Time for action: passing command parameters

Displaying a message to System.out shows that the command works, but what if the command needed to pick up local state? Fortunately, the @Named and @Inject annotations allow objects to be injected into the method when it is called.

1. Modify the hello method so that instead of printing a message to System.out, it opens a dialog window, using the active shell:

   public void hello(@Named(IServiceConstants.ACTIVE_SHELL) Shell s){
     MessageDialog.openInformation(s, "Hello World",
       "Welcome to Eclipse 4 technology");
   }

2. Other arguments can be passed in from the context, managed by the IEclipseContext interface. For example, using the math.random function from earlier, a value could be injected into the handler:

   public void hello(@Named(IServiceConstants.ACTIVE_SHELL) Shell s,
     @Named("math.random") double value) {

3. If the same handler is being used for different functions (for example, Paste and Paste Special), they can be disambiguated by passing in a hard...