I have the JDK 10.0.2 installed, have the cmd opened in the folder of the class files of my program and try the command: javap Simulation.class .
I get the error that the command javap is not found. What do I do wrong?
You must have your $JAVA_HOME/bin directory added to system PATH for javap command to be available without it's absolute path.
Alternatively you can call javap using the absolute path:
/usr/lib/.../bin/javap Simulation.class
Assuming you are on Windows, check in your environment variable PATH whether path to Java executables is set.
Ex. If you have installed Java on path,say, C:\Program Files\Java\jdk-10
Then you have to add C:\Program Files\Java\jdk-10\bin to your PATH environment variable to be able to execute java commands from anywhere on command line.
References for Oracle Docs
https://docs.oracle.com/javase/10/install/installation-jdk-and-jre-microsoft-windows-platforms.htm#JSJIG-GUID-DAF345BA-B3E7-4CF2-B87A-B6662D691840
https://www.java.com/en/download/help/path.xml
On a sidenote, recommend you to move to Java 11 or 17 now that Java 10 is no longer supported. The above instructions would still remain same.
append $JAVA_HOME/bin to system $PATH variable. for example on linux
JAVA_HOME= "path of java installation on system"
export PATH = $JAVA_HOME/bin:$PATH
Open the control panel and type envir in search bar.
Click on edit the system environment variables.
Click on environment variables in the advanced system properties.
Click on path mentioned in user variables.
Edit the path, and click new and paste the path of java jdk.
In my system, the path is C:\Program Files\Java\jdk-17.0.2\bin, it could be different for your system.
Click ok, the problem must be solved now.
I try to set JAVA_HOME variable on an ubuntu server. I get the Java path with this command
which java
/usr/bin/java
I set the result in /etc/environment
JAVA_HOME="/usr/bin/java"
When I try to run a mvn command I get this error
Error: JAVA_HOME is not defined correctly.
We cannot execute /usr/bin/java/bin/java
You should not set JAVA_HOME to /usr/bin/java, because that's just a symbolic link to the java executable, which points to where the real executable is.
JAVA_HOME should point to the Java installation directory, and not to the java executable (or a link to the executable).
Find out where your Java installation directory is and then set JAVA_HOME to that directory (and not to the java executable). If you installed Java using Ubuntu's package management system, then the Java home directory is probably one of the subdirectories in /usr/lib/jvm.
Per the Oracle site:
export JAVA_HOME=jdk-install-location
export PATH=$JAVA_HOME/bin:$PATH
You can add these lines into your ~/.bash_profile (or ~/.bashrc), and then refresh using source ~/.bash_profile
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
I have setup the Java path and I tried to run ElasticSearch on Windows 7. But I'm getting this error:
"no java.exe found on C:\Program Files\Java\jdk1.7.0_17\bin\".
I can run java & javac, they work fine.
How do I solve this issue?
So, I've kept hitting this problem and the solution is twofold. Like Udit said your Java_Home path should not include the bin folder (the reason being that the elastic search bat file seems to add on the bin folder manually, so if you add it the path would be bin\bin)
The second thing to check for is spaces in your path. If Java is installed to C:\Program Files then use C:\Progra~1 and if it's in C:\Program Files (x86) then use C:\Progra~2.
This should mean your Java_Home is set to something like C:\Progra~1\Java\jre7
To Verify this works open a command prompt and type %Java_Home%\bin\java and press return, you should then see all the command line parameters for Java listed. If you get this far you should be able to just run elasticsearch.bat
JAVA_HOME is the environment variable that points to Java installation directory.
Example: If u have installed Java in 32 bit windows 7 operating system, it would have installed in
C:/Program Files/Java/jdkx.x.x
This path should be put as JAVA_HOME. Probably you have set the path till bin directory i.e. C:/Program Files/Java/jdkx.x.x/bin
that is why it cannot find the java.exe.
I have downloaded both Java jdk1.7.0_06 and Java jre7. and i added the following system variable JAVA_HOME C:\Program Files\Java\jdk1.7.0_06\bin to my windows 7. But when I type the following in the CMD command line on my windows 7 C:\activiti-5.10\activiti-5.10\setup>ant demo.start to run a demo application I got the following error in the command line '
"java.exe"' is not recognized as an internal or external command, operable program or batch file
So does anyone know how i can solve this problem ?
BR
If you look at the "ant.bat" file, you will see that it looks for the "java" command in the following way:
If the %JAVACMD% environment variable is set, then it uses that.
Otherwise, if the %JAVA_HOME% environment variable is set, it tries to use %JAVA_HOME%\bin\java.exe
Otherwise, it tries to use java.exe; i.e. it will look on your %PATH%.
In your case, you have %JAVA_HOME% set ... but set to the Java installation's "bin" directory, not to the root of the installation. So the Ant.bat script looks in the wrong place for java.exe.
Just set %JAVA_HOME% correctly, and it should work.
JAVA_HOME C:\Program Files\Java\jdk1.7.0_06
As you can see from the above, you do not need to have the Java "bin" directory on your %PATH% for Ant to work, but it is a good idea to set it anyway. That way you can run the Java commands simply from the command line.
The setting of %CLASSPATH% is not relevant to this problem. Indeed, unless the build.xml file is broken, Ant will ignore your %CLASSPATH% environment variable.
You need to put the file java.exe in your PATH variable but the JRE in JAVA_HOME
JAVA_HOME is the path of JDK root folder.eg: C:\Program Files\Java\jdk1.7.0_06 but path define C:\Program Files\Java\jdk1.7.0_06\bin
JAVA_HOME C:\Program Files\Java\jdk1.7.0_06
JRE_HOME C:\Program Files\Java\jre1.7.0_06
path = C:\Program Files\Java\jdk1.7.0_06\bin;C:\Program Files\Java\jre1.7.0_06\bin
Typically JAVA_HOME should be the parent directory of the "bin" folder.(jre or jdk)
In this case ant expects the java to be from the JDK.
try following in a cmd window
set JAVA_HOME=C:\Program Files\Java\jdk1.7.0_06
set path="%JAVA_HOME%/bin;%path%;
ant
(side note: adding java.exe to path is not a requirement for ant; it is a convenience thing for the user)
Just delete the following set of files from your %windir/System32 folder. Actually deleting java.exe is enough but for consistency sake just delete all the java related binaries.
java.exe
javaw.exe
javaws.exe
Actually oracle windows installer places a copy of these files into %windir/System32 folder (which I don't understand why) but looks like they are not needed (as they are available anyway under JDK folder where you install them).
I have tried all the various solutions posted in the SO and other forums as well but none of them worked for me. I have also set all the relevant environment variables (JAVA_PATH, CLASS_PATH etc) correctly as well. Finally this is the only solution that has worked for me.
Go to the \squirrel-sql-3.9.0>squirrel-sql.bat .open that squirrel-sql.bat in Notepad and comment out the existing logic which is
=======================================
if exist "%IZPACK_JAVA%\bin\javaw.exe" (
set LOCAL_JAVA=%IZPACK_JAVA%\bin\javaw.exe
) else (
set LOCAL_JAVA=javaw.exe
)
echo Using java: %LOCAL_JAVA%
=================================
and add the below logic
#echo off
set LOCAL_JAVA=C:\Program Files (x86)\Java\jre7\bin\javaw.exe
echo Using java: %LOCAL_JAVA%
================================
make sure you add the correct path of javax.exe while adding above logic set LOCAL_JAVA=
and start the .bat file from CMD ..that's it. It should work. It worked for me.
I started getting this error in Android Studio after I updated it to version "Electric Eel".
It happened because Android Studio has changed where they put their JRE:
it used to be C:\Program Files\Android\Android Studio\jre
but now it is C:\Program Files\Android\Android Studio\jbr
To fix:
updated my JAVA_HOME environment variable to point to the new java location (C:\Program Files\Android\Android Studio\jre)
and then restarted Android Studio, and now it is fixed.
I agree with the above explanation but if the problem still persists try setting:
CLASSPATH = C:\Program Files\Java\jdk1.7.0_06\bin