Eclipse RCP & ImageDescriptor

If you what to use icons, which located in project packages, but isn't defined as shared resources in ISharedImages you coud use it in such way:

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1. somthAction.setImageDescriptor(Plugin.imageDescriptorFromPlugin("org.eclipse.ui",  
2.     "/icons/full/etool16/save_edit.gif"));  

somthAction.setImageDescriptor(Plugin.imageDescriptorFromPlugin("org.eclipse.ui",
    "/icons/full/etool16/save_edit.gif"));