IWorkbenchPart的生命周期

IWorkbenchPart的子类有IViewPart(视图)和IEditorPart(编辑器)。
通过查看IWorkbenchPart的源码，其描述如下：

1.part.init(site)
2.part.createControl(parent)
3.part.setFocus()
4.part.dispose()

源代码中的注释
 * The lifecycle of a workbench part is as follows:
 * <ul>
 *  <li>When a part extension is created:
 *    <ul>
 *  <li>instantiate the part</li>
 *  <li>create a part site</li>
 *  <li>call <code>part.init(site)</code></li>
 *    </ul>
 *  <li>When a part becomes visible in the workbench:
 *    <ul>
 *  <li>add part to presentation by calling
 *        <code>part.createControl(parent)</code> to create actual widgets</li>
 *  <li>fire <code>partOpened</code> event to all listeners</li>
 *   </ul>
 *   </li>
 *  <li>When a part is activated or gets focus:
 *    <ul>
 *  <li>call <code>part.setFocus()</code></li>
 *  <li>fire <code>partActivated</code> event to all listeners</li>
 *   </ul>
 *   </li>
 *  <li>When a part is closed:
 *    <ul>
 *  <li>if save is needed, do save; if it fails or is canceled return</li>
 *  <li>if part is active, deactivate part</li>
 *  <li>fire <code>partClosed</code> event to all listeners</li>
 *  <li>remove part from presentation; part controls are disposed as part
 *         of the SWT widget tree
 *  <li>call <code>part.dispose()</code></li>
 *   </ul>
 *   </li>
 * </ul>
 * </p>
 * <p>