Develop Reference

How do I setup VSCODE to create Maven projects?

I recently installed Visual Studio Code and am now trying to create a Maven project. When I first tried to create a Maven project, I received an error about the JAVA_HOME setting, so I fixed that. Next I received an error saying it couldn't find an executable or script file in the Maven > Executable: Path folder. I disabled the setting named Maven > Executable: Prefer Maven Wrapper, and then I changed found the mvnw.cmd file and added the path to that folder to my settings (shown below):
C:\Users\user1\.vscode\extensions\vscjava.vscode-maven-0.21.4\resources\maven-wrapper
Now when I try to create the Maven project, I just get the following in TERMINAL window and no project is created:
>> cd "c:\Users\user1\Documents\Bidi\Source\Maven"
>> & "C:\Users\user1\.vscode\extensions\vscjava.vscode-maven-0.21.4\resources\maven-wrapper\" org.apache.maven.plugins:maven-archetype-plugin:3.1.2:generate -DarchetypeArtifactId="maven-archetype-quickstart" -DarchetypeGroupId="org.apache.maven.archetypes" -DarchetypeVersion="1.4"
>> "
Has anyone seen this problem and figured out how to fix it?

I was finally able to resolve the issue. After looking at Microsoft's troubleshooting page on GitHub here (https://github.com/microsoft/vscode-maven/blob/master/Troubleshooting.md), I searched for folders containing "apache-maven". I was then able to find the folder with the mvn file. I then entered the full path, including the file name in the maven.executable.path property and it worked. The full path was like this:
C:\Users\user1\.m2\wrapper\dists\apache-maven-3.6.3-bin\abc123abc123abc123XX\apache-maven-3.6.3\bin\mvn

Step 1 - Verify Java Installation on your Machine
Open console and execute the following java command.
OS Task Command
-Windows Open Command Console c:> java -version
-Linux Open Command Terminal $ java -version
-Mac Open Terminal machine:~ joseph$ java -version
Let's verify the output for all the operating systems −
If you do not have Java installed, install the Java Software Development Kit (SDK) from https://www.oracle.com/technetwork/java/javase/downloads/index.html. We are assuming Java 1.7.0.60 as installed version for this tutorial.
Step 2 - Set JAVA Environment
Set the JAVA_HOME environment variable to point to the base directory location where Java is installed on your machine. For example −
OS Output
Windows Set the environment variable JAVA_HOME to C:\Program Files\Java\jdk1.7.0_60
Linux export JAVA_HOME=/usr/local/java-current
Mac export JAVA_HOME=/Library/Java/Home
Append Java compiler location to System Path.
Verify Java Installation using java -version command as explained above.
Step 3 - Download Maven Archive
Download Maven 2.2.1 from https://maven.apache.org/download.cgi.
OS Archive name
Windows apache-maven-3.3.1-bin.zip
Linux apache-maven-3.3.1-bin.tar.gz
Step 4 - Extract the Maven Archive
Extract the archive, to the directory you wish to install Maven 3.3.1. The subdirectory apache-maven-3.3.1 will be created from the archive.
OS Location (can be different based on your installation)
Windows C:\Program Files\Apache Software Foundation\apache-maven-3.3.1
Linux /usr/local/apache-maven
Step 5 - Set Maven Environment Variables
Add M2_HOME, M2, MAVEN_OPTS to environment variables.
OS Output
Windows
Set the environment variables using system properties.
M2_HOME=C:\Program Files\Apache Software Foundation\apache-maven-3.3.1 M2=%M2_HOME%\bin MAVEN_OPTS=-Xms256m -Xmx512m
Linux
Open command terminal and set environment variables.
export M2_HOME=/usr/local/apache-maven/apache-maven-3.3.1 export M2=$M2_HOME/bin
export MAVEN_OPTS=-Xms256m -Xmx512m
export M2=$M2_HOME/bin
export MAVEN_OPTS=-Xms256m -Xmx512m
Step 6 - Add Maven bin Directory Location to System Path
Now append M2 variable to System Path.
OS Output
Windows Append the string ;%M2% to the end of the system variable, Path.
Linux export PATH=$M2:$PATH
Mac export PATH=$M2:$PATH
Step 7 - Verify Maven Installation
Now open console and execute the following mvn command.
OS Task Command
Windows Open Command Console c:> mvn --version
Linux Open Command Terminal $ mvn --version
Finally, verify the output of the above commands, which should be as follows −

Where to install JDK .tar.gz file on Ubuntu 18.04?

Where is the recommended place to install the jdk .tar.gz file I just downloaded? I want it to be available for all users.
The installation guides that I have found told me to extract the jdk in many different places, such as /opt, /usr/lib and /usr/local. But the which one is the "right" choice? Why?

Into /usr/lib/jvm/ folder, the reason is because the default installation path is that one when you use the sudo apt install command, which makes total sense to me.
Example:
OpenJDK 11 is located at : /usr/lib/jvm/java-11-openjdk-amd64/bin/java
OpenJDK 8 is located at : /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java
For more information, you can read this article here.

First Download the Oracle JDK Download Oracle JDK or Open JdkDownload Open JDK, then follow these commands :
First Unzip the tar file with this following command
tar zxvf <tar file name>
Like : tar zxvf jdk-11.0.2.jdk
enter your password if asked
Now set the JAVA_HOME i.e system variables to the end of /etc/profile file
first, open /etc/profile : vi /etc/profile
and press I to insert and put this at the end
export JAVA_HOME=<Directory where JAVA has been extracted>
export JAVA_HOME=/home/jdk-10.0.2.jdk/Contents/Home
export PATH=$PATH:$JAVA_HOME/bin
now press ESC + SHIFT + :WQ to save the changes

For installation from the JDK tar.gz use the following command to unpack the tarball to the desired directory where you need to install java :
tar zxvf jre-8u73-linux-x64.tar.gz
Then you can set the java home by editing the environment file and set java home like :
JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64"
where the latter part is the directory in which you have installed java.Usually java will be installed in the /usr/lib/ .Use an editor like nano or vim to edit the file and add the above key value to set java home.

Error: JAVA_HOME is set to an invalid directory: /usr/lib/jvm/java-8-oracle/jre/bin/java when i run gradle command in terminal

I am working in Ubuntu 16.04. I need to install gradle and the gradle is installed when i checked with sudo apt list --installed command but when i use gradle -version command it shows the following error,
JAVA_HOME is set to an invalid directory: /usr/lib/jvm/java-8-oracle/jre/bin/java
In sudo vim /etc/environment file,
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"
JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64/"
http_proxy="http://username:password#IP:port no/"
https_proxy="https://IP:port no/"
ftp_proxy="ftp://IP:port no/"
I don't know where i made mistakes. Please help me.
Thanks.

On a 64bit openSuse 64 42.1 box;
readlink -f $(which java)
provided;
/usr/lib64/jvm/java-1.8.0-openjdk-1.8.0/jre/bin/java
But;
export JAVA_HOME=/usr/lib64/jvm/jre-1.8.0-openjdk
is the path that worked and allowed java emulator to run.
So i think we have to manually browse our file system and see what path to choose.

Today I faced this problem. I am using the default java that comes with your linux distro (so in my case, linux mint).
$ whereis java
This command gave me
java: /usr/bin/java /usr/share/java
So, I opened /user/bin. There was a link to Java. I right clicked it and selected follow original link. This lead me to /usr/lib/jvm/java-11-openjdk-amd64/bin/java.
So now that I know where this java is, I opened my .bashrc file, and edited the JAVA_HOME.
So for my case,
## My Custom variables
export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
export PATH=$JAVA_HOME/bin:$PATH
This solved the problem.
Now if you are using some other java (say you downloaded from oracle and extracted the zip file ...), then you have to add that location. So for example, if your java is in /home/user/.sdkman/candidates/java/current, then
export JAVA_HOME=/home/user/.sdkman/candidates/java/current
export PATH=$JAVA_HOME/bin:$PATH

I see a mismatch. In your enviornment file the JAVA_HOME is set to "/usr/lib/jvm/java-8-openjdk-amd64/" and your mentioned that the error that you got relates to the JAVA_HOME as "/usr/lib/jvm/java-8-oracle/jre/bin/java"
If you JAVA is really installed in /usr/lib/jvm/java-8-oracle directory, then you need to ensure that the JAVA_HOME is set to that directory. And also your PATH reflects $JAVA_HOME/bin in it.
I typically install Oracle JDK/JRE separately in a separate directory such as /usr/local/jdk1.8.0 etc.

check the jvm installtion folder from Files
eg : /usr/lib/jvm/java-12-oracle
then in terminal run sudo nano /etc/environment and add the line
JAVA_HOME="/usr/lib/jvm/java-12-oracle"
Then open terminal and run
export JAVA_HOME="/usr/lib/jvm/java-12-oracle"

Oracle SqlDeveloper JDK path

I have recently installed sqldeveloper but i'm getting the below warning window when I try to launch it. This is causing the sqldeveloper to run very very slow and it hangs frequently
I have tried editing the file sqldeveloper.cong as suggested in the window above but does not work
Original
SetJavaHome ../../jdk
Update 1
SetJavaHome C:\Program Files\Java\jdk1.7.0_60\bin\ and all other variations but still getting the above warning window
Update 2
SetJavaHome C:\Program Files (x86)\Java\jre7\bin and all other variations
Please suggest the correct way

The message seems to be out of date. In version 4 that setting exists in two files, and you need to change it in the other one, which is:
%APPDATA%\sqldeveloper\1.0.0.0.0\product.conf
Which you might need to expand to your actual APPDATA, which will be something like C:\Users\cprasad\AppData\Roaming. In that file you will see the SetJavaHome is currently going to be set to the path to your Java 1.8 location, so change that as you did in the sqldeveloper.conf:
SetJavaHome C:\Program Files\Java\jdk1.7.0_60\bin\
If the settig is blank (in both files, I think) then it should prompt you to pick the JDK location when you launch it, if you prefer.

another thing you could try is to rename your old jdk folder, lets say its:
C:\Program Files\Java\jdk1.7.0_04
change it to saomething like:
C:\Program Files\Java\xxxjdk1.7.0_04
Now, you should once again asked to set your jdk folder location on Oracle SqlDeveloper launch, and you can chose the right path.
Not the most elegant solution, but it worked for me.
Milos

In your SQL Developer Bin Folder find
\sqldeveloper\bin\sqldeveloper.conf
It should be
SetJavaHome \path\to\jdk
You said it was ../../jdk originally so you could ultimatey do 1 of two things:
SetJavaHome C:\Program Files\Java\jdk1.7.0_60
This is assuming that you have JDK 1.7.60 installed in that directory; you don't want to point it to the bin folder you want the whole JDK folder.
OR
The second thing you can do is find the jdk folder in the sqldeveloper folder for me its sqldeveloper\jdk and copy and paste the contents from C:\Program Files\Java\jdk1.7.0_60. You then have to revert your change to read
SetJavaHome ../../jdk
in your sqldeveloper.conf
If all else fails you can always redownload the sqldeveloper that already contains the jdk7 all zipped up and ready for you to run at will: Download SQL Developer The file I talk about is called Windows 64-bit - zip file includes the JDK 7

I cannot believe Oracle's documentation is SO LAME! In some documents it is misleading people to point to the JDK by specifying the path to the JDK root, e.g. on a Mac:
/Library/Java/JavaVirtualMachines/jdk1.8.0_151.jdk/
Reviewing /Applications/SQLDeveloper.app/Contents/MacOS/sqldeveloper.sh
revealed the method they use to set up the path:
TMP_PATH=/usr/libexec/java_home -F -v 9
if [ -z "$TMP_PATH" ] ; then
TMP_PATH=/usr/libexec/java_home -F -v 1.8
if [ -z "$TMP_PATH" ] ; then
osascript -e 'tell app "System Events" to display dialog "SQL Developer requires a minimum of Java 8. \nJava 8 can be downloaded from:\n http://www.oracle.com/technetwork/java/javase/downloads/"'
exit 1
fi
fi
Executing this manually from Terminal:
/usr/libexec/java_home -F -v 1.8
Lists the path as:
/Library/Java/JavaVirtualMachines/jdk1.8.0_152.jdk/Contents/Home
And this is what you need to specify as the value for
SetJavaHome /Library/Java/JavaVirtualMachines/jdk1.8.0_152.jdk/Contents/Home
Thank you Oracle for wasting half a day on your "product" that does NOT even support your latest Java version, also released by you.

On Windows,Close all the SQL Developer windows. Then You need to completely delete the SQL Developer and sqldeveloper folders located in user/AppData/Roaming. Finally, run the program, you will be prompted for new JDK.
Note that AppData is a hidden folder.

For those who use Mac, edit this file:
/Applications/SQLDeveloper.app/Contents/MacOS/sqldeveloper.sh
Mine had:
export JAVA_HOME=`/usr/libexec/java_home -v 1.7`
and I changed it to 1.8 and it stopped complaining about java version.

if you use sqldeveloper 18.2.0
edit %APPDATA%\sqldeveloper\18.2.0\product.conf
jdk9, jdk10, and jdk11 are not supported
change back to jdk 8
for example
SetJavaHome C:\Program Files\ojdkbuild\java-1.8.0-openjdk-1.8.0.191-1

How to set JAVA_HOME environment variable on Mac OS X 10.9?

I just purchased a brand new MacBook Pro.
This is my first MAC ever and I'm still trying to get the hang of navigating my way around.
Anyway, I'm also new to Java and I've been practicing on my Windows PC before it permanently died.
Now that I'm on this MAC, I installed my JDK and now I need to set the JAVA_HOME environment variable.
I have no idea what to do.
I tried following some of these guides and didn't get very far.
Mkyong.com : How to set JAVA_HOME variable in Mac OSX
YouTube : How to set environment variables on mac, linux, solaris, rhel
YouTube : How to Set Environment Variables in Mac
I was able to locate the terminal and I think I created some multiple files. I'm getting messages like this:
(1) Another program may be editing the same file.
If this is the case, be careful not to end up with two
different instances of the same file when making changes.
Quit, or continue with caution.
(2) An edit session for this file crashed.
If this is the case, use ":recover" or "vim -r /Users/Erwin/.bash_profile"
to recover the changes (see ":help recovery").
If you did this already, delete the swap file "/Users/Erwin/.bash_profile.sw p"
to avoid this message.
Can somebody tell how to set Java in Mac OSX environment step by step?

If you're using bash, all you have to do is:
echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.bash_profile
If you're using zsh (which probably means you're running macOS Catalina or newer), then it should instead be:
echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.zshrc
In either case, restart your shell.
If you have multiple JDK versions installed and you want it to be a specific one, you can use the -v flag to java_home like so:
echo export "JAVA_HOME=\$(/usr/libexec/java_home -v 1.7)" >> ~/.bash_profile

I just spent 2 hours setting this variable. The other answers did not work properly for me. I'm using macOS Catalina 10.15.4.
First, find your actual Java SDK Home directory:
/usr/libexec/java_home
Manually navigate there to make sure you don't have any mistakes due to incorrect versions, etc. For me, this was:
/Library/Java/JavaVirtualMachines/jdk-13.0.2.jdk/Contents/Home
Next, edit your terminal's profile. If you're using zsh, this will be:
vim ~/.zshrc
If you're not using zsh, this will be:
vim ~/.bash_profile
Inside, add the following new line anywhere in the file:
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-13.0.2.jdk/Contents/Home
Restart your terminal app (or source ~/.bash_profile), and it should work properly.

I did it by putting
export JAVA_HOME=`/usr/libexec/java_home`
(backtics) in my .bashrc. See my comment on Adrian's answer.

Set $JAVA_HOME environment variable on latest or older Mac OSX.
Download & Install install JDK
First, install JDK
Open terminal check java version
$ java -version
Set JAVA_HOME environment variable
Open .zprofile file
$ open -t .zprofile
Or create . zprofile file
$ open -t .zprofile
write in .zprofile
export JAVA_HOME=$(/usr/libexec/java_home)
Save .zprofile and close the bash file & then write in the terminal for work perfectly.
$ source .zprofile
Setup test in terminal
$ echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/jdk-13.0.1.jdk/Contents/Home

In Mac OSX 10.5 or later, Apple recommends to set the $JAVA_HOME variable to /usr/libexec/java_home, just export $JAVA_HOME in file ~/. bash_profile or ~/.profile.
Open the terminal and run the below command.
$ vim .bash_profile
export JAVA_HOME=$(/usr/libexec/java_home)
save and exit from vim editor, then run the source command on .bash_profile
$ source .bash_profile
$ echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home

It is recommended to check default terminal shell before set JAVA_HOME environment variable, via following commands:
$ echo $SHELL
/bin/bash
If your default terminal is /bin/bash (Bash), then you should use #Adrian Petrescu method.
If your default terminal is /bin/zsh (Z Shell), then you should set these environment variable in ~/.zshenv file with following contents:
export JAVA_HOME="$(/usr/libexec/java_home)"
Similarly, any other terminal type not mentioned above, you should set environment variable in its respective terminal env file.

If you are using Zsh, then try to add this line in ~/.zshrc file & restart terminal.
export JAVA_HOME=$(/usr/libexec/java_home)

I got it working by adding to ~/.profile. Somehow after updating to El Capitan beta, it didnt work even though JAVA_HOME was defined in .bash_profile.
If there are any El Capitan beta users, try adding to .profile

Since I'm using openjdk managed with sdkman, I added
sudo ln -sfn /path/to/my/installed/jdk/openjdk.jdk /Library/Java/JavaVirtualMachines/openjdk.jdk
Adding this to your system lets java_home recognize your installed version of Java even when its not installed via standard packages

I checked my /Library/Java/JavaVirtualMachines/
directory and found the version to be jdk1.8.0_321.jdk/Contents/Home
and added this directly to my .bash_profile:
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_321.jdk/Contents/Home
but it's still complaining after sourcing the .bash_profile:The operation couldn’t be completed. Unable to locate a Java Runtime that supports apt.

In the latest Mac, you have to add the Set $JAVA_HOME environment variable in .zprofile. Here, we simple way to open it. Press ⌘ + Shift + . from keyboard. Just open it and add the $JAVA_HOME environment variable as explained here:

JAVA 11 via Homebrew - tested on macos Ventura 2022
.zshrc
export JAVA_HOME=/opt/homebrew/opt/openjdk#11/libexec/openjdk.jdk/Contents/Home

For Mac M1
Download & Install install JDK
Open terminal check java version
java -version
Now create a file
touch .zprofile
Open the file
open -t .zprofile
Add the below line
export JAVA_HOME=$(/usr/libexec/java_home)

I resolved it on macOS Monterey by using the option provided by Google
Under Gradle JDK, choose the Embedded JDK option.
https://developer.android.com/studio/intro/studio-config#:~:text=A%20copy%20of%20the%20latest,use%20for%20your%20Android%20projects.

I'm able to solve this issue by setting JAVA_HOME in .bash_profile file
export JAVA_HOME=/usr/local/opt/openjdk#17
Note:
I installed openjdk version 17 using 'brew'. I got this location from brew console. I'm using 'bash' instead of 'zsh' in my mac.

Open Terminal.
Confirm you have JDK by typing “which java”. ...
Check you have the needed version of Java, by typing
“java -version”.
Set JAVA_HOME using this command in Terminal: export
JAVA_HOME=/Library/Java/Home.
echo $JAVA_HOME on Terminal to confirm
the path.

More simply on a mac terminal with a modern OSX
$ vim ~/.zshrc
Type "a" to being editing, and then paste (ctrl + v):
$ JAVA_HOME=/usr/libexec/java_home
then hit "escape" and type exactly ":wq" in order to write to the file and quit vim mode.
Finally, when out of vim mode and back in your terminal, type
$ source ~/.zshrc
This will refresh so that your terminal is aware of the changes.
IMPORTANT * If you don't "source" the file, you won't see the changes in this terminal session.
Check the changes by typing
$ echo $JAVA_HOME
and you should see /usr/libexec/java_home

Quick Guide for M1
Add java sdk into your m1
check version
java --version
Get all java versions installed in ur mac
/usr/libexec/java_home -V
Execute for Java path from library
/usr/libexec/java_home
(specify java version if you have multiple version, In my case -v17.0.5
/usr/libexec/java_home -v17.0.5
Mac>User>'YourUserName/Home'>.zshrc
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-17.0.5.jdk/Contents/Home