The problem that you are seeing is because jenv is not setup properly for your terminal. Depending on your terminal, you should look at your .bash_profile or .zshrc and ensure that the following lines exist:
Copyexport PATH="$HOME/.jenv/bin:$PATH"
eval "$(jenv init -)"
You can test to see if jenv has been initialized properly in your terminal by running which java. If jenv is initialized properly you will see something like:
Copy/Users/your-username/.jenv/shims/java
If you don't see this, double check .bash_profile or .zshrc as described above. I also recommend that you place these at the end of the file so that you can be sure that jenv gets added onto the start of your PATH.
The magic behind jenv is jenv init. When you open your terminal this runs and updates your PATH to look at ~/.jenv/shims which contains a shim (shell script) which resolves your desired version of Java when you run java or other JRE/JDK commands.
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The problem that you are seeing is because jenv is not setup properly for your terminal. Depending on your terminal, you should look at your .bash_profile or .zshrc and ensure that the following lines exist:
Copyexport PATH="$HOME/.jenv/bin:$PATH"
eval "$(jenv init -)"
You can test to see if jenv has been initialized properly in your terminal by running which java. If jenv is initialized properly you will see something like:
Copy/Users/your-username/.jenv/shims/java
If you don't see this, double check .bash_profile or .zshrc as described above. I also recommend that you place these at the end of the file so that you can be sure that jenv gets added onto the start of your PATH.
The magic behind jenv is jenv init. When you open your terminal this runs and updates your PATH to look at ~/.jenv/shims which contains a shim (shell script) which resolves your desired version of Java when you run java or other JRE/JDK commands.
Behind the scenes jenv uses the /Library/Java/JavaVirtualMachines directory.
Then you could also type /usr/libexec/java_home -V to show all the available JDKs and analyse your issue:
CopyMatching Java Virtual Machines (4):
11.0.2_2-OracleJDK, x86_64: "Java SE 11.0.2" /Library/Java/JavaVirtualMachines/OracleJDK-jdk-11.0.2.jdk/Contents/Home
11.0.2_1-OpenJDK, x86_64: "OpenJDK 11.0.2" /Library/Java/JavaVirtualMachines/OpenJDK-jdk-11.0.2.jdk/Contents/Home
1.8.0_11, x86_64: "Java SE 8" /Library/Java/JavaVirtualMachines/jdk1.8.0_11.jdk/Contents/Home
1.7.0_45, x86_64: "Java SE 7" /Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home
/Library/Java/JavaVirtualMachines/OracleJDK-jdk-11.0.2.jdk/Contents/Home
In this exemple export JAVA_HOME=$(/usr/libexec/java_home -v 1.8) set the JDK 1.8 version.
Thus, you even could define the following aliases:
Copyjava11_OpenJDK_export='export JAVA_HOME=$(/usr/libexec/java_home -v 11.0.2_1-OpenJDK)'
java11_OracleJDK_export='export JAVA_HOME=$(/usr/libexec/java_home -v 11.0.2_2-OracleJDK)'
java7_export='export JAVA_HOME=$(/usr/libexec/java_home -v 1.7)'
java8_export='export JAVA_HOME=$(/usr/libexec/java_home -v 1.8)'
NB: The version to use after java_home -v is defined in each JDK installation in the Contents/Info.plist file section JVMVersion.
I changed it, to easily switch between the OpenJDK and the Oracle JDK:
Copy$ tail -5 /Library/Java/JavaVirtualMachines/OpenJDK-jdk-11.0.2.jdk/Contents/Info.plist | head -2
<key>JVMVersion</key>
<string>11.0.2_1-OpenJDK</string>
$ tail -5 /Library/Java/JavaVirtualMachines/OracleJDK-jdk-11.0.2.jdk/Contents/Info.plist | head -2
<key>JVMVersion</key>
<string>11.0.2_2-OracleJDK</string>
So, in your case as you have two 1.8 versions (1.8 and 1.8.0.252). It is more than likely that you should update their Contents/Info.plist file section JVMVersion.
I executed in terminal:
echo 'export PATH="$HOME/.jenv/bin:$PATH"' >> ~/.bash_profile
echo 'eval "$(jenv init -)"' >> ~/.bash_profile
And after it could configure jenv as it is described on the manual page. However, it didn't take effect:
sdos-MacBook-Pro:~ nazar$ jenv versions
system
1.8
* 1.8.0.192 (set by /Users/nazar/.jenv/version)
11.0
11.0.1
openjdk64-11.0.1
oracle64-1.8.0.192
sdos-MacBook-Pro:~ nazar$ java -version
openjdk version "11.0.1" 2018-10-16
Only after opening new terminal I could see:
sdos-MacBook-Pro:~ nazar$ java -version
java version "1.8.0_192"
Java(TM) SE Runtime Environment (build 1.8.0_192-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.192-b12, mixed mode)
Not knowning about jenv, but macOS comes with a tool /usr/libexec/java_home to switch java version
Please refer to https://stackoverflow.com/questions/17885494/how-can-i-change-mac-oss-default-java-vm-returned-from-usr-libexec-java-home
According to documentation eval "$(jenv init -)" should print to console some command which you need to execute (they suggest to add them to .bash_profile).
jenv versions showed the current version was system. I am not sure why that version was not proper. I set the global version to 1.8.0.121 and everything is working as expected.