###Understanding Java Version Queries
Java provides specific command-line options to check the installed version. The output can vary slightly based on the Java vendor (Oracle, OpenJDK, etc.) but generally follows a consistent format displaying the version, runtime environment, and VM information.
Here's a concise key/value pair list of commands you might use to query Java version information, along with the expected type of output for each:
-
java -version
: This is the correct and standard command to get the Java version, the runtime environment, and VM details. Expected output: Detailed version information. -
java --version
: This is essentially the same asjava -version
and is accepted by newer versions of Java as a valid command. Expected output: Detailed version information, similar tojava -version
. -
java -v
: Expected output: This command is not recognized by Java, and you will likely receive an error message indicating an unrecognized option. -
java --v
: Expected output: Similar tojava -v
, this is not a recognized command in Java, and you will receive an error message.
The commands java -v
and java --v
do not provide version information because they are not recognized syntax for querying Java version details. The standardized commands across most Java versions and distributions for obtaining version information are java -version
and java --version
.