Stuck Trying to Compile .Java - java

So I've been trying to figure out how to run .java files because I was trying to run someone's program and I've been researching solutions for sooo long
cd "directory with file trying to run"
set path=C:\Program Files\Java\my-java-version-or-whatever\bin
javac Test.java (<-- name of file)
also tried
SET JAVA_HOME
and that worked and showed a path but when I did javac again it still didn't work. All help is much appreciated!!
And for some reason it just keeps saying that javac is not recognized.

Please install JDK on your machine and point the JAVA_HOME to the same.
Find JDK Installation Directory
Open the default installation path for the JDK:
There should be a subdirectory like:
C:\Program Files\Java\jdk1.8.0_191
Set the JAVA_HOME Variable
Once you have the JDK installation path:
Right-click the My Computer icon on your desktop and select Properties.
Click the Advanced tab, then click the Environment Variables button.
Under System Variables, click New.
Enter the variable name as JAVA_HOME.
Enter the variable value as the installation path for the Java Development Kit.
Click OK.
Click Apply Changes.

If you have just set your JAVA_HOME make sure you restart your command console.

Related

Javac working with Powershell but not Command Prompt

I am trying to install Java in Windows 10 Home (64 bit). Like many tutorials point out, I downloaded the Java jdk setup file, executed it and once installed changed the Path in the Environment Variables. But for some reason, when I execute the command 'javac' it returns the not internal/external command error in Command Prompt but runs absolutely fine in Powershell. I tried to rectify this by uninstalling Java and reinstalling it very carefully, following all the steps but still this keeps on happening.
Also, during installation of Java, I lost the original value to my Path variable. Could this be causing the problem?
Edit : I was able to get the java command running in the command prompt but javac still won't work. I've already tried the methods suggested on other forums and this one but no luck so far.
See there is no problem with Java installation if you can find JDK(Java development kit) and JRE(Server Java runtime environment) in programme files in windows in a JAVA folder.
The main problem is with the environment variable declaration.
Go to environment variables and make a new path for that.
JAVA_HOME = "YOUR JDK & JRE INSTALLATION PATH"
And another one is
JAVA = "YOUR JDK & JRE INSTALLATION PATH"
Hope that help to you. After doing that if still there problem persisist just restart your PC and check again.
Just add your variable location up to /bin/
Refer to this :
https://www.windows-commandline.com/javac-not-recognized-internal-external-command/
Open file explorer
Right click computer then click properties
click advanced system settings
click environmental variables
click path (for me there was one in user variables for admin and another in system variables)
find the directory for javac (for me it was here C:\Program Files (x86)\Java\jdk1.8.0_191\bin)
so go back to file explorer and open program files x86
then open the java folder
then open the jdk folder
then open the bin folder
highlight the path in the search bar and copy it
click edit on path and paste into the path in the environmental variable for both(if you have more than one path)
If no path exists then create one in user variables
If there is any existing text place a semicolon ; between the text you pasted in there and the preexisting text.
close command prompt and reopen it.
type javac -version
the version info should be listed
This problem comes up with the directory of your command prompt.
check your PowerShell and command prompt default directory.
We can run command prompt as WinKey+R then type cmd, Hit the enter button then check our java version cmd javac -version.

Unable to find javac

I have been trying to get an automated system for the video game minecraft to work. I have to compile it myself, and after following the guide EXACTLY, I get this when running the build.xml with ANT. Below is the code and the error in it.
Buildfile: C:\Users\Arm\workspace\DarkBot\build.xml
init:
clean:
[delete] Deleting directory C:\Users\Arm\workspace\DarkBot\bin
compile:
[mkdir] Created dir: C:\Users\Arm\workspace\DarkBot\bin
BUILD FAILED
C:\Users\Arm\workspace\DarkBot\build.xml:21: Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK.
It is currently set to "C:\Program Files (x86)\jre1.8.0_25"
What am I doing wrong? Also I can assure that JAVA_HOME points to the correct area, as suggested in the error message.
JRE is not equal to JDK.
JRE stands for Java Runtime Environment, which is used to RUN Java programs.
JDK stands for Java Development Kit, which is used to COMPILE Java programs; it includes javac, the Java compiler.
Install JDK and points JAVA_HOME to correct location to resolve your issue.
Install JDK , JDK compiles your program and it has javac in bin folder like this "C:\Program Files\Java\jdk1.7.0_51\bin".
Set its path in Environment variables either in system variables "path" key or as "JAVA_HOME"
you can try Uninstalling and Re-installing already installed one.
All ant stuff will work fine except the javac task which needs the tools.jar, located in the /lib directory from the JDK, JRE is not sufficient in that case.
eclipse setting
Right Click build.xml ---> Build path ---> configure buildpath ---> select libraries tab
click "Add library" ---> double click on [jre system library ] ---> environments ---> installed jres ---> Add ---> standard vm
click on directory ---> Browse upto jdk [C:\Program Files\Java\jdk1.7.0_01]
finish
change the selection jre to jdk ---> click ok
If you can not find the path after testing on the command prompt and it says something like 'error java not found or it is not available from the internal or external .....' then follow the steps below:
Go to C:\Program Files\Java\jdk1.7.0_76\bin this shows the location of your java bin copy the path shown.
Go to Mycomputer > system properties > advanced settings> Click on Environmental Variables > (check this closesly... on the second section of the window where it says 'System Variables' scroll down the list till you find 'path' on the left)
click on the 'path' found from the list of system variables and click 'edit'.
Now paste your copied link in my case C:\Program Files\Java\jdk1.7.0_76\bin
Click Ok and go back to command prompt and test it. I hope this helps as mine is working now.

"The system cannot find the file C:\ProgramData\Oracle\Java\javapath\java.exe"

I am on JDK 8u25 on Windows 8, and I am experiencing a problem with my Java installation. I can run javac perfectly fine, but running java produces this error message:
The system cannot find the file C:\ProgramData\Oracle\Java\javapath\java.exe
How do I fix this?
I think the problem has to do with my environment variables.
The important variables, as I have set them, are:
JAVA_HOME – C:\Program Files\Java\jdk1.8.0_25
CLASSPATH – .;%JAVA_HOME%\lib
PATH – <other paths omitted>;%JAVA_HOME%\bin
And their expansions, as viewed with set in cmd, are:
JAVA_HOME – C:\Program Files\Java\jdk1.8.0_25
CLASSPATH – .;C:\Program Files\Java\jdk1.8.0_25\lib;%CLASSPATH%;
PATH – C:\ProgramData\Oracle\Java\javapath;C:\Program Files\Java\jdk1.6.0_45\bin;<other paths omitted>;C:\Program Files\Java\jdk1.8.0_25\bin
The full output of set can be viewed here.
I've got a similar problem I'm currently working on solving. I can't say this will solve your error since there may be issues with other software (which is my case with Eclipse Luna).
Java is using the path given in your PATH variable, which is,
C:\ProgramData\Oracle\Java\javapath
Go to this folder (ProgramData is hidden, so unhide it if necessary) and right click on the java.exe symlink. You'll see in the Target field where it's looking for java.exe. It may be pointing to the java.exe file from your previous jdk1.6.0_45 install. Either paste in new shortcuts here or change the PATH setting as others have mentioned.
I've found that the Java installer doesn't change the javapath or update the system path, at least when going from 1.8 to 1.7. In my case changing the shortcuts only led to a problem with Eclipse on startup.
EDIT:-----
After playing with javapath folder shortcuts it turns out you need symlinks, at least for Eclipse. See, Windows how to create directory symlink.
You don't need the /d switch for a file symlink,
mklink java.exe "C:\Program Files\Java\jdk1.8.0_20\bin\java.exe"
mklink javaw.exe "C:\Program Files\Java\jdk1.8.0_20\bin\javaw.exe"
mklink javaws.exe "C:\Program Files\Java\jdk1.8.0_20\bin\javaws.exe"
This now works for me.
Why Oracle did such a poor way to point to java is beyond me. We solved this problem by creating a new link to the JDK
mklink /d C:\ProgramData\Oracle\Java\javapath "C:\Program Files\Java\jdk1.8.0_40\bin\"
The same would work for a JRE if that is all that is required.
This replaces the old symlinks in C:\ProgramData\Oracle\Java\javapath (if they existed previously)
I had in PATH:
C:\ProgramData\Oracle\Java\javapath;C:\Program Files\Java\jdk1.8.0_92\bin;<others omitted>
I removed:
C:\ProgramData\Oracle\Java\javapath;
and that fixed the issue for me. java -version now gives details about the Java version, etc.
This will solve all problems relating to Java and environment variables:
Make your way to Windows' Environment Variables dialog.
Under System variables, select the variable named Path. Click Edit...
Remove the entry that looks like:
C:\ProgramData\Oracle\Java\javapath
Add the path of your JDK/JRE's bin folder.
Don't forget to set JAVA_HOME.
I got same error while running JAVA command. To resolve this, I moved the java path as the first entry in the path, and it resolved the issue. Please have look at this screenshot for reference:
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.
There are 2 versions of jdk in your PATH VARIABLE jdk1.6.0_45 and jdk1.8.0_25. Try removing the first one ie. jdk1.6.0_45 from the PATH
If you're on a corporate PC that's fairly restricted by group policy, this might work....
Assuming that
your Windows PATH includes C:\ProgramData\Oracle\Java\javapath
you have JDK installed to C:\Program Files\Java\jdk1.8.0_60\bin
Then create the following text file mklink.bat and put it on your desktop:
rem mklink.bat
mklink /d C:\ProgramData\Oracle\Java\javapath "C:\Program Files\Java\jdk1.8.0_60\bin"
pause
Now right-click it and choose "Run as Administrator". Provide admin credentials. The script should report success. Now you can compile or run Java.
This usually happens when you update the java,
the easiest way to solve this is to just uninstall the JDK & then reinstall it.
NOTE: This doesnt remove the path or classpath so no need to worry.
Uninstall all JDKs installed on your computer from the Java Control Panel
Search for C:\ProgramData\Oracle\Java and delete that directory and all files contained within. You can do this from the command line using rmdir /S C:\ProgramData\Oracle\Java
Then search for C:\ProgramData\Oracle and delete the oracle folder. You can do this using rmdir /S C:\ProgramData\Oracle
Now install JDK and set the path.
Run the program.You won't find the same problem anymore.
This problem exists when you upgrade from one version to another.because jdk is not automatically upgraded.
For the same you can change the environmental varibles.
In system variables look for the PATH and add the jdk bin location in the front of the string(not at the back).
Once you have done that check in CMD if "java" and "javac" works.
if it works, again go to system variables.
add "CLASSPATH" A the variable and set value " .
c:\Program Files\Java\jdk1.8.0_91\lib;"
There must be two or more PATH variables. Try merging all of them into one using semi-colon (;)
I got the same after installing java8 from a non-permissioned account.
To fix I simply reinstalled from admin user account.
This created the quoted directory with file links to java exes.
I had also similar problem where by I had to un-install JDK 1.8 and needed jdk 1.7.
What i did was removed the symbolic links from the javapath and then imported the shortcuts of java, javaw, javaws from the bin directory to the javapath folder. However, I found some permission issues in the enterprise laptop where by I did not have the privilege to modify/ update this directory. I had given appropriate permission from the administrator and there by resolved it.
c:\ProgramData\Java\javapath is used for symlinks. You can of course add the full path to your Java Path to %PATH%, but equally you can create a symlink to the path to the above location.
Open CMD as Administrator.
Type mklink java.exe (full path to your Java.exe)
eg
mklink java.exe "C:\Program Files\Java\jdk1.8.0_25\bin\java.exe"
Don't worry.
Just uninstall jdk as well as jdk updates
Before re installing jdk ,delete the oracle folder inside programData hidden folder in C:\
Then reinstall.
Set the following,
JAVA_HOME
CLASSPATH
PATH
JRE_HOME ( is optional)
Please remove "C:\ProgramData\Oracle\Java\javapath\java.exe" from the Path variable and add your jdk bin path. It will work.
In my case the I have removed the the above path and added my JDK path which is "C:\Program Files\Java\jdk1.8.0_221\bin"
For New version of Java JavaPath folder is located
64 bit OS
"C:\Program Files \Common Files\Oracle\Java\javapath\"
X86
"C:\Program Files(x86) \Common Files\Oracle\Java\javapath\"
This will solve all problems relating to Java and environment variables:
Make your way to Windows' Environment Variables dialog.
Under System variables, select the variable named Path. Click Edit...
Remove the entry that looks like:
C:\ProgramData\Oracle\Java\javapath
Add the path of your JDK/JRE's bin folder.
Don't forget to set JAVA_HOME.
This helped me.......:-)
For me it worked like this:
On your desktop go to Search->View advanced system settings->Environment Variables
Under System Variables look for path and click Edit.
Click on New and add the new Path and move it to the top.
To find your java path if you don't know where it is installed in cmd type where javac
<>\Common Files\Oracle\Java\javapath\ is now created as a junction, no symlinks anymore

mvn --version not working?

I have problem with MAVEN path
i have already set all the path but not working please see the below path
Path
....;C:\Program Files\Java\jdk1.6.0_20\bin;D:\apache-maven-3.2.1\bin
JAVA_HOME
C:\Program Files\Java\jdk1.6.0_20
MAVEN_HOME
D:\apache-maven-3.2.1
When i try to run mvn --version it will give error of JAVA_HOME please see the error
Error: JAVA_HOME is set to an invalid directory.
JAVA_HOME = "C:\Program Files\Java\jdk1.6.0_20\bin"
Please set the JAVA_HOME variable in your environment to match the
location of your Java installation.
But javac is working fine
JAVA_HOME needs to point to the folder which contains bin/, lib/, etc.
Your variable points inside of Java's home folder.
Change JAVA_HOME C:\Program Files\Java\jdk1.6.0_20\bin to C:\Program Files\Java\jdk1.6.0_20.
PATH and JAVA_HOME are two different things:
With PATH you tell the system where to search for commands. There you should have
PATH=...;C:\Program Files\Java\jdk1.6.0_20\bin;
With JAVA_HOME you define where your Java has been installed. Applications using JAVA_HOME add the bin and/or lib directories. There you should have
JAVA_HOME=C:\Program Files\Java\jdk1.6.0_20
Try the following in a DOS-Box:
set JAVA_HOME=C:\Program Files\Java\jdk1.6.0_20
set MAVEN_HOME=D:\apache-maven-3.2.1
set PATH=%JAVA_HOME%\bin;%MAVEN_HOME%\bin
mvn --version
Once you have identified the JRE installation path:
Right-click the My Computer icon on your desktop and select Properties.
Click the Advanced tab.
Click the Environment Variables button.
Under System Variables, click New.
Enter the variable name as JAVA_HOME.
Enter the variable value as the installation path for the Java Development Kit.
If your Java installation directory has a space in its path name, you should use the shortened path name (e.g. C:\Progra~1\Java\jre6) in the environment variable instead.
Icon
Note for Windows users on 64-bit systems
Progra~1 = 'Program Files'
Progra~2 = 'Program Files(x86)'
Click OK.
Click Apply Changes.
Close any command window which was open before you made these changes, and open a new command window. There is no way to reload environment variables from an active command prompt. If the changes do not take effect even after reopening the command window, restart Windows.
If you are running the Confluence EAR/WAR distribution, rather than the regular Confluence distribution, you may need to restart your application server.
You required to set or make sure about 3 variables environment behaviour:
1. M2_HOME: set this environment variable to point out to apache maven directory. Note: must not be point to bin directory.
JAVA_HOME: This environment variable must be point to jdk folder, not include bin directory.
path: your system/user path variable must be pointing to bin directory of java environment.
this works fine for me.
first set all these things
set JAVA_HOME=C:\Program Files\Java\jdk1.6.0_20
set MAVEN_HOME=D:\apache-maven-3.2.1
set PATH=%JAVA_HOME%\bin;%MAVEN_HOME%\bin
check
mvn --version
if still not working then delete path in environment variables again create it as
PATH=%JAVA_HOME%\bin;%MAVEN_HOME%\bin
close previously opened cmd prompt
open new cmd
and check
mvn --version

"java -version" not working in command prompt

I downloaded this Java JDK and installed it.
But when I go to the command prompt to check the version, it says it's not recognized.
Is anyone else experiencing this issue with the latest Java?
I might not have installed the right version. I need the java that works with grails
C:\>java
'java' is not recognized as an internal or external command,
operable program or batch file.
C:\>java -version
'java' is not recognized as an internal or external command,
operable program or batch file.
C:\>
when i do a search on my computer for java, it does not find anything
Windows 2k8 R2 server-
For both java [-option] or %JAVA_HOME% to work in the command line you need the following:
In Control Panel->System and Security->System->Advanced system setting->Advanced->Environment Variables->System Variables
Edit the Path variable and add a ";" after the last value and add the the path to the Java bin directory:
e.g.- C:\Progra~2\Java\jre6\bin\
Add the JAVA_HOME Variable with the value set to the path for the java executable:
e.g.- C:\Progra~2\Java\jre6\bin\java.exe
Press simultaneously the "windows" and "pause" buttons on your keyboard, this will bring up the System Preferences dialog.
In the Advanced tab, find Environment Variables.
Then, in the User (upper) section, create or update the following two variables :
JAVA_HOME = where you put your JDK, eg. C:/Java/SDK
PATH = %JAVA_HOME%/bin
Close the dialogs.
Then, in a new command-line console, try "javac -version" and see if it's detected.
It's important that you use a new console, because environment variables are read only when the console is launched.
Java is typically installed (on Windows) as C:\Program Files\Java\jdk<version>
That installation directory has a subdirectory bin which you need to append to your PATH environment variable via the control panel. Then, the commands like java, javac etc. will be available on the command line.
BTW, the same is true for Grails.
Is the -version flag not recognized, or is the "java" command not recognized? One way to test this is just to type 'java' by itself and run it and see what happens.
If the command is not recognized, make sure that the JDK's install path is in your windows PATH. If not, you won't be able to use any of the java executables from the command prompt. Here's another link that may help out.
You need to manually add the path to javac.exe and java.exe to your operating system path. The Java installation program doesn't do that for you.
You most likely don't have java.exe in your system's PATH variable.
For Linux:
check $PATH and $JAVA_HOME. You can configure it in /etc/environment
From console you can check it like:
$ echo $PATH
For Windows:
My Computer -> Properties -> Advanced -> Environment Variables
Check there PATH.
From console you can check it like:
echo %PATH%
You should have a Java icon in Windows Control Panel. Locate the Java tab and click the View button. That will show you the path to the Java executables.
Last but not least, make sure you have restarted the computer so changes in the PATH variable can take effect.
You installed the JDK. Isn't java.exe part of the JRE? Do you have that installed?
Maybe your system variables in the environment variables are not set properly. Follow the steps in the link below. Finally, make sure the path component in system variables has only one JDK path. Delete other JDK paths that you won't use.
https://docs.oracle.com/javase/tutorial/essential/environment/paths.html
You might have installed a previous or older version of Java so you can just uninstall it and directly download JDK from Java JDK
I was also facing the same issue but when I downloaded and installed the latest version the issue was resolved.
Also uninstall any other Java versions which may be present in the program files.
To get to know other versions which may be present in your computer use Windows File Explorer to go to:
Files > Windows C > Program Files > Java
All the JDK and JRE you have will be listed there. Uninstall any other Java versions other than what you installed. And then make sure you have set the path variable of the JDK.
For me, it was incorrect line in the PATH
(1) Check PATH: Type "Edit System Environment Variables" on the search -> System Properties -> Advance -> Environment Variables -> System variables -> Path
(2) On the list, mine was C:\Program Files (x86)\Common Files\Oracle\Java\javapath so I just add \ at the end (the exe files in the javapath folder)
OS: Windows 10 64 bit
IF you set the PATH and it's not showing up in cmd when you run %PATH%, try restarting your computer.

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