CSci 210 --

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CSci 210 --  Advanced Software Paradigms Exam
Review

• A. Bellaachia
• Department of Computer Science
• School of Engineering and Applied ScienceThe
  George Washington University
• Washington, DC 20052

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Introduction

• Software Development Process
• Language and Computer Architecture
• Language paradigms
• Language Evaluation Criteria
• Readability
• Examples Data type, data structures, and control
  statements
• Writability
• Reliability
• Type checking
• Exception handling
• Aliasing
• Maintainability
• Cost 

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Software Paradigms

• Five Software Paradigms
• AP Algorithmic Paradigm
• AP assumes problem is well structured
• application program to map input to output
• finite number of steps, no errors
• ASE Analysis-Synthesis-Evaluation
• like Waterfall Model
• assumes problem is well structured
• It uses problem decomposition
• FD Formal Design
• FD assumes problem is well structured
• It is a refinement of ASE, but uses abstraction
• problem becomes a mathematical proposition
• AI Artificial Intelligence
• It is explicitly founded on the concepts of
  search, knowledge and heuristics
• It does not assume problem is well structured
• TED Theory of Evolutionary Design
• It uses the fast that software design is an
  evolutionary process
• It does not assume problem is well structured

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Software Architecture Paradigms

• Architectural Elements
• Processing elements
• Connecting elements
• Data Elements
• Configuration file

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Software Architecture Paradigms (Cont.)

• Architectural Styles (major ones)
• Dataflow Systems
• Pipelines
• Each layer is client for layer below it
• output of one stage input to next
• Example Compilers
• Call Return Systems
• Layered
• Each layer is client for layer below it
• advantages incremental, extendable
• N-tier / Client-Server
• layers can be developed independently
• Examples Operating Systems, Web-based
  applications
• Independent-Process
• Communicating Processes
• Using CSP to describe different process
  topologies
• Repository
• Blackboard
• central repository for shared info

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DSSA

• Requirement analysis and software architecture of
  a domain of applications.
• Examples Wed browsers, Web servers, Word
  processors, etc.
• There are three main elements of a DSSA
• Domain Model
• Complete description of the domain
• Achieved by experts in the domain, users,
  developers who have experience in the domain,
  etc.
• Reference Requirements
• Stable (or Fix)
• Variable (or optional)
• Requirements can also be broken into
• Functional, Non-functional, Design,
  Implementation
• List a reference of each requirement of the
  domain.
• Reference Architecture
• Make sure to state the right architecture style
  for the domain.
• List a reference of each architectural element.

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Components

• Why use components?
• Major elements of a component
• Specification
• One or more implementations
• Component Model
• Each of these component models addresses the
  following issues
• How a component makes its services available to
  others?
• How component are named?
• How new components and their services are
  discovered at runtime.
• A packaging approach
• Example 2EE application is packaged as an
  Enterprise ARchive (EAR) file, a standard Java
  JAR file with an .ear extension.
• A deployment approach
• J2EE uses deployment descriptors that are defined
  as in XML files named ejb-jar.xml.
• Component Architecture
• Blackbox vs. Whitebox
• Components vs. Objects
• Components in industry verses in-house solutions
• Component disadvantages

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Design Patterns

• Definitions
• What is a Pattern?
• Categories of Patterns
• Pattern Characteristics
• Essential Elements of a Design Pattern
• Examples of design patterns
• Singleton
• Adapter
• Strategy
• Design Pattern Selection
• How to Use a Design Pattern?
• Idioms

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Frameworks

• Definitions
• Frameworks
• Classification
• Frameworks Evaluation
• Examples

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Basic of Programming Languages

•  Built-in Types and Primitive Types
• Data Aggregates and Type Constructors
• Constructors
• User-defined Types and Abstract Data Types
• Strong Typing Type Checking
• Type Compatibility
• Type Conversion
• Type and Subtypes
• Generic Types
• Monomorphic versus Polymorphic
• The Type Structure of Representative languages
• Implementation Models
• Implementation of Structured Types

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Object-Oriented Programming

• Object-oriented characteristics
• Object Definition and instance creation
• Encapsulation
• Inheritance
• Polymorphism Polymorphism (Greek for many
  forms) means that the same operation can be
  defined for many different classes, and each can
  be implemented in their different way.
• Binding in OOP
• Static vs. Dynamics
• Implementation of OO constructs

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Functional Programming

• Functional programming characteristics
• Functions in FP composition, Apply-to-all, etc.
• Performance

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Logic Programming

• Logic programming characteristics
• based on relations.
• Horn clause
• User query processing
• Resolution
• Unification
• Performance

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Concurrency

• Concurrency requirements
• Problems with concurrency
• Deadlock
• Starvation
• Etc.
• Process Interactions
• Syntax for parallel processes
• Independent processes
• Competing processes (Critical sections)
• Communicating processes (May need to communicate)
• Low-level Concurrency Primitives
• Process creation and control
• Event Event-wait(e) and Event-signal(e)
• Messages
• Remote Procedure Calls (RPCs)
• Synchronization
• Semaphores, Monitors, etc.
• Concurrency in Java.

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Sample Question

• Problem
• In this problem, we would like to define a DSSA
  for web server applications such as Apache and
  Internet Information Server (IIS). The major
  operations of a web server include the
  following
• A resource handler to determine the type of
  operation requested by a browser.
• Interpretation of a request protocol such as the
  HTTP protocol.
• An operation, called Access Control, to enforce
  access rule employed by the server.
• A request analysis operation to translate the
  location of the resource (URL) from a network
  location to a local file name.
• A web server has also the ability to gather
  information (log) about all the requests and
  their results.
• Provide a complete DSSA for this type of
  applications.

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Sample Question

• Problem
• State the major software paradigms that can be
  examined during the steps of the software life
  cycle of an application and explain why.

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Sample Question

• Problem
• Component-based software development greatly
  depends on an efficient component integration
  strategy. You have been hired by a company and
  you are asked to develop a component-based
  system.
• (a) What are the issues that you need to
  address in your design?

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Sample Question

• Problem
• Give an architectural description in CSP for
  the following architecture

M0
M2
M5
F1
F2
O1
M4
M1
F3
F4
M3
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Sample Question

• Problem
• We have used cohesion and coupling to compare
  different software architectures. In this
  problem, we introduce a new metric, called
  Component Structural Complexity (CSC). The
  structural complexity of a component i is defined
  as follows
• CSC(i) f2out(i),
• Where fout(i) is the number of components
  immediately subordinate to the component i, that
  is, the number of components directly invoked by
  component i
• Design a system structural complexity (SSC)
  metric for the whole system using CSC metric,
  assuming you have a system of n components
• Measure SSC for pipeline and layered
  architectures.
• Compare SSC metric to coupling and cohesion.

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Sample Question

• Problem
• (a) Describe why you would use design patterns
  in your application.
• (b) Give an example of a design pattern and
  show how you would use it for a specific
  application. State clearly your application.

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Sample Questions Different Paradigms

• What the major design decisions you need to
  consider for
• Object-oriented programming
• Requirements of OOP
• Polymorphism
• Class Instance Record (CIR)
• FP
• Requirements of FP
• Be familiar with Scheme be able to understand
  scheme code
• LP
• Requirements of LP
• Resolution algorithm
• Unification
• Query processing
• Concurrency
• Requirements of concurrency.

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Sample Question

• Problem
• class A
• public
• int a
• virtual void what()
• virtual void who()
• class B
• public
• int b
• virtual void what
• class C public A, public B
• public
• int c
• virtual void what()
• virtual void who()
• virtual void dud()

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Sample Question

• Problem
• One of the programming language paradigms we
  have covered is logic programming.
• 1. Describe this paradigm and compare it to
  a programming language paradigm of your
  choice.
• 2. Give detailed description of the different
• parts of a logic program.
• 3. One of the drawbacks of logic programming
  is low performance. How would your enhance the
  efficiency of a logic programming compiler?

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Sample Question

• Problem
• You are asked to extend a procedural language
  to become an object-oriented (OO) language.
• (1) State the OO features that you need to
  add to your procedural language
• (2) Explain how you would implement each of
  the features in (1)

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Sample Question

• Problem
• Consider the following logic program
• mother (mary, sue).
• mother (mary, bill).
• mother (sue, nancy).
• mother (sue, jeff).
• mother (jane, ron).
• father (john, sue).
• father (john, bill).
• father (bob, nancy).
• father (bob, jeff).
• Father(bill,ron).
• Parent(A,B) - father(A,B).
• Parent (A,B) - mother(A,B).
• Grandparent(C,D) - parent(C,E), parent(E,D).
• Show the trace of the processing of the
  following queries
• ?- grandparent(Who, ron).
• Add a sibling relationship to the above program
  and answer the following question
• ?- sibling(sue, X).

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• G o o d L u c k