Determination and CLASSPATH installation in LINUX
Excuse for a silly question (I ask to treat with understanding, I in linux the beginner and replenish knowledge as required) but how to define CLASSPATH in LINUX and where it is set. I tried to execute a command
root#one: echo $CLASSPATH
but in reply gave out only blank line.
okay so in order to set the classpath
//to temporarly set the classpath use export CLASSPATH=someclass path
open your bashrc file in nano editor(default provided editor)
type nano ./.bashrc
and type the class as mentioned below
export PATH=${PATH}:/usr/java/jdk1.5.0_07/bin
version may differ of your java
heres a link that may help you
TRY THIS LINK
Related
I am a new Linux user and am looking to get the emscripten emcc command to work globally on Ubuntu.
This is my current configuration:
LLVM_ROOT = '/home/mpaccione/Projects/emsdk/upstream/bin'
BINARYEN_ROOT = '/home/mpaccione/Projects/emsdk/upstream'
EMSCRIPTEN_ROOT = '/home/mpaccione/Projects/emsdk/upstream/emscripten'
NODE_JS = '/home/mpaccione/Projects/emsdk/node/12.9.1_64bit/bin/node'
TEMP_DIR = '/tmp'
COMPILER_ENGINE = NODE_JS
JS_ENGINES = [NODE_JS]
If I am in /var/www/html/collision-detection-wasm/hello-world
... command 'emcc' not found.
I followed the install instructions but they did not work how I would expect. I need this to work globally or it's not of use.
How do I go about doing that on Ubuntu Linux?
In order to use emcc it needs to be in your $PATH.
To do this you can run source /path/to/emsdk/emsdk_env.sh in your terminal.
Or if you want to make it permanent you can add that same command to your startup scripts (e.g. $HOME/.bash_profile or $HOME/.bashrc).
This is documented at https://emscripten.org/docs/getting_started/downloads.html.
Hijacking #sbc100's answer to further clarify things to answer OP's question asked as a comment.
In order to use emcc one needs to set the PATH and other environment variables.
As it can be seen in the documentation, the command source ./emsdk_env.sh (or source /path/to/emsdk/emsdk_env.sh if you are not within the emsdk directory) does exactly that for the current terminal.
If you want this effect to be permanent, then do just as #sbc100's said. Just add it to, for example, to your bashrc file by inserting source /path/to/emsdk/emsdk_env.sh to a new line at the end. This will make the script run each time a terminal opens. This may be annoying to same as it outputs what was added to PATH and which environment variables were set.
Alternatively, one may also add the entries to the bashrc manually that the script kindly tells us about. For me, it meant inserting the following lines:
## Emscripten ########
export PATH="/home/dudly01/repos/github/emsdk:$PATH"
export PATH="/home/dudly01/repos/github/emsdk/upstream/emscripten:$PATH"
export PATH="/home/dudly01/repos/github/emsdk/node/14.18.2_64bit/bin:$PATH"
export EMSDK="/home/dudly01/repos/github/emsdk"
export EM_CONFIG="/home/dudly01/repos/github/emsdk/.emscripten"
export EMSDK_NODE="/home/dudly01/repos/github/emsdk/node/14.18.2_64bit/bin/node"
I would think, however, that these lines need to be adjusted as the project evolves.
I am trying to get mujoco_py running. When I do
import mujoco_py
I get this error:
Exception:
Missing path to your environment variable.
Current values LD_LIBRARY_PATH=
Please add following line to .bashrc:
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/jonah/.mujoco/mjpro150/bin
I have added the above line to both /etc/skel/.bashrc and ~/.bashrc. If I run
echo $LD_LIBRARY_PATH
I get
/home/jonah/.mujoco/mjpro150/bin/
My .mujoco folder includes mjkey.txt and the mjpro150 folder. I can run ./simulate successfully, so I have a feeling that this is some kind of mujoco_py specific bug.
Which program do you use to import mujoco?
I had a similar issue using mujoco_py with PyCharm Community 2018.1. A workaround was to launch PyCharm from the terminal instead of using the launcher icon. Maybe it could help with your issue too.
Otherwise you could try adding the LD_LIBRARY_PATH to ~/.profile instead of ~/.bashrc, as proposed in this answer here: https://askubuntu.com/questions/1022836/python-not-recognizing-ld-library-path/1022913#1022913
You can try to reinstall Pycharm for the newest version.
After you save the .bashrc file your want execute this code.
source ~/.bashrc
Now link is updated.
Please check the user which you run the code with. The mismatch user will cause this problem. There is the checklist may help you:
Don’t use ‘sudo’ to run the code;
Don’t use ‘sudo’ or virtual environment (e.g., anaconda) to run Pycharm (If you run the code in Pycharm).
I am installing Apache Spark on linux. I already have Java, Scala and Spark downloaded and they are all in the Downloads folder inside the Home folder with the path /home/alex/Downloads/X where X=scala, java, spark, literally that's what the folders are called.
I got scala to work but when I try to run spark by typing ./bin/spark-shell it says:
/home/alex/Downloads/spark/bin/saprk-class: line 100: /usr/bin/java/bin/java: Not a directory
I have already included the file path by editing the bashrc with sudo gedit ~/.bashrc:
# JAVA
export JAVA_HOME=/home/alex/Downloads/java
export PATH=$PATH:$JAVA_HOME/bin
# scala
export SCALA_HOME=/home/alex/Downloads/scala
export PATH=$PATH:$SCALA_HOME/bin
# spark
export SPARK_HOME=/home/alex/Downloads/spark
export PATH=$PATH:$SPARK_HOME/bin
When I try to type sbt/sbt package in the spark folder it say no such file or directory is found also. What should I do from here?
It seems you have a few issues, namely your JAVA_HOME is not pointed to a directory with java, when you are running sbt in spark you should run ./sbt/sbt (or in new versions ./build/sbt). While you can download Java & Scala by hand, you may find that your system packages are sufficient (make sure to get jdk 7 or later).
Furthermore, after using system packages as Holden points out, in Linux you may use the command whereis to make sure of the right paths.
Finally, the following link may prove useful:
http://www.tutorialspoint.com/apache_spark/apache_spark_installation.htm
Hope this helps.
Note: It looks like there may be a configuration issue, misspelling, of the directory name
/home/alex/Downloads/spark/bin/saprk-class: line 100: /usr/bin/java/bin/java: Not a directory
saprk-class
That could be a configuration issue only, but it's worth a look if it is called /spark-class elsewhere to see if it's causing related issues.
I'm running IntelliJ Idea under linux. I have created a project and a module inside it, and in that module I have a class (MyClass.class) and when I'm trying to run it from IDE, I get
ERROR: MyClass.class (No Such file or directory)
Can somebody explain me why IntelliJ Idea doesn't recognize the classes inside my module? I know it should be a problem regarding module settings but I can't figure it out. I'm using Ubuntu 11.10
OK I place here the paths and everything for all to see :)
type : echo $PATH
Result:
/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/lib/jvm/java-7-openjdk-i386/bin:/usr/lib/jvm/java-7-openjdk-i386/bin:/usr/lib/jvm/java-7-openjdk-i386/bin
type: echo $JAVA_HOME
Result:
/usr/lib/jvm/java-7-openjdk-i386
type: ./idea.sh
Result:
NOTE: If you have both Sun JDK and OpenJDK installed
please validate either IDEA_JDK or JDK_HOME environment variable points to valid Sun JDK installation
Arkde, I have a possible explanation why Jaroslav's solution with JDK7 didn't work for you.
Maybe you had mixed Java versions in various alternatives items, possibly conflicting with the version that environment variables like JAVA_HOME and JDK_HOME point to?
Maybe something points to the /usr/lib/jvm/default-java symlink as the JDK home, and that symlink points to a different version of JDK than intended?
Did you try resetting alternatives for all Java tools to version 7? Like this:
update-java-alternatives --list
# ...see what JDK's are available, choose the one that corresponds to Java 7
# and set it to be the default in alternatives:
sudo update-java-alternatives --set java-1.7.0-openjdk-amd64
# or interactively:
sudo update-alternatives --config java
What do the following commands output on your system?
echo $JAVA_HOME
echo $JDK_HOME
ls -l /usr/lib/jvm/default-java
update-java-alternatives --list
update-alternatives --list java
I had exactly the same problem.
I've performed strace on the Idea process and in the log I saw it trying to open several .class files without the path to them specified - like open("SomeClass.class", O_RDONLY) = -1 ENOENT (No such file or directory) - no path to the project output directory and to appropriate package.
So I've apt-get installed JDK 7 along JDK 6:
apt-get install openjdk-7-doc openjdk-7-jdk openjdk-7-jre openjdk-7-jre-headless openjdk-7-jre-lib openjdk-7-source
In Ubuntu 11.10 Oneiric, OpenJDK 6 isn't removable if you want OpenJDK 7. JDK 7 is dependent on JDK 6...
So I've:
updated alternatives configuration as specified above,
changed the /usr/lib/jvm/default-java symlink to point to java-7-openjdk-amd64 ,
double checked all the environment variables (my JAVA_HOME and JDK_HOME both point to /usr/lib/jvm/default-java),
reconfigured my project's SDK appropriately (and for all the modules in the project),
and voila - problem solved!
Solved it. Remove all jdk/jre you have, install openjdk7.
Add this line to .bashrc
export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-i386/
export PATH=$PATH:$JAVA_HOME/bin
Run Idea. Profit. :)
I experienced the same problem. What I found is that the underlying system-wide Java version doesn't matter, so there is no need to set JAVA_HOME or update_alternatives. All I had to do was change some settings in IDEA:
Add a Java SDK, either OpenJDK 7, or Oracle JDK 6 or 7 (File -> Project structure -> SDKs)
Select it as Project SDK (File -> Project structure -> Project)
Check that Make checkbox is enabled, otherwise IDEA will not compile your project, also verify that class file is available in the output directory and you are running with the classpath of the correct module.
If the problem remains, send a sample project to support.
I've run into the same problem - I moved my projects (and Idea settings) from a laptop with Ubuntu 10.04 and sun-jdk-6 to a PC with Ubunty 11.10 and openjdk-6. Upon project rebuild I got MyClass.class (No Such file or directory) errors for ALL classes.
Thanks to Jaroslav, his (almost) solution did helped - I can't explain why, perhaps it would work with sun-jdk-6 too... So, I installed openjdk-7, without removing openjdk-6, and set 7th as a project's JDK in Idea. (I did not change anything in environment variables.) With jdk7 it compiled.
PS I should've written it as a comment to Jaroslav's post, not a separate answer, but I don't yet have enough reputation to do this...
Try to run IDEA using
sh -c "export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-i386 && ./idea.sh"
When it starts press Ctrl+Alt+Shift+S to open Project Settings dialog. In the left panel choose Project and verify that Project SDK is configured correctly (at least it is not red).
I downloaded apache-log4j-1.2.16.zip and unziped it. I then renamed it as LOG4J_HOME and placed it in /home/appnetix folder which is my folder. I tried setting the classpath in the terminal using the following command :
[appnetix#Sanjeev ~]$ set classpath=%path%;LOG4J_HOME/log4j-1.2.16.jar;
That returned:
bash: LOG4J_HOME/log4j-1.2.16.jar: Permission denied
I tried doing this:
[appnetix#Sanjeev ~]$ set classpath=%path%;//home/appnetix/LOG4J_HOME/log4j-1.2.16.jar;
But I got this:
bash: //home/appnetix/LOG4J_HOME/log4j-1.2.16.jar: Permission denied
Please help, I'm new in Linux (one month).
export CLASSPATH=/home/appnetix/LOG4J_HOME/log4j-1.2.16.jar
or, if you already have some classpath set
export CLASSPATH=$CLASSPATH:/home/appnetix/LOG4J_HOME/log4j-1.2.16.jar
and, if also you want to include current directory
export CLASSPATH=$CLASSPATH:/home/appnetix/LOG4J_HOME/log4j-1.2.16.jar:.
You have to use ':' colon instead of ';' semicolon.
As it stands now you try to execute the jar file which has not the execute bit set, hence the Permission denied.
And the variable must be CLASSPATH not classpath.
Can you provide some more details like which linux you are using?
Are you loged in as root?
On linux you have to run export CLASSPATH = %path%;LOG4J_HOME/og4j-1.2.16.jar
If you want it permanent then you can add above lines in ~/.bashrc file.