Software Engineering Implementation Lecture 3 ASPI8-4 Anders P. Ravn, Feb 2004.

Software EngineeringImplementation

Lecture 3

ASPI8-4

Anders P. Ravn, Feb 2004

Overview• Summary – Documents, Domains

• Module Specification - Java1. Class, object (variable)

2. Generalization

3. Association

4. Dependency

5. Interface

6. Package

7. Active Class Task (thread)

Documents -51.1. Requirements SpecificationRequirements Specification

1.1 System Definition1.1 System Definition

1.2 Problem Domain Structure1.2 Problem Domain Structure

1.3 Application Domain Structure

1.3.1 Use Cases

1.3.2 Functions

1.3.3 Interfaces

1.4 Acceptance Test Specification

2. Architecture

2.1 Criteria

2.X Module Interfaces

2.T Integration Test Specification

Documents -6!

1. Requirements Specification

2. Architecture

3. Modules

4. Implementation

5. Test

Activities: application domain analysis

Usage

Functions

Systemdefinition

and ProblemDomainmodels

Interfaces

ApplicationDomainModel

andSoftware

Requirements

Design

Problem Domain Application Domain

Model

Model*

Use case Actor

InterfaceSystem

Class and Object

Class name

attributes

methods

Object: Class

1 *

Java class class C {

public boolean b;

protected char c;

private byte i8; C cl;

public int method(int x, C y)

{if (b) return y.method(7,c1);

else return i8; }

public C(long count)

{if (count > 0)

c1=new C(count-1); }

}

Java variables/objects

boolean b;

character c;

byte i8; short i16; int i32; long i64;

float ieee32f; double ieee64f;

C xx = new C(5);

int[] ia = new int[250];

C[] ca = new C[10];

ca[0] = new C(ia[249]);

Java class class C {

public boolean b;

protected char c;

private byte i8; C cl;

public C(long count)

{if (count > 0)

c1=new C(count-1); }

public int method(int x, C y)

{if (b) return y.method(7,c1);

else return i8; }

}

Moduleclass M {

public bool b; ...

public int method(int x, C y)

{if(b)return ...;}

public M(boolean b)

{ super(); this.b = b;}

public M() {this(false);}

}; ...

M module1= new M(true), module2= new M();

Module Specification

abstract class MSpec {

public boolean b;

abstract int method(int x, C y);

}

Module Implementationclass M extends Mspec {

private byte i8; int i16; ...

public int method(int x, C y)

{if(b)return ...;}

public M(boolean b)

{ super(); this.b = b;}

public M() {this(false);}

};...

M module1= new M(true), module2= new M();

Generalization

Superclass

Subclass

Java extends

class superclass {

...

};

class subclass extends superclass {

...

}

Cluster (package)

related classes

<<cluster>> name

Java package

package driverspec; source1

abstract class DSpec{ ... };

...

source2

package drivers

import driverspec.*;

public class D extends DSpec {...};

...

Aggregation

the whole

the parts

[arity]

aggregation – by inclusionabstract class WholeSpec {

protected P1 p1; P2 p2;

Ps[] p;

};

...

class Whole extends WholeSpec {

public Whole(int p_arity)

{p1= new P1(); p2= new P2();

p = new Ps[p_arity]; ...}

}

aggregation – by referenceabstract class WholeSpec {

protected P1 p1; P2 p2;

Ps[] p;

};

...

class Whole extends WholeSpec {

public Whole(P1 p1, P2 p2, Ps[] p)

{this.p1= p1; this.p2= p2;

p = new Ps[p.length]; ...}

}

Association

[name]A B

[arity] [arity]

association – by referenceclass ASpec {

protected B b;

};...

class A extends ASpec {

public A(B b) {this.b = b;}

public void setb(B b) {this.b = b;}

}...

A a; B b;

a = new A(nil); b = new B(a); a.setb(b);

Interface Class and Dependency

IRow

Image Hydraulics

use

<<interface>>IRow

userealise

Java interface

interface IRow {

// methods only !

}

class Image implements IRow {

...

}

IRow

Image

realize

Start and Parameters

class System {

public static final int MAX = 10;

public static int ACTUAL;

public static void main(String[] args)

{ int a = Integer.parseInt(args[0]);

if (a > MAX || a < 0) a = MAX;

ACTUAL = a;}

}

Exceptions

class BadData extends Exception {

BadData(String s)

{super(”Bad data”+s+”\n”);}

};

class Reader {

public void read(Data d) throws BadData

{ ... throw new BadData(”!!!”); ...}

}

Exception Handlers

public void someMethod()

{ Data x;

Reader r = new Reader();

try { r.read(x); ...

} catch (BadData b) { ...

...

} finally { ... }

}

Maintaining Documentation

• Documentation comments

• Libraries

• Module test

• Applets

• API, Swing

C++ class C {

public boolean b;

protected char c;

private byte i8; C *cl;

public C(long count)

{if (count > 0)

c1=new C(count-1); }

public int method(int x, C *y)

{if (b) return y->method(7,c1);

else return i8; }

}