Download WholePartPattern

Software Design Laboratory
Dept of MCA, AMCEC
10. Whole Part Pattern (Structural Decomposition)
Intent: The Whole Part design pattern helps with the aggregation of components that
together form a semantic unit. An aggregation component, the Whole, encapsulates its
constituent components, the parts, organizes their collaboration, and provides a common
interface to its functionality. Direct access to the parts is not possible.
Structure:
Participant Classes:
Client: The task of a client is to access only the services performed by Whole.
Whole: The responsibility of the Whole is to aggregate several smaller objects;
Provides services built on top of part object; Acts as a wrapper around its constituent parts.
Part: Represents a particular object and its services
Example: Creation of the list of professors working in a University
Pattern Instance
Client: Client
Whole: University
Part: Professor
Use Case Diagram:
System
<<include>>
doTask
Client
University
Professor
Software Design Laboratory
Dept of MCA, AMCEC
Sequence Diagram:
: University
: Professor
: Client
1 : doTask()
2 : addUniversity()
sd Add Professors3 : addProfessorList()
4 : addProfessor()
sd showProfessors
5 : showProfessorList()
6 : getProfessor
7 : displayProfessorList
Class Diagram:
WholePart
University
-uName: String
-profList: ArrayList<Professor>
Client
+doTask()
+main()
1
1
+setUName(String): void
+getUName(): String
+addUniversity(String): void
+addProfList(int, String): void
+showProfList(): void
Professor
1
1..*
-profId: int
-profName: String
+setProfId(int): void
+getProfId(): int
+setProfName(String): void
+getProfName(): String
+addProfessor(int, String): void
Software Design Laboratory
Dept of MCA, AMCEC
Collaboration Diagram:
1 : doTask()
3 : addProfessorList()
2 : addUniversity()
: University
4 : addProfessor()
5 : showProfessorList()
: Client
6 : getProfessor
7 : displayProfessorList
Activity Diagram:
Add University
Add Professor List
Option = 1
Option=2
Create Professor List
Option=3
Add Professor
Show Professor List
Show Professor List
Get Professor
Java Code:
//Client.java
package WholePart;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Client {
public static void main(String[] args)throws IOException {
Client client =new Client();
client.doTask();
}
public void doTask()throws IOException {
: Professor
Software Design Laboratory
Dept of MCA, AMCEC
BufferedReader br=new BufferedReader(new
InputStreamReader(System.in));
System.out.print("Enter the name of the university: ");
String univ=br.readLine();
University newUniv=new University();
newUniv.addUniversity(univ);
int opt=0;
do{
System.out.println("\t\tMenu\n\t(1)--Add Professor
\n\t(2)--Show Professor List \n\t(3)--Exit\n");
System.out.print("Enter the option: ");
opt=Integer.parseInt(br.readLine());
switch(opt){
case 1:
System.out.print("Enter the professor id: ");
int id=Integer.parseInt(br.readLine());
System.out.print("Enter the professor name: ");
String name=br.readLine();
newUniv.addProfList(id, name);
break;
case 2:
newUniv.showProfList();
break;
case 3:
break;
default:System.out.print("Invalid option.");
}
}while(opt!=3);
}
}
//University.java
package WholePart;
import java.util.ArrayList;
public class University {
private String uName;
private ArrayList<Professor> profList=new ArrayList<Professor>();
public void setUName(String univ) {
uName=univ;
}
public String getUName() {
return uName;
}
Software Design Laboratory
Dept of MCA, AMCEC
public void addUniversity(String name){
setUName(name);
}
public void addProfList(int id, String name){
Professor newProf = new Professor();
newProf.addProfessor(id,name);
profList.add(newProf);
}
public void showProfList(){
if(profList.size()==0)
System.out.println("Sorry list is empty");
else{
System.out.println("Professorlist in - "+this.getUName());
for(Professor prof:profList)
System.out.println("Professor Id is:" +
prof.getProfId()+" Professor name is: "+prof.getProfName());
}
}
}
//Professor.java
package WholePart;
public class Professor {
private int profId;
private String profName;
public int getProfId() {
return profId;
}
public void setProfId(int profId) {
this.profId = profId;
}
public String getProfName() {
return profName;
}
public void setProfName(String profName) {
this.profName = profName;
}
public void addProfessor(int id,String name){
setProfId(id);
setProfName(name);
}
}
Output:
Enter the name of the university: VTU
Menu
(1)--Add Professor
(2)--Show Professor List
(3)--Exit