public class XMLEditor extends TextEditor ... { // IContentOutlinePageの実装クラス private XMLOutlinePage outlinePage; ... public void dispose() { if(outlinePage!=null){ outlinePage.dispose(); } ... } public Object getAdapter(Class adapter) { if(IContentOutlinePage.class.equals(adapter)){ if(outlinePage==null){ outlinePage = new XMLOutlinePage(this); } return outlinePage; } return super.getAdapter(adapt