Knowledge Base

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.

====== Java Versioning ======

If you want to deploy .class files and your target system is using an older version of Java, you can specify the target version when you compile.  For example, if your development machine has Java 21 and your target machine has Java 17, you'd compile like this:

<code bash>
javac -source 17 -target 17 Main.java
</code>

When you compile, you may see a message similar to this:

<WRAP center round box 60%>
warning: [options] system modules path not set in conjunction with -source 17
</WRAP>

If so, you can also use Java's ''--release'' argument which combines the -source and -target arguments //and// automatically sets the modules path:

<code bash>
javac --release 17 Main.java
</code>

With either of these options, you'll see that the version has been set:

<code bash>
file Main.class
</code>

<WRAP center round box 60%>
Main.class: compiled Java class data, version 61.0 (Java SE 17)
</WRAP>

{{tag>java}}