Finish the task CSV Writer

pom.xml

@@ -21,6 +21,11 @@
             <version>1.18.34</version>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>net.datafaker</groupId>
+            <artifactId>datafaker</artifactId>
+            <version>2.3.0</version>
+        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>

src/main/java/org/writer/Main.java

@@ -1,7 +1,30 @@
 package org.writer;
 
+import net.datafaker.Faker;
+import org.writer.model.Months;
+import org.writer.model.Person;
+import org.writer.model.Student;
+
+import java.util.ArrayList;
+import java.util.List;
+
 public class Main {
     public static void main(String[] args) {
-        System.out.println("Hello world!");
+        Faker faker = new Faker();
+        WritableImpl writableImpl = new WritableImpl();
+
+        List<Student> students = new ArrayList<>();
+        for (int i = 0; i < 5; i++) {
+            students.add(new Student(faker.name().firstName(), List.of(faker.size().adjective(), faker.size().adjective())));
+        }
+        writableImpl.writeToFile(students, "output.csv");
+
+
+        List<Person> persons = new ArrayList<>();
+        for (int i = 0; i < 5; i++) {
+            persons.add(new Person(faker.name().firstName(), faker.name().lastName(), 22, Months.APRIL, 1094));
+        }
+        writableImpl.writeToFile(persons, "output.csv");
+
     }
 }

src/main/java/org/writer/WritableImpl.java

@@ -0,0 +1,86 @@
+package org.writer;
+
+import org.writer.exception.AccessFileException;
+import org.writer.exception.InvalidDataException;
+
+import java.io.FileWriter;
+import java.io.IOException;
+import java.lang.reflect.Field;
+import java.util.Collection;
+import java.util.List;
+import java.util.logging.Logger;
+import java.util.stream.Collectors;
+
+/**
+ * Класс реализации записи данных в файл в формате CSV
+ */
+
+public class WritableImpl implements Writable {
+    private final Logger logger = Logger.getLogger(WritableImpl.class.getName());
+    private final StringBuilder stringBuilder = new StringBuilder();
+
+
+    /**
+     * Вадидация входных даннных
+     * @param data - список обьектов
+     * @param fileName - имя файла для записи
+     * @throws InvalidDataException - бросает исключение
+     */
+    @Override
+    public void writeToFile(List<?> data, String fileName) {
+            if (validateMethod(data, fileName)) {
+                try (FileWriter fw = new FileWriter(fileName))
+                {
+                    for (Object object : data) {
+                        Class<?> aClass = object.getClass();
+                        Field[] fields = aClass.getDeclaredFields();
+                        for (Field field : fields) {
+                            field.setAccessible(true);
+                            Object valueField = field.get(object);
+                            resolveFieldClass(valueField);
+                        }
+                    }
+                    if (!stringBuilder.isEmpty()) {
+                        stringBuilder.setLength(stringBuilder.length() - 1);
+                    }
+                    fw.write(stringBuilder.toString());
+                } catch (IllegalAccessException e) {
+                    throw new InvalidDataException("Invalid data!");
+                } catch (IOException e) {
+                    throw new AccessFileException("Access file error!");
+                }
+            } else {
+                throw new InvalidDataException("Invalid data!");
+            }
+    }
+
+    /**
+     * Вадидация входных даннных
+     * @param data - список обьектов
+     * @param fileName - имя файла для записи
+     */
+    private boolean validateMethod(List<?> data, String fileName) {
+        if (data == null || fileName == null) {
+            logger.warning("Data or File Name is null!");
+            return false;
+        } else if (data.isEmpty() || fileName.isEmpty()) {
+            logger.warning("Data or File Name is empty!");
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Проверка типа поля и заполнение stringbuilder
+     * @param valueField - поле обьекта
+     */
+    private void resolveFieldClass (Object valueField) {
+        if (valueField instanceof Collection) {
+            String collect = ((Collection<?>) valueField).stream().map(value -> value.toString()).collect(Collectors.joining("|"));
+            stringBuilder.append(collect).append(',');
+        } else {
+            stringBuilder.append(valueField).append(',');
+        }
+    }
+}

src/main/java/org/writer/exception/AccessFileException.java

@@ -0,0 +1,10 @@
+package org.writer.exception;
+
+public class AccessFileException extends RuntimeException {
+    public AccessFileException(String message) {
+        super(message);
+    }
+    public AccessFileException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/org/writer/exception/InvalidDataException.java

@@ -0,0 +1,11 @@
+package org.writer.exception;
+
+public class InvalidDataException extends RuntimeException {
+
+    public InvalidDataException(String message) {
+        super(message);
+    }
+    public InvalidDataException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/org/writer/model/Months.java

@@ -1,5 +1,9 @@
 package org.writer.model;
 
+/**
+ * Enum с именами месяцев в году.
+ */
+
 public enum Months {
     JANUARY,
     FEBRUARY,

src/main/java/org/writer/model/Person.java

@@ -4,19 +4,26 @@
 import lombok.Builder;
 import lombok.Data;
 
+/**
+ * Класс сущности Person
+ */
+
 @Data
 @Builder
 @AllArgsConstructor
 public class Person {
-
+    /** Поле имя */
     private String firstName;
 
+    /** Поле фамилия */
     private String lastName;
 
+    /** Поле дата рождения */
     private int dayOfBirth;
 
+    /** Поле месяц рождения */
     private Months monthOfBirth;
 
+    /** Поле год рождения */
     private int yearOfBirth;
-
 }

src/main/java/org/writer/model/Student.java

@@ -6,12 +6,16 @@
 
 import java.util.List;
 
+/**
+ * Класс сущности Student
+ */
+
 @Data
 @Builder
 @AllArgsConstructor
 public class Student {
-
+    /** Поле имя */
     private String name;
-
+    /** Поле счета, представляет из себя список String */
     private List<String> score;
 }

src/test/java/UnitTests/CSVWriterTest.java

@@ -0,0 +1,86 @@
+package UnitTests;
+
+
+import net.datafaker.Faker;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.writer.WritableImpl;
+import org.writer.exception.InvalidDataException;
+import org.writer.model.Months;
+import org.writer.model.Person;
+import org.writer.model.Student;
+
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+class CSVWriterTest {
+    private final Faker faker = new Faker();
+    private final  WritableImpl writable = new WritableImpl();
+    private final  List<Person> persons = new ArrayList<>();
+    private final  List<Student> students = new ArrayList<>();
+    private final String fileName = "output.csv";
+
+
+    @BeforeEach
+    void setUp() {
+        for (int i = 0; i < 5; i++) {
+            persons.add(new Person(faker.name().firstName(), faker.name().lastName(), 22, Months.APRIL, 1094));
+        }
+        persons.add(new Person("Egor", "Fillipov", 22, Months.APRIL, 1094));
+
+
+        for (int i = 0; i < 5; i++) {
+            students.add(new Student(faker.name().firstName(), List.of(faker.size().adjective(), faker.size().adjective())));
+        }
+        students.add(new Student("Egor", List.of("129", "200")));
+    }
+
+    @AfterEach
+    void tearDown() {
+        persons.clear();
+        students.clear();
+    }
+
+
+    @Test
+    void validPersonsWriteTest() throws IOException {
+        writable.writeToFile(persons, fileName);
+        Assertions.assertDoesNotThrow(() -> {});
+        FileReader fileReader = new FileReader(fileName);
+        BufferedReader bufferedReader = new BufferedReader(fileReader);
+        String s = bufferedReader.readLine();
+        Assertions.assertNotNull(s);
+        Assertions.assertTrue(s.contains("Egor"));
+    }
+
+    @Test
+    void validStudentsWriteTest() throws IOException {
+        writable.writeToFile(students, fileName);
+        Assertions.assertDoesNotThrow(() -> {});
+        FileReader fileReader = new FileReader(fileName);
+        BufferedReader bufferedReader = new BufferedReader(fileReader);
+        String s = bufferedReader.readLine();
+        Assertions.assertNotNull(s);
+        Assertions.assertTrue(s.contains("Egor"));
+    }
+
+    @Test
+    void invalidPersonsWriteTest() {
+        Assertions.assertThrows(InvalidDataException.class, () -> writable.writeToFile(null, fileName));
+    }
+
+    @Test
+    void invalidStudentsWriteTest() {
+        Assertions.assertThrows(InvalidDataException.class, () -> writable.writeToFile(null, fileName));
+    }
+
+    @Test
+    void invalidFileNameTest() {
+        Assertions.assertThrows(InvalidDataException.class, () -> writable.writeToFile(persons, null));
+    }
+}