ADDITIONAL SYSTEM INFORMATION :
Oracle Build of Java 17

java 17.0.7 2023-04-18 LTS
Java(TM) SE Runtime Environment (build 17.0.7+8-LTS-224)
Java HotSpot(TM) 64-Bit Server VM (build 17.0.7+8-LTS-224, mixed mode, sharing)

Same issue with OpenJDK 20.

A DESCRIPTION OF THE PROBLEM :
When compiling with the "--release" flag set to version 8, JDK 17 cannot find sun.awt.* packages.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile the source code with "javac --release 8 AwtTest.java"

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Since a JDK 8 rt.jar contains sun.awt.*, I would expect the code to compile without errors.

From JEP 247: "For N < 9, the documented APIs consist of the public APIs that were on javac's default bootclasspath for JDK N."
ACTUAL -
.\AwtTest.java:1: error: package sun.awt does not exist
import sun.awt.CausedFocusEvent;

---------- BEGIN SOURCE ----------
import sun.awt.CausedFocusEvent;

public class AwtTest {

}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Use a separate Java 8 JDK to compile this code