private EditorProvider reuseExistingEditor(DataType dataType) {
		DataTypeManager dataTypeManager = dataType.getDataTypeManager();
		if (dataTypeManager == null) {
			throw new IllegalArgumentException(
				"Datatype " + dataType.getName() + " doesn't have a data type manager specified.");
		}

		CategoryPath categoryPath = dataType.getCategoryPath();
		if (categoryPath == null) {
			throw new IllegalArgumentException(
				"DataType " + dataType.getName() + " has no category path!");
		}

		EditorProvider editor = getEditor(dataType);
		if (editor != null) {
			ComponentProvider componentProvider = editor.getComponentProvider();
			plugin.getTool().showComponentProvider(componentProvider, true);
			componentProvider.toFront();
		}
		return editor;
	}
Displays a data type editor for editing the given Structure. If the structure is already 
being edited then it is brought to the front. Otherwise, a new editor is created and 
displayed.
@param composite the structure.
@param fieldName the optional name of the field to select in the editor.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/datamgr/editor/DataTypeEditorManager.java