Second

src/org/university/core/Account.java

+package org.university.core;
+
+public class Account {
+    private Employee employee;
+    private int balance;
+
+    public Account(Employee employee) {
+        this.employee = employee;
+        balance = 0;
+    }
+
+    public void checkout(double income){
+        balance += income;
+    }
+
+    public Employee getEmployee() {
+        return employee;
+    }
+
+    public double getBalance() {
+        return balance;
+    }
+}

src/org/university/core/AccountingManagement.java

+package org.university.core;
+
+import java.util.ArrayList;
+
+public class AccountingManagement {
+    private ArrayList<Account> accounts;
+    private ArrayList<Statement> transactions;
+
+    public AccountingManagement() {
+        this.accounts = new ArrayList<>();
+        this.transactions = new ArrayList<>();
+    }
+
+    public void addAccount(Account account)
+    {
+        this.accounts.add(account);
+    }
+    public void settle()
+    {
+        for (int i = 0 ; i < accounts.size(); i++)
+        {
+            accounts.get(i).checkout(accounts.get(i).getEmployee().calCurrentIncome() + accounts.get(i).getEmployee().getBasicIncome());
+            transactions.add(new Statement(accounts.get(i).getEmployee().calCurrentIncome() + accounts.get(i).getEmployee().getBasicIncome() , accounts.get(i).getEmployee()));
+        }
+    }
+
+    public ArrayList<Statement> getTransactions() {
+        return transactions;
+    }
+}

src/org/university/core/Employee.java

@@ -6,6 +6,7 @@ public abstract class Employee extends Person {
     protected ArrayList<Statement> bankStatements;
     protected String position;
     protected double basicIncome;
+    protected double requiredIncome;
 
     public Employee(String firstName, String lastName, String id, int joiningYear, Department department, String position, double basicIncome) {
         super(firstName, lastName, id, joiningYear, department);
@@ -31,6 +32,10 @@ public abstract class Employee extends Person {
         this.basicIncome = basicIncome;
     }
 
+    public double getBasicIncome() {
+        return basicIncome;
+    }
+
     public abstract double calCurrentIncome();
     public abstract Boolean isPromotable();
 }

src/org/university/core/Professor.java

@@ -31,6 +31,7 @@ public class Professor extends Employee{
 
     public double calCurrentIncome()
     {
+        return requiredIncome;
     }
 
     public Boolean isPromotable()

src/org/university/core/ServiceEmployee.java

@@ -6,9 +6,10 @@ public class ServiceEmployee extends Employee{
     }
     public double calCurrentIncome()
     {
+        return requiredIncome;
     }
     public Boolean isPromotable()
     {
-        
+
     }
 }