Description Mario Scalas 2005-11-17 10:59:03 EST

I'm trying to encapsulate the SWT thread safety in an aspect using the new
annotation style (but I've verified that rewriting the aspect using the "normal"
syntax changes nothing).

My aspect is:

package it.uniba.di.cdg.xcore.ui;

import it.uniba.di.cdg.xcore.util.RunnableWithReturn;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.eclipse.swt.widgets.Display;

@Aspect
public class SwtThreadSafety {
    @Pointcut( "call( @SwtSynchExec * *.*(..) )" )
    protected void uiSynchMethods() {}

    @Pointcut( "call( @SwtAsynchExec * *.*(..) )" )
    protected void uiAsynchMethods() {}

    @Around( "uiSynchMethods()" )
    public Object wrapSynchMethods( final ProceedingJoinPoint thisJoinPoint ) {
        RunnableWithReturn r = new RunnableWithReturn() {
            public void run() {
                try {
                    _returnValue = thisJoinPoint.proceed();
                } catch (Throwable e) {
                    throw new RuntimeException( e ); // Soft the exception ...
                }
            }
        };
        
        Display.getCurrent().asyncExec( r ); 
        return r.getReturnValue(); 
    }

    @Around( "uiAsynchMethods()" )
    public void wrapAsynchMethods( final ProceedingJoinPoint thisJoinPoint ) {
        Runnable r = new Runnable() {
            public void run() {
                try {
                    thisJoinPoint.proceed();
                } catch (Throwable e) {
                    throw new RuntimeException( e ); // Soft the exception ...
                }
            }
        };
        Display.getCurrent().asyncExec( r );
    }
}

@SwtAsynchExec and @SwtSynchExec are plain markers which define no property.

When I save the file the exception is thrown (see the uploaded stacktrace). This
is the interface containing the enum type:

package it.uniba.di.cdg.xcore.ui.views;

public interface IMessageBoard {
    enum LookType { SYSTEM, LOCAL_USER, BUDDY };
    
    void appendMessage( LookType look, String message );
}

If I change LookType to be a classe, the npe goes away (it is generated every
time I try to save the file and restarting the JDT changes nothing).