级联测试“级联什么? “-拓冰建站

在应用程序中, 当你对子对象进行了一些改变，你肯定不希望需要自己去想着还需要对父对象进行哪些操作，这样是非常繁琐的。好在 NHibernate 提供了级联的功能，你不需要做这些事了。如果你的映射是正确的，你就只需要保存子对象，其他的工作你都不需要理会。

对于一些人，尤其像我这样的，这是一个很大的工作量，这就是为什么我们要测试映射。

[Test()] public void CanCascadeSaveFromCourseToSections() { using (SQLiteDatabaseScope<CourseMapping> Scope = new SQLiteDatabaseScope<CourseMapping>()) { using (ISession Session = Scope.OpenSession()) { Guid ID; Term Term = new Term { Name = "Fall 2009", StartDate = new System.DateTime(2009, 9, 1), EndDate = new System.DateTime(2009, 12, 1) }; //We're not testing the cascade of section -> term here using (ITransaction Tran = Session.BeginTransaction()) { Session.Save(Term); Tran.Commit(); } Session.Clear(); Course Course = new Course { Subject = "SUBJ", CourseNumber = "1234", Title = "Title", Description = "Description", Hours = 3 }; Section Section1 = new Section { FacultyName = "FacultyName", RoomNumber = "R1", SectionNumber = "1", Term = Term }; Section Section2 = new Section { FacultyName = "FacultyName", RoomNumber = "R1", SectionNumber = "2", Term = Term }; Course.AddSection(Section1); Course.AddSection(Section2); //Test saving using (ITransaction Tran = Session.BeginTransaction()) { ID = (Guid) Session.Save(Course); Tran.Commit(); } Session.Clear(); //Check the results using (ITransaction Tran = Session.BeginTransaction()) { Course = Session.Get<Course>(ID); Assert.AreEqual(2, Course.Sections.Count); Assert.AreEqual(1, Course.Sections .Where(S => S.Equals(Section1)).Count(), "Course.Sections does not contain section 1."); Assert.AreEqual(1, Course.Sections .Where(S => S.Equals(Section2)).Count(), "Course.Sections does not contain section 2."); Tran.Commit(); } } } }

上面的测试将确保档你保存 course 的时候，也同样会保存对 section 的操作。下面看看它是如何工作的：

获取一个新的 SQLite 数据库
虽然我们不会测试 term ，但是因为 section 的需要，所以我们也需要在数据库中建立
创建一个 course 和两个 section
保存 course
清空 session
获取到 course
确保它有两个 section

当你从 course 中移除一个 section 将会发生什么呢？当然，任何一个 section 都需要有一个父对象，也就是 course 。请记住，我们在映射里指定的是非空的。更重要的是，现实世界中不会有独立的 section 。所以，当 section 成为孤儿的时候，它将被删除掉，下面我们来进行这样的一个测试：

[Test()] public void CanCascadeOrphanDeleteFromCourseToSections() { using (SQLiteDatabaseScope<CourseMapping> Scope = new SQLiteDatabaseScope<CourseMapping>()) { using (ISession Session = Scope.OpenSession()) { Guid ID; Term Term = new Term { Name = "Fall 2009", StartDate = new System.DateTime(2009, 9, 1), EndDate = new System.DateTime(2009, 12, 1) }; using (ITransaction Tran = Session.BeginTransaction()) { //We're not testing the cascade of section -> term here Session.Save(Term); Tran.Commit(); } Session.Clear(); Course Course = new Course { Subject = "SUBJ", CourseNumber = "1234", Title = "Title", Description = "Description", Hours = 3 }; Section Section1 = new Section { FacultyName = "FacultyName", RoomNumber = "R1", SectionNumber = "1", Term = Term }; Section Section2 = new Section { FacultyName = "FacultyName", RoomNumber = "R1", SectionNumber = "2", Term = Term }; Course.AddSection(Section1); Course.AddSection(Section2); using (ITransaction Tran = Session.BeginTransaction()) { Session.Save(Course); Tran.Commit(); } Session.Clear(); //Test removing Course.RemoveSection(Section1); using (ITransaction Tran = Session.BeginTransaction()) { ID = (Guid) Session.Save(Course); Tran.Commit(); } Session.Clear(); //Check the results using (ITransaction Tran = Session.BeginTransaction()) { Course = Session.Get<Course>(ID); Assert.AreEqual(1, Course.Sections.Count()); Assert.AreEqual(0, Course.Sections .Where(S => S.Equals(Section1)).Count(), "Course.Sections still contains section 1"); Tran.Commit(); } } } }

我希望大家能和我是一样的心态，除了查询测试，当我们写 DAO 层的时候，就要对 NHibernate 进行测试。我们对其他的实体类也都要进行相同类型的测试。