EMF学习--属性可以选择的对象集的过滤

1、先在新建的library插件工程中建立ecore模型。


2、根据ecore生成对应的genmodel，由genmodel生成对应的Model代码以及edit和editor两个相关插件。

3、从Borrower对象的属性books可选择的对象集中排除SchoolBook。
修改edit插件中的BorrowerItemProvider类的addBooksPropertyDescriptor方法，原代码为

/**
	 * This adds a property descriptor for the Books feature.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	protected void addBooksPropertyDescriptor(Object object) {
		itemPropertyDescriptors.add
			(createItemPropertyDescriptor
				(((ComposeableAdapterFactory)adapterFactory).getRootAdapterFactory(),
				 getResourceLocator(),
				 getString("_UI_Borrower_books_feature"),
				 getString("_UI_PropertyDescriptor_description", "_UI_Borrower_books_feature", "_UI_Borrower_type"),
				 LibraryPackage.Literals.BORROWER__BOOKS,
				 true,
				 false,
				 true,
				 null,
				 null,
				 null));
	}

修改为

/**
	 * This adds a property descriptor for the Books feature.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated NOT
	 */
	protected void addBooksPropertyDescriptor(Object object) {
		itemPropertyDescriptors.add
			(new ItemPropertyDescriptor
				(((ComposeableAdapterFactory)adapterFactory).getRootAdapterFactory(),
				 getResourceLocator(),
				 getString("_UI_Borrower_books_feature"),
				 getString("_UI_PropertyDescriptor_description", "_UI_Borrower_books_feature", "_UI_Borrower_type"),
				 LibraryPackage.Literals.BORROWER__BOOKS,
				 true,
				 false,
				 true,
				 null,
				 null,
				 null) {
				
				@Override
				public Collection<?> getChoiceOfValues(Object object) {
					Collection<Object> results = new ArrayList<Object>();
					for (Object _object : super.getChoiceOfValues(object)) {
						if (!(_object instanceof SchoolBook)) {
							results.add(_object);
						}
					}
					return results;
				}
				
			});
	}

4、这样改完之后就达到了属性选择对象的过滤效果。