Model

The Model is an abstract set of interfaces that encapsulate any code in the system that could possibly have multiple realisations. The Model is split into a set of discrete components, each with its own factory for generating classes supporting the defined interfaces. The discrete components currently in the Model are the auto assignment algorithms, the database access objects, sending mail, session authentication, the testing framework, and administrative operations.

Factories

Each component of the Model has its own factory to generate classes compliant with the interfaces the model defines. A factory Registrar is used to register implementations for particular interfaces. It is the responsibility of a program to register factory interfaces with the Registrar, and the frontend does this by reading a factories.properties file and using introspection.

Factories derive from the Factory interface, which requires methods for Factories to explain which configuration options they require, and these are used for automatic configuration the first time BOSS2 is run.

Components

Auto assignment algorithms

Auto assignment algorithms are responsible for assigning markers to students automatically. The Factory provides methods to query what algorithms are available and their class names. The implementing classes themselves provide a single method that takes a list of markers, a list of students, and returns a map of markers to the students that they will mark.

Name	Package	Factory
Auto Assignment Algorithms	uk.ac.warwick.dcs.boss.model.autoassignment	AutoAssignmentMethodFactory

Data access objects

Data access objects are responsible for brokering persistent storage. The model defines a set of beans that may be stored in the database. and a set of query results that are returned by DAOs tailored for Student, Staff, Marker and Admin operations. The Factory provides methods to initialise storage, begin/end/abort transactions, and obtain objects to broker these beans with the storage. Brokerage is done by a persistent identifier (which is a java.lang.Long).

Name	Package	Factory
Data Access Objects	uk.ac.warwick.dcs.boss.model.dao	DAOFactory

Beans defined for storage

Name	Description	Dependencies	Comment
Assignment	An assignment	Module, Person, Resource	DAO provides access to markers
DeadlineRevision	A deadline revision	Assignment, Person
Entity	Generic entity in the database		No DAO, used internally
Mark	A mark	MarkingAssignment, Person
MarkingAssignment	A binding of student to marker	Assignment, Person
MarkingCategory	A marking category	Assignment
Model	A model		Top level entity in the model tree
Module	A module	Model, Person	DAO provides access to students and administrators
Person	A user of the BOSS2 system		Unique identifier doubles up as username
Resource	A stored resource (file)		DAO provides access to data via streams
Result	A published result	Assignment, Person
Submission	A submission	Assignment, Person, Resource
Test	A test	Assignment, Resource	DAO provides access to parameters

Specialised query results

DAO	Queries	Result	Used by
IAdminInterfaceQueriesDAO	Fetching models to administrate	AdminModelsQueryResult	Aministrator 'model management' page
IAdminInterfaceQueriesDAO	Fetching modules for a model	AdminModulesQueryResult	Administrator 'module management' page
IMarkerInterfaceQueriesDAO	Fetching assignments to mark	MarkerAssignmentsQueryResult	Marker 'assignments to mark' page
IMarkerInterfaceQueriesDAO	Fetching marks for a marking assignment	MarkerMarksQueryResult	Marker 'marks for a student' page
IMarkerInterfaceQueriesDAO	Fetching students to mark for an assignment	MarkerStudentsQueryResult	Marker 'students to mark' page
IMarkerInterfaceQueriesDAO	Fetching submissions by a student for an assignment	MarkerSubmissionsQueryResult	Marker 'submissions by student' page
IStaffInterfaceQueriesDAO	Fetching assignments for a module	StaffAssignmentsQueryResult	Staff 'assignments' page
IStaffInterfaceQueriesDAO	Fetching deadline revisiosn for an assignment	StaffDeadlineRevisionsQueryResult	Staff 'deadline revisions' page
IStaffInterfaceQueriesDAO	Fetching marking assignments for an assignment	StaffMarkingAssignmentsQueryResult	Staff 'marking assignments' page
IStaffInterfaceQueriesDAO	Fetching modules to adminsitrate	StaffModulesQueryResult	Staff 'modules' page
IStaffInterfaceQueriesDAO	Fetching results for an assignment	StaffResultsQueryResult	Staff 'results' page
IStaffInterfaceQueriesDAO	Fetching submissions for an asignment	StaffSubmissionsQueryResult	Staff 'submissions' page
IStudentInterfaceQueriesDAO	Fetching assignments to submit or details for an assignment	StudentAssignmentsQueryResult	Multiple student pages
IStudentInterfaceQueriesDAO	Fetching modules that have assignments to submit to	StudentModulesQueryResult	Student 'modules' page
IStudentInterfaceQueriesDAO	Fetching assignments you have previously submitted to	StudentSubmissionCountsQueryResult	Student 'previous submissions' page
IStudentInterfaceQueriesDAO	Fetching submissions previously submitted to an assignment	StudentSubmissionsQueryResult	Student 'submissions for assignment' page

Sending mail

Mail sending is used for communicating with students, typically via email (although IM could easily be used instead). The Factory provides a method to get an object that can send mails. Mails have a recipient, a subject, and a message and are sent asynchronously.

Name	Package	Factory
Sending Mail	uk.ac.warwick.dcs.boss.model.mail	MailFactory

Session authentication

The Factory provides a method to get an object that can authenticate users or change their authentication credentials. A successful login generates a session which contains the Person that logged in, a preferred locale (currently unused), future test results, and an arbitrary session memory.

Note: Future test results should be moved out of the session and into the testing framework at some point.

Name	Package	Factory
Session Authentication	uk.ac.warwick.dcs.boss.model.session	SessionAuthenticationFactory

Testing framework

The testing framework is responsible for running tests on the submissions.

Name	Package	Factory
Test Runner	uk.ac.warwick.dcs.boss.model.testing	TestRunnerFactory
Test Method	uk.ac.warwick.dcs.boss.model.testing.methods	TestMethodFactory
Test Executor	uk.ac.warwick.dcs.boss.model.testing.executors	TestExecutorFactory

Test Runner

The test runner is responsible for queuing tests given a submission and a test. It is responsible for unpacking the submission and test resources, running the test executor and feeding the results into the test method. The test runner returns Future TestResult objects for accessing test results when they are complete, and TestRunnerFactory provides a method to generate an object that can queue tests given a submission and a test.

NOTE: Future test results are currently stored in the session by the controller. This is bad, and the Test Runner really should handle this.

Test Method

A test method takes an ExecutionResult object and returns a TestResult object. The TestMethodFactory provides methods to query which test methods are available and their class names.

Test Executor

A test executor takes a submission directory, a test resource directory, and a command to run and generates an ExecutionResult object. TestExecutorFactory provides methods to query which test executors are available and their class names.

Administrative operations

An administration operation takes parameters and performs some form of operation, returning an AdminUtilityResult. The AdminUtilityFactory provides methods to query which operations are available and their class names.

Name	Package	Factory
Administration Operations	uk.ac.warwick.dcs.boss.model.utilities	AdminUtilityFactory