java - Eclipse RCP 4 - Handler method parameters -

i'm taking new eclipse rcp framework , have questions handlers. in rcp 3.x handler class needed implement interface, methods given. in rcp 4 handler class doesn't need implement interface. instead annotate methods. e.g. if have exithandler in vogellas tutorial have @execute annotation. can see, there's iworkbench parameter passed.

package com.example.e4.rcp.todo.handler;  import org.eclipse.e4.core.di.annotations.execute; import org.eclipse.e4.ui.workbench.iworkbench;  public class exithandler {   @execute   public void execute(iworkbench workbench) {     workbench.close();   } }  

my question is: how know parameters passed when using annotations? how know in case iworkbench object , not window object or something? in fact can annotate method without parameter , still executed.

is there documentation somewhere? eclipse e4 tools don't seem support me there either...

the annotation @execute doesn't determine type injected, method declaration does.

as behavior annotation, @execute marks method should called when handler executed. type of object injected determined method's arguments. inject object type, change method's argument, e.g.

@execute public void execute(mwindow window) {     // method body } 

to inject mwindow active context.

the @execute annotation contains @inject annotation, when event triggered , handler going executed following happens:

1. the framework looks method marked @execute annotation
2. the e4 context searched object of method's argument type (e.g. iworkbench)
3. the object gets injected , method executed

unless @optional annotation set, exception thrown if no object found in context.

for further reading , more thorough explanations see eclipse 4 (e4) tutorial part 4- dependency injection basics , eclipse 4 (e4) tutorial part 6: behavior annotations.

an overview of eclipse 4 annotations can found @ eclipse 4 wiki.