I am sending this assignment for the 5rd time, but in the others it is in the factory section is wrong. [Exception in thread "main" java.lang.NullPointerException at Factory.removeEmployee(Factory.java:49) at Test.main(Test.java:11) incorrect] I'm getting these errors.

and they sent the same code in all of them. Could you please write new code.

please help me and

n this homework, you will implement a factory simulator program with object-oriented approach. In the UML diagrams below, access (getter) and modifier (setter) methods are not shown for simplicity. However, you are supposed to implement these methods for each class as well.

1) Implement an Item class using the following UML diagram.

Item

- id: int

+ numberOfItems: int

+ Item(id: int)

An Item object represents an item generated by the employees working for the factory.

Data field id keeps the id of the Item object created.

Static data field numberOfItems keeps the number of item objects created.

An item is created with an id data field. o You have to use this keyword in the implementation of the constructor.

o In the constructor, you also need to increment numberOfItems data field.

o Consider the following example which demonstrates the creation of Item object.

Item item = new Item(10);

2) Implement a Payroll class using the following UML diagram.

Payroll

- workHour: int

-itemCount: int

+ Payroll(workHour: int, itemCount: int)

+ calculateSalary(): int

+ toString(): String

A Payroll object represents the payroll of the employees.

Data field workHour keeps the number of hours an employee has worked.

Data field itemCount keeps the number of items an employee has produced.

A Payroll object is created with a given workHour and itemCount.

o You have to use this keyword in the implementation of the constructor.

o Consider the following example which demonstrates the creation of Payroll object.

Payroll payroll = new Payroll(8,15);

o Here, the payroll will be created for the 8 hours of working and 15 produced items.

calculateSalary() method calculates salary of the employee according to the number of hours an employee has worked and the number of items s/he produced. For each hour an employee works, s/he earns 3 liras and for each item s/he produces s/he additionally earns 2 liras.

o As an example, an employee will earn 8*3=24 liras for the working hours and 15*2=30 liras for the items produced with the sample Payroll above; hence a total of 54 liras should be calculated.

toString() method returns a String containing information about the work hour and the item count of the payroll. An example string is as following:

o The work hour is 8 and the produced item count is 15.

3) Implement an Employee class using the following UML diagram.

Employee

- id: int

-name: String

-surname: String

-workHour: int

-speed: int

-items: Item[]

-payroll: Payroll

+ Employee(id: int, name: String, surname: String, workHour: int, speed: int)

+startShift(): Item[]

+endShift(): Payroll

+toString(): String

An Employee object represents an employee working for the factory.

Data field id keeps the id number of the Employee object created.

Data fields name and surname keeps the name and the surname of the employee, respectively.

Data field workHour keeps the number of hours an employee will work.

Data field speed keeps the number of items that the employee can produce in an hour.

Data field items array holds the items produced by the employee.

Data field payroll keeps the payroll of the employee.

An employee is created with an id, name, surname, workhour, and speed values.

o You have to use this keyword in the implementation of the constructor.

o Consider the following example which demonstrates the creation of Employee object.

Employee employee = new Employee(1, "Ahmet", "Yilmaz", 8, 3);

o Here, an employee has an id of 1, name of Ahmet, surname of Yilmaz, working hour of 8, and speed of 3 .Here, speed represents that the employee can produce 3 items in an hour.

startShift() method finds how many items this employee should produce according to speed and workHour values. After that, it creates appropriate number of items with randomly generated ids between 1-100 and put them into items array. It then returns items array.

endShift() method creates a Payroll object with employees work hour and the number of items s/he creates. It assigns this object to payroll data field. It then returns payroll object.

toString() method returns a String with employees id and the return value of the payroll objects toString() method. An example string is as following: o This is the employee with id 1 speed 3. The work hour is 8 and the produced item count is 24.

4) Implement a Storage class using the following UML diagram. Storage - capacity: int -Items: Item[] + Storage(capacity: int) +addItem(item: Item): void

A Storage object represents a storage area for the factory.

Data field id capacity keeps the capacity (the maximum number of items that can be stored) of the Storage object created.

Data fields items array keeps the items put inside the storage.

A storage is created with a given capacity value.

o You have to use this keyword in the implementation of the constructor.

o Consider the following example which demonstrates the creation of Storage object. Storage storage = new Storage(100);

addItem(item:Item) method adds the item passed as the parameter to the items data field. Note that you need to resize the items array for this.

5) Implement a Factory class using the following UML diagram.

Factory

- name: String

-employees: Employee[]

-storage: Storage

-payrolls: Payroll[]

-itemPrice: double

+ Factory(name: String, capacity: int, itemPrice: double)

+getRevenue(): double

+getPaidSalaries(): double

+addEmployee(employee: Employee): void

+removeEmployee(id: int): Employee

-addPayroll(payroll: Payroll): void

A Factory object represents a factory with employees.

Data field name represents the name of the factory.

Data field employees represents employees working for the factory.

Data field storage represents the storage area of the factory.

Data field payrolls represents the payrolls belonging to the employees.

Data field itemPrice represents the price for one item (Suppose that all items have the same price).

A factory is created with a given name, capacity, and itemPrice value.

o You have to use this keyword in the implementation of the constructor.

o In the constructor, you also need to create a Storage object with the given capacity and assign it to storage data field.

o Consider the following example which demonstrates the creation of Factory object. Factory factory = new Factory("My Factory", 100, 5);

getRevenue() method returns the revenue according to the number of items in the storage data field and itemPrice data field.

getPaidSalaries() method calculates the paid salaries of the employees according to the payrolls array. Note that you need to use calculateSalary() method of payroll objects in payrolls array.

addEmployee(employee:Employee) method adds an employee to the employees array.

o Note that you need to resize the employees array for this.

o Then, you need to call startShift() method of the newly added employee and add all the items returned from startShift() method to storage, using addItem(item:Item) method of storage data field.

removeEmployee(id:int) method removes the employee from employees array.

o If there are no employees, it prints an appropriate error message.

o If the employee with a given id is not found, it prints an appropriate error message.

o If the employee is found, it removes employee from the employees array.

Note that you need to resize the employees array for this.

o Then, you need to call endShift() method of the newly removed employee and call addPayroll(payroll:Payroll) method with the returned payroll by the endShift() method.

o At the end, you need to return the removed employee.

addPayroll(payroll:Payroll) method adds the payroll passed as the parameter to the payrolls data field. Note that you need to resize the payrolls array for this.

You are given a simple scenario (Test.java) to test your class implementations. Note that the output of the example test class is as the following:

There are no employees!

Employee does not exist!

This is the employee with id 1 speed 3. The work hour is 8 and the produced item count is 24.

This is the employee with id 2 speed 2. The work hour is 6 and the produced item count is 12.

This is the employee with id 3 speed 1. The work hour is 10 and the produced item count is 10.

Revenue: 230.0

Paid salaries: 164.0

Total item produced: 46

IMPORTANT NOTES 1) There might be other test cases too. Therefore, please pay attention to use the same class, method and variable names in your implementations. You are allowed to increase the number of methods in the classes; however, you cannot decrease the number of them. You are not allowed to use ArrayLists in the homework! You can only use Arrays.

2) Write a comment at the beginning of each program to explain the purpose of the program. Write your name and student ID as a comment. Include necessary comments to explain your actions.

3) You are allowed to use the materials that you have learned in lectures and labs. Do not use the ones that you have not learned in the course.

4) Please be sure that your programs run properly on any computer.

5) Your program will be tested with an auto-grader. So, it should take the inputs exactly the same in the sample runs and it should print the outputs exactly the same in the sample runs. Otherwise, your program may fail.

6) Your program should execute correctly for different test cases.

7) Please do not write any package name at the beginning of your code.

a) 5 Java source files: Item.java, Payroll.java, Employee.java, Storage.java, Factory.java.

b ) 5 Java class files: Item.class, Payroll.class, Employee.class, Storage.class, Factory.class.

10) You are responsible for making sure you are turning in the right file, and that it is not corrupted in anyway. We will not allow resubmissions if you turn in the wrong file, even if you can prove that you have not modified the file after the deadline.

11) Each student should submit his/her own homework. You can discuss with your peers about the homework, but you are not allowed to exchange codes or pseudocodes. This also applies to material found on the web. If some submitted homework assignments are found to be identical or suspected to be identical, all involved parties will get a grade of ZERO from all homework. You should submit your own work. In case of any forms of cheating or copying, both giver and receiver are equally culpable and suffer equal penalties. All types of plagiarism will result in FF grade from the course

PLEASE , I WILL BE VERY HAPPY IF YOU TRY TO WRITE A BEGINNING-LEVELS JAVA ( ECLIPSE ) CODEI WILL BE VERY HAPPY IF YOU TRY TO WRITE A BEGINNING-LEVELS JAVA ( ECLIPSE ) CODE AND PAY ATTENTON TO THE IMPORTANT NOTES .PLEASE PLEASE PLEASE don't use old codes and write new code. Because a program reads the assignments and if the codes get old I get zero. And just use what's written in the assignment (don't use super , try catch etc) Thank you very much in advance.

public class Test {

public static void main (String[] args) {

Factory myFactory = new Factory("My Factory", 100, 5);

Employee emp1 = new Employee(1, "Ahmet", "Yilmaz", 8, 3); Employee emp2 = new Employee(2, "Ayse", "Yildirim", 6, 2); Employee emp3 = new Employee(3, "Mehmet", "Kara", 10, 1);

myFactory.removeEmployee(123);

myFactory.addEmployee(emp1); myFactory.addEmployee(emp2); myFactory.addEmployee(emp3);

myFactory.removeEmployee(emp1.getId()); myFactory.removeEmployee(emp2.getId()); myFactory.removeEmployee(emp3.getId());

myFactory.removeEmployee(123);

System.out.println(emp1.toString()); System.out.println(emp2.toString()); System.out.println(emp3.toString());

System.out.println("Revenue: " + myFactory.getRevenue()); System.out.println("Paid salaries: " + myFactory.getPaidSalaries());

System.out.println("Total item produced: " + Item.numberOfItems); } }