第一种：利用Action
IWorkbenchWindow window = getViewSite().getWorkbenchWindow();
IWorkbenchAction max = ActionFactory.MAXIMIZE.create(window);
max.run();

这段代码要放在何适的位置上才会起到合适的作用。

第二种：利用Zoom
在ApplicationWorkbenchWindowAdvisor#postWindowOpen中做到
public void postWindowOpen() {
     IWorkbenchWindow window = Plugin.getDefault().getWorkbench().getActiveWorkbenchWindow();
     IViewPart part=null;
     try {
         part = window.getActivePage().showView(View.ID);
     } catch (PartInitException e) {
         e.printStackTrace();
     }
  
     if(part!=null){
        window.getActivePage().activate(part); 
        window.getActivePage().bringToTop(part);
  
        WorkbenchPage realPage = (WorkbenchPage) window.getActivePage();

        IWorkbenchPartReference partRef = window.getActivePage().getActivePartReference();

        if (partRef != null) {
            ((WorkbenchPage) window.getActivePage()).toggleZoom(partRef);
        }else{
         System.out.println("partRef is null!");
        }
    }
}

原文地址 ：http://www.blogjava.net/hopeshared/archive/2006/03/27/37641.html