get going, but users will know what to do with a .exe far more often.
Note that if either approach complains that it can't find the class, make sure to set the classpath manifest attribute to match your project.

If you have an executable jar file, just shift-right click on your file and set it to be opened by javaw. The other option (in case you want to pass in parameters to your application) is to create a .bat file where you spin off your application via java or javaw

Right click to your "project" in eclipse and select "export" then choose "Java->Runnable Jar File" select your project name and finish.

Seems you want to deploy and run the standalone application of swings. Being a java developer you should understand the power of jar files. Those are executable in themselves {so no need to create .exe files :)} .
The below code will help you to create a jar file.
Creating a jar File in Command Prompt
Start Command Prompt.
Navigate to the folder that holds your class files:
C:\>cd \mywork
Set path to include JDK’s bin. For example:
C:\mywork> path c:\Program Files\Java\jdk1.5.0_09\bin;%path%
Compile your class(es):
C:\mywork> javac *.java
Create a manifest file:
C:\mywork> echo Main-Class: NameOfProject >manifest.txt
Create a jar file:
C:\mywork> jar cvfm NameOfProject.jar manifest.txt *.class
Test your jar:
C:\mywork> DanceStudio.jar
After creating a jar just double click on it and you are done.

You have to create an executable jar file. For that you just simply add a META-INF folder to the jar, then add a MANIFEST.MF text file with two lines:
Manifest-Version: 1.0
Main-Class: your.package.YourMainClass

Here's how to run a Java program by RIGHT-CLICKING on it (in other words, from the Windows Explorer context menu). This handy trick is great for beginners who need to test their simple programs on the fly. Works on both Win7 and XP rigs.
[ATTN: Depending on the situation, you may need to remove the package directive from the top of your Java file.]
Step 1. Create a batch file (e.g., RWJ.bat) inside a folder of your choice (say, in C:\Program Files\Java.)
Step 2. Fill RWJ.bat with the following commands (they will work just fine as is with simple classes but you can, of course, tweak them according to your particular needs by specifying compiler / interpreter switches, passing args, adding echo off, removing pause or whatever):
javac %1
java %~n1
pause
The first command passes the full name of your right-clicked file to the Java compiler; the second one strips the file extension and feeds JVM with the class name only.
Step 3. Add the following key to your Registry: HKEY_CLASSES_ROOT\*\shell\Run With Java and then create its command (default value):
C:\Program Files\Java\RWJ.bat %1.
Step 4. Run your Java class by right-clicking it and selecting Run with Java option.
That's all there is to it.
Another way to run Java programs by pointing and clicking is to use AOT compilers. For example, GCC has an entry point named GCJ, which can be used to compile the source code into both byte codes and standard executable file for your particular OS.
And finally, instead ot batch files one can run WSH, etc.

Have the ability to set Java application as default file opener?

I've been searching for a way to have users set my program as the default to open files for awhile and found nothing. I have a program that is supposed to be universal for Mac, Windows and Linux, so I don't want to use a method that only works with one OS. So how can I give users the ability to set a Java app as the default file opener? Would I use the Desktop class?

No Java does not support this. You would have to write a small app for every OS that you want to support in its native language (c++, objective c, etc.) that would simply launch your java app whenever it is opened. You can then set that app as the default program.

It is answered here on stackoverflow:
Use a Java application as the Default Program for a particular file type?
Quote the answer:
JAR files are normally not executable. That is, a JAR file is not a valid Windows application. It doesn't matter if the JAR extension itself has a default application associated with it, because the "Open verb" is not used recursively in other "Open verb" definitions.
Instead,
Create a batch (".BAT") file (or small EXE wrapper) that calls java (or javaw, as appropriate) and use that executable wrapper as the "Open with" program. (This will have an annoying intermediate console window if using a batch file.) Or,
Modify the registry so that the "Open verb" for the extension launches the JAR through java (or javaw).
In the end, either form should look similar to: javaw -jar TheJarFile.jar "%1%". (Note that javaw is an executable, while TheJarFile.jar is not an executable.)
See java - the Java application launcher for how to use java/javaw.
That is the case for windows. Similarly on Linux and Mac you would have to make a native application wrapper that opens a file, and passes the file's path to your java jar as a parameter and runs the jar.

How to create an executable (a file that starts the program on double-click like an .exe) in JAVA with Eclipse?

I've created a program in java and now I want to create an executable from it.
I'm new to java, I don't know if it should be a .exe.
I'we exported my project to a .jar file, but when I double-click it it opens "open with" window.
I want to export my project to a file that runs my program on double-click.
Is there any solution?

Export --> Java --> Runnable Jar file --> Specify the class with static main method to run.
Double click on the Jar file to run..
Thanks...

Java compiliation creates byte code for the JVM, so a native, binary executable is not created during compiliation (like C or C++ programs). This is a feature of Java.
To deploy an application to multiple systems they must have the JRE. These .jar files can be launched from the command line (see this: http://download.oracle.com/javase/tutorial/deployment/jar/run.html)
Some vendors get around this with batch files that launch the JRE to run their application's JAR (and then put these in the start menu, desktop, etc with a fancy icon).
If you want people to install your app (especially from a web page or over a network) you probably want a Java Web Start package (see this for crating one in Eclipse: http://help.eclipse.org/indigo/index.jsp?topic=%2Forg.eclipse.platform.doc.isv%2Fguide%2Fjava_web_start.htm)

If you just want it to be runnable on your computer, you can use the open with dialog to open it with javaw.exe in JDK_DIRECTORY\bin. Alternatively, if you really wanted to make it an EXE, you could look at some of the answers here.

Either do as in the link mentioned by #dacwe or I would suggest to depending on operating system set a permanent connection between java and jars, then it will always happen.
On Windows you do it by right clicking on any jar then open with and find your javaw.exe in bin folder of your jre installation.

I think you are looking for a simpler approach than Java Web Start.
I assume that you are a Windows User, since you want a .exe file.
So once you have the exported MyProgram.jar file, you only need to create a .bat file
that contains a sole line:
java -jar MyProgram.jar
and place this execute.bat file in the same folder as your MyProgram.jar
This approach works for Linux too, only you need to place it inside a similar file and execute the same command.
Read here http://javabeanz.wordpress.com/2009/01/29/running-an-executable-jar-from-command-line/ for more explanations.