This assignment aims to practice implementing and using the Composite Design Pattern. You

will extend the Employee hierarchy by adding a new leaf classes, implementing new

functionality, and creating a test program to exercise your code.

Reference for Lab rarr

Part $1$: Adding a new Employee type

$1\mathrm{.}1.$ Define a new leaf class, Intern, that implements the Employee interface.

$1\mathrm{.}2.\mathrm{.}1.$ Define a new leaf class,

$,$ that implements the

interface. Attributes

are empld, Department, and Name

$1\mathrm{.}3.$ The Intern $\text{'}$s position should always be "Intern." This should be set inside the Intern

class and not be modifiable from outside. The Attributes of the class are Name, position, and

universityAttended.

$1\mathrm{.}4.$ Implement the showEmployeeDetails$()$ method to print the details of the Intern.

$1\mathrm{.}5$ Implement the showEmployeeDetails$()$ method to print the details of the Manager $.$

Part $2$: Adding new functionality

$2\mathrm{.}1.$ Add a countEmployees$()$ method to the CompanyDirectory class. This method should

return the total number of employees in the directory.

Part $3$: Testing your code

$3\mathrm{.}1.$ Create a CompanyDirectory for the software department and add two Developer

instances, one Manager instance, and one instance to it$.$

$3\mathrm{.}2.$ Call showEmployeeDetails$()$ on the software department directory to print the details of

all the employees.

$3\mathrm{.}3.$ Call

on the software department directory and print the result.

Submission Guidelines

Please submit the $.$java files that include your code $(.$zip file if your code.$)$ and a screenshot of

the code running. Please ensure that your code compiles and runs without errors before

submitting.

Composite design pattern:

Code:

package CompositePatternDemo;

$//$Component

interface Employee $\{$

void showEmployeeDetails$()$;

$\}$

The Employee interface defines a common operation, showEmployeeDetails$(),$ which is to

be implemented by all objects in the composition. All employees, whether they are a simple

developer or a composite directory, will have this operation.

package CompositePatternDemo;

import java.util.ArrayList;

import java.util.List;

$//$Composite

class CompanyDirectory implements Employee $\{$

private List employeeList $=$ new ArrayList$()$;

@Override

public void showEmployeeDetails$()\{$

for $($Employee emp : employeeList$)\{$

emp.showEmployeeDetails$()$;

$\}$

$\}$

public void addEmployee$($Employee emp$)\{$

employeeList.add$($emp$)$;

$\}$

public void removeEmployee$($Employee emp$)\{$

employeeList.remove$($emp$)$;

$\}$

$\}$

package CompositePatternDemo;

$//$Leaf

class Developer implements Employee $\{$

private String name;

private long empId;

private String position;

public Developer$($long empId, String name, String position$)\{$

this.empId $=$ empId;

this.name $=$ name;

this.position $=$ position;

$\}$

@Override

public void showEmployeeDetails$()\{$

System.out.println$("$Developer ID: $"+$ empId $+"$ Name: $"+$ name $+"$

$\}$

$\}$

Driver:

package CompositePatternDemo;

public class CompositeDriver $\{$

public static void main$($String$[]$ args$)$

$\{$

Employee dev$1=$ new Developer$(100,$ "Fred Flintstone", "Pro Develop

Employee dev$2=$ new Developer$(101,$ "Bart Simpson", "Developer"$)$;

CompanyDirectory engDirectory $=$ new CompanyDirectory$()$;

engDirectory.addEmployee$($dev$1)$;

engDirectory.addEmployee$($dev$2)$;

engDirectory.showEmployeeDetails$()$;

$\}$

$\}$

$16$