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How to Download Java and run a file on command line

I know this is SUPER basic. I am very new to all of this. I tried to download java and run a helloworld by following these instructions: https://docs.oracle.com/javase/tutorial/getStarted/cupojava/win32.html
I got an error when I tried to use the "javac" command to compile. This is what appears in the command prompt:
C:\Users\USer18\Desktop>javac HelloWorldApp.java
'javac' is not recognized as an internal or external command, operable program or batch file.
Does this mean I downloaded java incorrectly? When I downloaded it, there were 3 different things to choose from, but I could only choose one, so I chose the first one. I tried to download java again and select the second one, but it said it didn't work.
Thanks in advance for helping me!

From the tutorial you linked, it tells you to "consult the installation instructions" found here: https://docs.oracle.com/javase/8/docs/technotes/guides/install/install_overview.html
For Windows JDK, the instructions linked are here: https://docs.oracle.com/javase/8/docs/technotes/guides/install/windows_jdk_install.html#CHDEBCCJ
The part you need to look for is "Updating the PATH Environment Variable"
Updating the PATH Environment Variable
If you do not set the PATH variable, you need to specify the full path
to the executable file every time you run it, such as:
C:> "C:\Program Files\Java\jdk1.8.0\bin\javac" MyClass.java
It is useful to set the PATH variable permanently so it will persist
after rebooting.
To set the PATH variable permanently, add the full path of the
jdk1.8.0\bin directory to the PATH variable. Typically, this full path
looks something like C:\Program Files\Java\jdk1.8.0\bin. Set the PATH
variable as follows on Microsoft Windows:
Click Start, then Control Panel, then System.
Click Advanced, then Environment Variables.
Add the location of the bin folder of the JDK installation to the PATH variable in System Variables. The following is a typical value
for the PATH variable:
C:\WINDOWS\system32;C:\WINDOWS;C:\Program Files\Java\jdk1.8.0\bin
Note:
The PATH environment variable is a series of directories separated by semicolons (;) and is not case-sensitive. Microsoft Windows looks
for programs in the PATH directories in order, from left to right.
You should only have one bin directory for a JDK in the path at a time. Those following the first instance are ignored.
If you are not sure where to add the JDK path, append it.
The new path takes effect in each new command window you open after setting the PATH variable.

When ever we execute any command, it is searched in the directory where we are current in or mentioned in PATH environment variable. The oly thing which you need is just add <path of yourjdk>\bin to PATH
Windows 10 and Windows 8
In Search, search for and then select: System (Control Panel)
Click the Advanced system settings link.
Click Environment Variables. In the section System Variables, find the PATH environment variable and select it. Click Edit. If the PATH environment variable does not exist, click New.
In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.
In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.
Windows 7
From the desktop, right click the Computer icon.
Choose Properties from the context menu.
Click the Advanced system settings link.
Click the Advanced system settings link.
In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.
Reopen Command prompt window, and run your java code.

Ionic build failed; invalid %JAVA_HOME% (android)

I've searched around a bunch and could not find an answer that could help me.
I get this message when building my Ionic project for Android. I have verified, that both java -version and javac work in the folder, so both are accessible via the %path%.
What can I do to resolve this, and did I miss something?

I'm not familiar with Ionic but apparently it is not using %PATH% , it is using %JAVA_HOME%. You need to set it.
Determine the directory of a Java JDK (not JRE) in your system. It could be something like C:\Program Files\Java\jdk1.8.0_65. Since javac responds, you must have a JDK in the path somewhere. This directory will be the value for JAVA_HOME. (NOTE: This is not the same as the Java bin directory in the path! There should not be a bin on the end of the directory.)
Open the System page in your Control Panel.
You can do this in various ways:
Open an Explorer window, right-click on This PC and click on Properties in the menu.
Open Control Panel, click on System and Security, click on System.
Click on Advanced System Settings.
The System Properties window opens. Select the Advanced tab.
Click on the Environment Variables... button.
The Environment Variables window opens. Look at the bottom section labeled System Variables. You should see a variable named JAVA_HOME in the list. If you have this variable, double-check that the directory in the value exists and is a valid JDK directory.
If you don't see JAVA_HOME in the list, click the New... button. If JAVA_HOME is there but it's the wrong value, select JAVA_HOME in the list and click the Edit... button.
The New System Variable or Edit System Variable window will open (they look about the same.) Enter "JAVA_HOME" for variable name and the JDK directory for variable value. You can use the Browse Directory... button to make sure you have a valid directory for the value.
Click the Okay button on the New/Edit System Variable window, then the Environment Variables window, and then the System Properties window.
You will need to log out and log in again for the JAVA_HOME variable to take effect.

java compiler environment not working windows

Hi I have set the environment variable for java in windows.
when I type java in cmd, it works,but when I type javac ,it doesn't work saying javac' is not recognized as an internal or external command,
Doing Path="C:\Program Files\Java\jdk1.7.0_09\bin works but when I close the command prompt and reopen again same error.
Is there anyway out to set this permanently.

You can add C:\Program Files\Java\jdk1.7.0_09\bin to your path using the System Control Panel in Windows.
Go to Control Panel -> System -> Advanced System Settings -> Environment Variables...
Find Path, and edit it to add your jdk path.

It sounds like you simply setting the PATH variable of the current session. What you need to do it go to "Computer/My Computer", right click and select "Properties". From there click "Advanced System Settings" and then the "Environment Variables button. Navigate to the PATH variable and append to the end of the string. Directory paths must be separated by a semi-colon.
All of the variables in this section are loaded each time a new process is launched. You can also add a default CLASSPATH variable here and include all of your go-to jars.

Recently I have faced this problem and my finding is for Windows 7 adding javac to the "path" environment variable works but for windows 10, you can do anything means Add a new environment variable or update the existing one.

setting class path in Java

I used to run eclipse on my laptop. I have installed and used Secunia PSI application in order to update the apps, but once I done that I cannot run Eclipse.
This is what I have:
I set the PATH to the directory which contains javaw.exe app. The path at the PATH variable is the same as of CLASSPATH variable.
So, what are your resolutions? Done, it works now. I just simply needed to add '.;' at the end of the path link at the PATH.
Cheers

As the error message clearly states, Eclipse cannot find the entire JVM.
Add the directory that contains javaw.exe to your PATH.

Better to add JAVA_HOME as a new system variable in the same screen where you see the class path by clicking New and providing the folder location for JAVA root installation folder e.g. below:
Variable Name= JAVA_HOME
Variable Value= C:\Program Files\Java\jdk1.7.0_09

Starting with Java

So I am trying to start with Java (as in, trying to get the dang thing to accept code). I download all the needed things (the SDK) from Java and such, but when it gets to the point where I have to do "javac" in Command Prompt to compile the notepad file, I just get the message saying that there is no command called "javac".
Anybody wanna share some insight?

To set the environment variable PATH: http://www.java.com/en/download/help/path.xml.
Also I recommend using an IDE such as netbeans or eclipse. They make it much easier when starting off in java, plus when getting into advanced projects with many classes, they help greatly.

You need to set the path to your java compiler for it to be found when you use the command prompt. This page explains how.

I would suggest setting the following environment variable:,
JAVA_HOME to point to the root of your java installation e.g. C:\Program Files\Java
than append the following to your PATH environment variable:
;%JAVA_HOME%\bin
than you will be able to use java and javac from the command line.
Also see this article from Microsoft on setting environment variables if your not familiar with it.

You need to add the Java bin directory (where javac.exe is located, assuming you're on Windows), to your system PATH.
Right click on "My Computer", go to Environment Variables, and add the bin directory where Java is installed to your PATH variable.

You will need to have the java bin directory on your path. So, on windows, if installed at c:\java, and bin is c:\java\bin (normally you have version number, jre vs sdk, etc), you will need to add that to your PATH environment variable. set PATH=c:\java\bin;%PATH% -- you could do this in a setlocal/endlocal block or set it permanatly for your machine.
Also, the JRE may not have javac -- you may need to dowload the SDK.

Starting with java by typing 'javac' at the command line satisfy my mother's definition of the phrase 'starting with' ... as in,
"Don't start with me, buddy."
You are likely to end up with a punch in the nose.
For your own sanity, pick one of Eclipse, or NetBeans, or IntelliJ, or the other popular IDEs, and start from there.