java -version throws "java.lang.ClassNotFoundException: "

Question

I am using OpenJDK 11 on Debian. Whenever I try to run java -version , I get this:

Error: Could not find or load main class 
Caused by: java.lang.ClassNotFoundException:

However, running like this works:

/usr/lib/jvm/java-11-openjdk-amd64/bin/java -version

I checked the symlinks, they all worked fine. If javac can work, why can't java , because both of them are in the same folder. What am I missing?

I get the same when trying to run any compiled classes. I recently tried (but failed) switching to a different JDK, before which I didn't have this problem. My $PATH and $JAVA_HOME are set correctly.

Answer 1

I finally found the answer. I took a step back, and thought out the exact steps I took when I changed my default JDK. When I had switched to 13, running java would echo a bunch of init settings on my screen, so I followed somebody's answer to suppress it, and THAT caused the error.

I had added this line to my.bash_profile to suppress it, and commenting it out followed by a reboot just solved the problem!

_SILENT_JAVA_OPTIONS="$_JAVA_OPTIONS" && unset _JAVA_OPTIONS &&  alias java='java "$_SILENT_JAVA_OPTIONS"'

PRO-TIP: If you're getting such errors, simply check which Environment variables could you have messed up with.