workspace '--release' setting ignored by Problems View

[chrislake]

Steps to reproduce

From a fresh installation and clean workspace:

1. Window -> Preferences -> Java -> Installed JREs
   • Add Java 21 (or at least 19 I would suppose)
2. Window -> Preferences -> Java -> Compiler
   • Compiler Compliance level => 17
   • "Use '--release' option" checked
3. Create a new Java Project
4. Create a new Class

package foo;
import java.util.Locale;
class Main {
  public static void main(String[] args) {
    Locale l = new Locale("en", "US");
    System.out.println(l.getCountry());

    l = Locale.of("en", "US");
    System.out.println(l.getCountry());
  }
}

I tried

1. Right click on new project -> Properties -> Java Compiler

   • "Enable project specific settings" checked
   • "Use '--release option' UNchecked
   • Apply and close
   • Outcome in the Problems View is as I expect:
     • The constructor Locale(String, String) is deprecated since version 19

2. Right click on new project -> Properties -> Java Compiler

   • "Enable project specific settings" checked
   • "Use '--release option' checked
   • Apply and close
   • Outcome in the Problems View is as I expect:
     • The method of(String, String) is undefined for the type Locale

3. Right click on new project -> Properties -> Java Compiler

   • "Enable project specific settings" UNchecked
   • Apply and close
   • Outcome in the Problems View is not as expected:
     • The constructor Locale(String, String) is deprecated since version 19

I expected: The method of(String, String) is undefined for the type Locale as the '--release' option is checked in the workspace settings.

Tested under this environment:

• OS & version: Windows 10
• Eclipse IDE/Platform version (as shown in Help > About): 2024-06 (4.32.0)
• Java 21.0.3+9 used for the JDK

Community

• I understand reporting an issue to this OSS project does not mandate anyone to fix it. Other contributors may consider the issue, or not, at their own convenience. The most efficient way to get it fixed is that I fix it myself and contribute it back as a good quality patch to the project.

[merks]

Please open an issue for JDT:

https://github.com/eclipse-jdt/eclipse.jdt.core/issues

I can't move the issue so I'll close it here.