The event broker always broadcasts to anything that is dealing with the event, you can't use it to send to one specific thing.
If you are in a Handler you can get the current part in the @Execute method and set a value directly in your class - something like:
@Execute
public void execute(@Named(IServiceConstants.ACTIVE_PART) MPart activePart)
{
Object part = activePart.getObject();
if (part instanceof MyClass)
{
((MyClass)part).setValue(xxxx);
}
}
Update:
If you are in another part use the EPartService
to get the active part:
@Inject
EPartService partService;
...
MPart activePart = partService.getActivePart();
Object part = activePart.getObject();
if (part instanceof MyClass)
{
((MyClass)part).setValue(xxxx);
}
You can also use EPartService.findPart("part id")
to find a part with a given id.