Applied Systems Analysis Fall 2003

Applied Systems AnalysisFall 2003 Class Notes 3 • Douglas Low • (315) 456-3372 (work) 2 min question • (315) 703-6297 (home) 5 min question • (315) 445-6044 (Lemoyne mailbox) leave message

Many Flavors of Process Whitten Scope Definition Problem Analysis Requirements Analysis Logical Design Decision Analysis Physical Design Construct & test Install & deliver Operate • Analysis • Design • Build • Test • Deploy RUP Inception Elaboration Construction Transition

What is Architecture? • System Architecture is the highest-level abstraction of a system, set in its intended environment. It includes; a set of components, the interfaces between the components, and the rationale for those choices in terms of the customer needs. • The Architecture Description is a model, which can communicate the system architecture to the system stakeholders. It should include: • Customer needs including requirements and constraints • Key decision points or issues and the basis for the resolution of the issues • Description of the components • Description of the interfaces; external and internal

Architecture Views (partial set) The architecture can be depicted using several approaches or views at the same time depending on the system. Some of the views include: • Behavioral or Dynamic view shows the sequence of events between components. (use cases, interaction diagrams, activity diagrams) • Static view shows the system decomposition in terms of a set of components at multiple levels. (Domain Model, class diagrams) • Structural or Data view shows the data flow between components as well as external to the system. (Data flow diagram, Context diagram) • Physical or Deployment view and Network view shows the components placement on hardware resources and the Physical connections

Domain Model • High level entities • Little bit tricky but theses are usually based on the “nouns” in the system description. • Entities are the things in your system or tht interact with your system. • Domain model is the first try at your class structure. • Your Domain model gets refined into your class structure. Your first try at the domain model can be wrong. You will refine it as you mature the design.

Class / Object Your_car:automobile Color Top-speed # doors Start Accelerate Decelerate Stop Object:Class Attributes (private, public, protected) • Object • A discrete entity with a well-defined boundary and identity that encapsulates state and behavior; an instance of a class • Class • A descriptor of a set of objects that share the same attributes, operations, and behavior. • A class has a set of attributes (data) and methods (operations) Methods (private, public, protected) Example class

Principles of Object-Oriented Modeling • Encapsulation • Inheritance • Polymorphism

Encapsulation • Combine information and behavior that • acts upon that information. • Package both into an object.

Encapsulation

Limits the effects of changes to the system. • Any changes to an object can be • implemented in the object. Encapsulation Benefits • Packaging of several items together into • one unit. • Related to information hiding. • The ability to hide the details about an • object. • Provides flexibility.

Inheritance • Mechanism that permits creation of new • objects based on old objects. • The child inherits the qualities of the • parent object. • One of the major benefits is ease of • maintenance.

Inheritance • Exploits commonalities between objects • and classes • When something changes that is common, • only the parent object needs to change. • Example: a system with 125 windows. A • user requests a change in the display. • Referred to as generalization or • specialization

Inheritance ACCOUNTS Account_number Interest_rate Owner Compute_Interest ( ) • Inheritance a major • advantage of OOAD. • Code can be reused. Account type (Incomplete, disjoint) CREDIT_CARD Credit_Limit Minimum_Payment Compute_Fees ( ) CHECKING_ACCOUNT Check_Issue_date SAVINGS_ACCOUNT

Polymorphism • Having many different forms or • Implementations of functionality • Behavior: speak • Implementation: • human: “hello” • dog: “woof” • cat: “meow” Add(1, 6) Add (person, people) Add (Item , list)

Associations Associations between classes should denote an interface, aggregation or generalization Association 1 * supports Multiplicity Association Name Examples of Multiplicity 1-* 1 to n 1-3 1 - 3 * 0 - n

Composition or Aggregation car Interior Wheels Engine Body • Aggregation • A form of association that defines the whole / part relationship

Generalization • A relationship between a general class and a more specific class that builds on it and extends it. • The classes take on a parent child nomenclature with the more specific class is the child of the general patent class. • Children inherit behavior from their parents. (explained later)

Inheritance • Attributes and Operations are inherited by the children of a super class. • Children have all of the capabilities of the parents plus additional ones of their own.

Linkage of Requirements, use cases analysis’ etc.

Req – Req Linkage Level X Requirement Level X Requirement Level X (System, Segment, Element, component) Level X-1 Source Linkage Allocated Requirement Allocated Requirement Derived Requirement Derived Requirement Element Ownership Linkage Element

Use Case Linkage Level X Requirement Level X Level X-1 Level X Use Case Level X Test Case Source Linkage Level X-1 Requirement Element Ownership Linkage Level X-1 Use Case Level X-1 Test Case

Use Case Linkage Parent Parent Child Child System/Segment Enterprise CI Every Use case is linked to a use case at the next higher level

Issue – Sibling Use cases CI (a) Problem: Assure that the behavior of element actors are properly defined from each side of the interface CI (b) • If an element of a CI is an actor to another CI; (Element Actor) • The use case must have an associated use case in the other CI; (Sibling Use case) Element of CI(b) Rule: Element actors share an interface in their associated CI Element of CI(a) Rule: Sibling use cases must share the same parent use case • Should have a means to navigate, check and view sibling use cases

System Description Requirements • The system shall automatically feed raw material from the input hopper and into the pre-processor. • The system shall automatically feed preprocessed material from the pre processor into the processor. • The automation shall be controlled by a computer system. • The computer system shall control temperature, pressure and humidity in the pre-processing stage. • The system shall control preprocessing parameters based on user defined input data. • The system shall automatically control the level of sodium hydroxide solution in the processor. • The system shall automatically drain and dry the mixture in the processor. • The system shall control the processing based on user define input parameters. • The system shall alert the operator when the batch is finished. • The system shall diagnose problems in the system and isolate the fault down to an LRU. • The system to be developed is a precious metal (PM) generator. It creates gold & silver from the raw material rabbit poop. • The entire process is automated including automatic feed of raw material into the processing mechanism and automatically feed finished material into a store room after the PM is created. The automation is controlled by a computer system computer software. • The entire process is performed in batches. • The process of creating PM requires preprocessing. During preprocessing the raw material is brought to a specified temperature and pressure and humidity and maintained within predefined limits for a predefined length of time. • Processing of the preprocessed material includes several steps: • Dissolve the preprocess batch in a sodium hydroxide solution. Produce and maintain 100 degrees F temperature. Wait for 1 hour • Add 6 grains of a secret ingredient. Stir for 1 minute. • Solution is pumped through a filter and the effluent is disposed of to a city drain. • The filter now contains PM. The Filter is dried using a forced air heater. The PM dust is collected from the filter through a funnel and onto the conveyer which is transferred to the store room via a conveyor belt. • After the process is completed the system sounds an signal to indicate to the operator to provide more raw material. • The system is self diagnosing and will provide the maintainers with the problem and solution.

Requirements to Usecase • Create PM • Create PM • Create PM • Create PM • Create PM • define user parameters • Create PM • Create PM • Crete PM • define user parameters • Create PM • Diagnose problems • The system shall automatically feed raw material from the input hopper and into the pre-processor. • The system shall automatically feed preprocessed material from the pre processor into the processor. • The automation shall be controlled by a computer system. • The computer system shall control temperature, pressure and humidity in the pre-processing stage. • The system shall control preprocessing parameters based on user defined input data. • The system shall allow the operator to input and verify preprocessing parameters. • The system shall automatically control the level of sodium hydroxide solution in the processor. • The system shall automatically drain and dry the mixture in the processor. • The system shall control the processing based on user define input parameters. • The system shall allow the user to input and verify processing parameters. • The system shall alert the operator when the batch is finished. • The system shall diagnose problems in the system and isolate the fault down to an LRU.

Use Case Description Use Case 1 Documentation Set • 3.2.4.1 CSCI Capability 1 Infrastructure • 3.2.4.1.1 Capability 1 Use Case 1 (Summary) • 3.2.4.1.1.1 Preconditions • 3.2.4.1.1.2 Post conditions • 3.2.4.1.1.3 Primary flow of events • 3.2.4.1.1.3.1 Sequence Diagrams • 3.2.4.1.1.4 Alternate flow of events • 3.2.4.1.1.4.1 Sequence Diagrams • 3.2.4.1.1.5 Exception flow of events • 3.2.4.1.1.5.1 Sequence Diagrams Include Trigger Include Trigger Include Trigger • 3.2.4.1.n Capability 1 Use Case n • Use Case n Documentation Set • 3.2.4.n CSCI Capability x ______________ • 3.2.4.x.m Capability n Use Case m

Create PM Main Flow Use Case Description • Main Flow Summary • The system will automatically take the raw materials from a hopper process it into PM then add the PM to the store room . The entire process is automatic and maintenance free. All you have to do is add material. It take a full hopper of raw material to create one pound of final product. • 3.2.4.1.1.1 Preconditions • The system has been started and initialized and is running in idle state. The material hopper is full of raw material. Filter paper is available chemical bins have material. • 3.2.4.1.1.2 Post conditions • Store room is increased by one pound of pure PM. • 3.2.4.1.1.3 Primary flow of events • The operator initiates the process by pressing the run button. The raw material is transferred to the preprocessor automatically by a conveyor mechanism. As the material is preprocessed the system keeps track of the amount of raw material is processes and display the value on the control panel along with the elapsed time. The preprocessor maintains temperature, pressure humidity and oxygen level for a time period. All of the parameters are adjustable (see use case Start System. • As the material is preprocessed, it is transferred into the main processor by an automated conveyor. • If any one of the parameters is out of specification by the predefined amount, and error report is generated and the use case is terminated.(E1). • If no errors resulted from the preprocessing stage. The processor is automatically initiated after all of the raw material is preprocessed. The timer is initiated upon initiation of the processor. • When a pre determined time as elapsed, the system automatically send the processed material to the store room via a material conveyer.This is the end of the use case • 3.2.4.1.1.3.1 Sequence Diagrams • 3.2.4.1.1.4 Alternate flow of events • 3.2.4.1.1.4.1 Sequence Diagrams • 3.2.4.1.1.5 Exception flow of events • 3.2.4.1.1.5.1 Sequence Diagrams Can You find the Problems? What are the alternate flows? What are the exception flows?

PM Hardware system Sodium Hydroxide solution Hopper Input conveyor Secret ingredient • Control • Temp • Pressure • Humidity Preprocessor Door 1 Valve 1 Processor Valve 3 • Control • level Forced air Blower / heater Filter paper Dispenser Filter enclosure Valve 2 Door 2 funnel output conveyor To Store room

PM Machine Class Diagram

What is in an OO SRS? • Use Cases • Model • Relationships • Interaction • Behavior • Scenarios • Stereotypes • UML • Packages • Classes / Objects • Inheritance • Generalization • Aggregation • Actors • Diagrams • State diagram • Activity diagram • Use Cases diagrams • Sequence Diagrams • Collaboration Diagrams • Deployment diagram • Class / Object diagram • Hidden/private data • Methods / operations

Interaction Diagrams • Interaction – specification of how messages are sent between objects to perform a task. • Interaction diagrams: sequence, collaboration • Sequence diagram shows the behavior dynamically while the collaboration diagram shows it statically.

Sequence Diagrams Time • A two dimensional chart that displays a sequence of behavior and interaction between objects. • The vertical dimension is time (non linear) while the horizontal depicts the objects. Calls Self Process Return message

Example Sequence Diagram

Reference Interaction (UML2 only)

Example Collaboration Diagram Procedure Call Object:Class Trigger Message Trigger message Flat message Optional Return Message() Procedure call() :Class External System

Homework 3 • Read Boggs Chap 2 & 4 (skip 3) • Read Whitten Chapter 6 • Finish 3 - PM use cases

Applied Systems Analysis Fall 2003