SWT runs on a different version of java-CodePudding

First and foremost, I know very little about Java and even less about SWT, so bare with me here. Earlier today I tried to run this simple program I found on https://mkyong.com/swt/swt-hello-world-example

here is the code:

import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

public class SWTHelloWorld {

public static void main (String [] args) {
    Display display = new Display ();
    Shell shell = new Shell(display);
    
    Text helloWorldTest = new Text(shell, SWT.NONE);
    helloWorldTest.setText("Hello World SWT");
    helloWorldTest.pack();
    
    shell.pack();
    shell.open ();
    while (!shell.isDisposed ()) {
        if (!display.readAndDispatch ()) display.sleep ();
    }
    display.dispose ();
}

When I run it I get this error:

Exception in thread "main" java.lang.UnsupportedClassVersionError: org/eclipse/swt/widgets/Composite has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0

What I understand from this is that SWT is getting compiled with Java 11 when it should be compiled with Java 8, BUT -and that's a big BUT- I don't have Java 11 I deleted it to only have Java 8 and avoid this kind of problems. When I run in my terminal the commands java -version and javac -version in both cases i get this version '1.8.0_331' and there is nothing else. I also checked my settings and configurations in Eclipse and everything seems to be set to run on Java 8. Ultimately I tried this command in the terminal javac -target 1.8.0_331 SWTHelloWorld.java to target the right compiler, but I got javac: invalid target release: 1.8.0_331. I don't know where to go from there. Anyone?

Thanks in advance guys!

PS: I'm on macOS Big Sur 11.4 if that matters.

CodePudding user response：

Uninstalling Java 11 does not change which version SWT itself was compiled for. Your application requires at least Java 11 because a library you're using, SWT, requires it.