Modify many files, including Hints.md, to adapt them to the new exercise without streams.

Author: josealonso

exercises/concept/tim-from-marketing-2/.docs/hints.md

@@ -1,9 +1,10 @@
 # Hints
 
+## 1. Get an employee by ID
 
-## 1.- Print the name of all the employees
-WIP
+- This method returns an `Optional<Employee>` object, not an `Employee` one.
 
+## 2. Return the name and department of a given employee in a certain format 
 
-## 2.- Print the name and department of a given employee
-WIP
+- You can call the method `getEmployeeById(int)` to get the employee.
+- Remember the syntax of the `ifPresentOrElse()` method.

exercises/concept/tim-from-marketing-2/.docs/instructions.md

@@ -1,30 +1,24 @@
 # Instructions
 
-In this exercise you will be writing code to print all the names of the factory employees.
+In this exercise you will be writing code to retrieve the factory employees.
 Employees have an ID, a name and a department name, like in the [tim-from-marketing](/exercises/concept/tim-from-marketing) exercise. 
-Assume that the ID of the first employee is 0, the ID of the second employee is 1, and so on. The three fields of an employee may be empty, that's why they are declared as Optional<T> types.
-The class constructor receives a parameter of type List<Optional<Employee>>, which is populated in the tests.
+The first field of an employee is always an integer number, but the name and the department name may be empty or null.
+The class constructor receives a parameter of type List<Employee>, which is populated in the tests.
+You will be writing two methods: `getEmployeeById(int)` and `getEmployeeDetailsById(int)`.
 
-## 1.- Print the names of all the employees
+## 1. Get an employee by ID
 
-Implement the `printAllEmployeesNames()` method to print the names of all the employees, together with their id. If the employee does not exist, print "[id] - No employee found".
+Implement the `getEmployeeById(int)` method so that it returns an Optional<Employee> object. 
+If the employee does not exist, returns an empty Optional instance.
 
-```java
-"
-1 - Tim
-2 - Bill
-3 - Steve
-4 - No employee found
-5 - Charlotte
-"
-```
+## 2. Return the name and department of a given employee in a certain format
 
-## 2.- Print the name and department of a given employee
-
-Implement the `printEmployeeNameAndDepartmentById(id)` method to print the name and department of a given employee, together with their id. If the employee does not exist, print "[id] - No employee found". You will have to call the method `getEmployeeById(int employeeId)`, which returns an Optional<Employee> and it's already defined.
+Implement the `getEmployeeDetailsById(int)` method to return a string containing the id, the name and 
+the department of a given employee:
 
 ```java
-printEmployeeNameAndDepartmentById(1) => "1 - Tim - Marketing"
-printEmployeeNameAndDepartmentById(3) => "3 - Steve - Engineering"
-printEmployeeNameAndDepartmentById(4) => "4 - This employee does not exist"
+getEmployeeDetailsById(1) => "1 - Tim - Marketing"
+getEmployeeDetailsById(3) => "3 - Steve - Engineering"
 ```
+
+If the employee does not exist or is null, it returns `No employee found for id: [id]`.

exercises/concept/tim-from-marketing-2/.meta/src/reference/java/Employee.java

@@ -31,12 +31,23 @@ public boolean equals(Object o) {
         if (o == null || getClass() != o.getClass())
             return false;
         Employee employee = (Employee) o;
-        return id == employee.id &&
-                Objects.equals(name, employee.name) && Objects.equals(department, employee.department);
+        return id == employee.id && Objects.equals(name, employee.name)
+                && Objects.equals(department, employee.department);
     }
 
     @Override
     public int hashCode() {
         return Objects.hash(id, name, department);
     }
+
+    @Override
+    public String toString() {
+        return "Employee{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", department='" + department + '\'' +
+                '}';
+    }
+
 }
+

exercises/concept/tim-from-marketing-2/.meta/src/reference/java/EmployeeService.java

@@ -0,0 +1,47 @@
+import java.util.List;
+import java.util.Optional;
+import java.util.Objects;
+
+class EmployeeService {
+
+    // This list is populated in the tests
+    private List<Employee> employeesList;
+
+    public EmployeeService(List<Employee> listOfEmployees) {
+        employeesList = listOfEmployees;
+    }
+
+    public Optional<Employee> getEmployeeById(int employeeId) {
+        for (Employee employee : employeesList) {
+            if (Objects.equals(employee.getId(), employeeId)) {
+                return Optional.of(employee);
+            }
+        }
+        return Optional.empty();
+    }
+
+    public String getEmployeeDetailsById(int employeeId) {
+        Optional<Employee> nullableEmployee = getEmployeeById(employeeId);
+        StringBuilder stringBuilder = new StringBuilder();
+        nullableEmployee.ifPresentOrElse(
+                employee1 -> {
+                    Optional.ofNullable(employee1.getName())
+                            .ifPresentOrElse(name -> stringBuilder.append(employeeId).append(" - ")
+                                    .append(employee1.getName()).append(" - ")
+                                    .append(employee1.getDepartment()),
+                            () -> {
+                                stringBuilder.append("No employee found for id: ").append(employeeId);
+                            });
+                },
+                () -> {
+                    stringBuilder.append("That id does not exist: ").append(employeeId);
+                });
+        return stringBuilder.toString();
+    }
+}
+
+
+
+
+
+

exercises/concept/tim-from-marketing-2/.meta/src/reference/java/Main.java

@@ -1,5 +1,4 @@
 import java.util.Objects;
-import java.util.Optional;
 
 class Employee {
     private final int id;  
@@ -12,16 +11,16 @@ public Employee(int id, String name, String department) {
         this.department = department;
     }
 
-    public Optional<Integer> getNullableId() {
-        return Optional.ofNullable(id);
+    public int getId() {
+        return id;
     }
 
-    public Optional<String> getNullableName() {
-        return Optional.ofNullable(name);
+    public String getName() {
+        return name;
     }
 
-    public Optional<String> getNullableDepartment() {
-        return Optional.ofNullable(department);
+    public String getDepartment() {
+        return department;
     }
 
     @Override
@@ -37,4 +36,13 @@ public boolean equals(Object o) {
     public int hashCode() {
         return Objects.hash(id, name, department);
     }
+
+    @Override
+    public String toString() {
+        return "Employee{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", department='" + department + '\'' +
+                '}';
+    }
 }

exercises/concept/tim-from-marketing-2/src/main/java/Employee.java

@@ -1,34 +1,51 @@
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.Optional;
 
 class EmployeeService {
 
-    //  This list is populated in the tests
-    private List<Optional<Employee>> nullableEmployeesList = new ArrayList<>();
+    private List<Employee> employeesList;
 
-    public EmployeeService(List<Optional<Employee>> listOfEmployees) {
-        nullableEmployeesList = listOfEmployees;
+    public EmployeeService(List<Employee> listOfEmployees) {
+        //  This list is populated in the tests
+        employeesList = listOfEmployees;
     }
 
     public Optional<Employee> getEmployeeById(int employeeId) {
-        return nullableEmployeesList
-                .stream()
-                .flatMap(employee -> employee.stream())
-                .filter(employee -> employee.getNullableId()
-                        .map(id -> id == employeeId)
-                        .orElse(false))
-                .findFirst();
+        for (Employee employee : employeesList) {
+            if (Objects.equals(employee.getId(), employeeId)) {
+                return Optional.of(employee);
+            }
+        }
+        return Optional.empty();
     }
 
-    public String printAllEmployeesNames() {
-        throw new UnsupportedOperationException(
-        "Please implement the EmployeeService.printAllEmployeesNames() method");
+    public String getEmployeeDetailsById(int employeeId) {
+        Optional<Employee> nullableEmployee = getEmployeeById(employeeId);
+        StringBuilder stringBuilder = new StringBuilder();
+        nullableEmployee.ifPresentOrElse(
+                employee1 -> {
+                    Optional.ofNullable(employee1.getName())
+                            .ifPresentOrElse(name -> stringBuilder.append(employeeId).append(" - ")
+                                            .append(employee1.getName()).append(" - ")
+                                            .append(employee1.getDepartment()),
+                                    () -> {
+                                        stringBuilder.append("No employee found for id: ").append(employeeId);
+                                    });
+                },
+                () -> {
+                    stringBuilder.append("No employee found for id: ").append(employeeId);
+                });
+        return stringBuilder.toString();
     }
 
-    public String printEmployeeNameAndDepartmentById(int employeeId) {
-        throw new UnsupportedOperationException(
-        "Please implement the EmployeeService.printEmployeeNameAndDepartmentById(id) method");
-    }
+//    public Optional<Employee> getEmployeeById(int employeeId) {
+//        throw new UnsupportedOperationException("Please implement this method");
+//    }
+//
+//    public String getEmployeeDetailsById(int employeeId) {
+//        throw new UnsupportedOperationException("Please implement this method");
+//    }
 
 }