feat: add class FileWriter to append data to file

app/src/main/java/ru/project/datasource/DataSource.java

@@ -5,5 +5,5 @@ import ru.project.collection.MyList;
 
 
 public interface DataSource {
-    MyList<Student> fill(int size);
+    MyList<Student> create();
 }

app/src/main/java/ru/project/datasource/FileDataSource.java

@@ -9,6 +9,7 @@ import java.nio.file.Paths;
 import java.util.stream.Collector;
 import ru.project.student.Student;
 import ru.project.collection.MyList;
+import ru.project.collection.MyLinkedList;
 
 public class FileDataSource implements DataSource{
     private String fileName;
@@ -22,16 +23,16 @@ public class FileDataSource implements DataSource{
     }
 
     @Override
-    public MyList<Student> fill(int size) {
-        Path path = Paths.get(fileName);
+    public MyList<Student> create() {
+        Path path = Paths.of(fileName);
         try(var lines = Files.lines(path)){
-            return lines.skip(1)
-                    .limit(size)
+            return lines
+                    //.skip(1)
                     .map(e -> StringParser.parseString(e))
                     .filter(e -> !(e == null))
-                    .collect(Collector.of(MyList::new,
-                            MyList::add,
-                            (left, right) -> left.addAll(right)));
+                    .collect(Collector.of(MyLinkedList::new,
+                            MyLinkedList::add,
+                            (left, right) -> left;
         }catch(FileNotFoundException e){
             System.out.println("File not found.");
             return null;

app/src/main/java/ru/project/datasource/FileWriter.java

@@ -0,0 +1,36 @@
+package ru.project.datasource;
+
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import ru.project.student.Student;
+import ru.project.collection.MyList;
+import ru.project.collection.MyLinkedList;
+import ru.project.collection.Iterator;
+
+public class FileWriter {
+    private Path path;
+
+    public FileWriter(String absolutePath) {
+        this.path = Path.of(absolutePath);
+    }
+
+    public void write(MyList<Student> iist){
+        //int sizeOfCollection = list.size();
+        try (BufferedWriter writer = Files.newBufferedWriter(
+                path,
+                StandardOpenOption.CREATE,
+                StandardOpenOption.APPEND
+        )) {
+            Iterator iterator = list.getIterator();
+            while (iterator.hasNext()){
+                writer.write(iterator.next().toFileString());
+                writer.newLine();
+            }
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

app/src/main/java/ru/project/datasource/ManualDataSource.java

@@ -3,11 +3,25 @@ package ru.project.datasource;
 import java.util.Scanner;
 import ru.project.student.Student;
 import ru.project.collection.MyList;
+import ru.project.collection.MyLinkedList;
 
 public class ManualDataSource implements DataSource{
+    private int size;
+    private MyList<StudentBuffer> bufferMyList = new MyLinkedList<>();
+
+    public ManualDataSource(int size) {
+        this.size = size;
+    }
+
+    public boolean setStudent(
+            int index,
+            String groupNumber,
+            double averageGrade,
+            int recordBookNumber
+    ){}
     @Override
-    public MyList<Student> fill(int size) {
-        MyList<Student> result = new MyList<>();
+    public MyList<Student> create() {
+        MyList<Student> result = new MyLinkedList<>();
         String strToParse;
         Student student;
         Scanner scanner = new Scanner(System.in);

app/src/main/java/ru/project/datasource/RandomDataSource.java

@@ -3,34 +3,46 @@ package ru.project.datasource;
 import ru.project.student.Student;
 import ru.project.student.StudentBuilder;
 import ru.project.collection.MyList;
+import ru.project.collection.MyLinkedList;
 import java.util.Random;
 
 public class RandomDataSource implements  DataSource{
-    private final String CHARS = "АБВГДЕЖХИКЛМНОПРСТУФХЦЧЩЭЮЯ";
+    private final int size;
+    //private final String CHARS = "АБВГДЕЖХИКЛМНОПРСТУФХЦЧЩЭЮЯ";
+    private int upperBounRecordBookNumber;
+
+    public RandomDataSource(int size) {
+        this.size = size;
+    }
+
+    public void setUpperBounRecordBookNumber(int upperBounRecordBookNumber) {
+        this.upperBounRecordBookNumber = upperBounRecordBookNumber;
+    }
 
     private String getRandomGroupNumber(Random random){
-        StringBuilder buildRes = new StringBuilder(CHARS.charAt(random.nextInt(CHARS.length())));
-        buildRes.append('-');
-        buildRes.append(String.format("%03d", random.nextInt(999)));
-        return buildRes.toString();
+        char prefix = (char)(random.nextInt(26) + (int)'A')4
+        String result = prefix + String.format("%02d", random.nextInt(100));
+        return result;
     }
-    private String getRandomRecordBookNumber(Random random){
+    /*private String getRandomRecordBookNumber(Random random){
         StringBuilder buildRes = new StringBuilder(CHARS.charAt(random.nextInt(CHARS.length())));
         buildRes.append(String.format("%08d", random.nextInt(99999999)));
         return buildRes.toString();
-    }
+    }*/
 
     @Override
-    public MyList<Student> fill(int size) {
+    public MyList<Student> create() {
+        if (upperBounRecordBookNumber < 0)
+            throw new IllegalException("The upper bound is negative!!!");
         Random random = new Random();
-        MyList<Student> result = new MyList<>();
+        MyList<Student> result = new MyLinkedList<>();
         for (short i = 0; i<size; i++){
             result.add(new StudentBuilder()
                     .setGroupNumber(getRandomGroupNumber(random))
                     .setAverageGrade(Math.random() * 5.0)
-                    .setRecordBookNumber(getRandomRecordBookNumber(random))
+                    .setRecordBookNumber(random.nextInt(upperBounRecordBookNumber + 1))
                     .build());
         }
-        return null;
+        return result;
     }
 }

app/src/main/java/ru/project/datasource/StudentBuffer.java

@@ -0,0 +1,37 @@
+package ru.project.datasource;
+
+public class StudentBuffer {
+    private String groupNumber;
+    private double averageGrade;
+    private int recordBookNumber;
+
+    public StudentBuffer(String groupNumber, double averageGrade, Integer recordBookNumber) {
+        this.groupNumber = groupNumber;
+        this.averageGrade = averageGrade;
+        this.recordBookNumber = recordBookNumber;
+    }
+
+    public String getGroupNumber() {
+        return groupNumber;
+    }
+
+    public void setGroupNumber(String groupNumber) {
+        this.groupNumber = groupNumber;
+    }
+
+    public double getAverageGrade() {
+        return averageGrade;
+    }
+
+    public void setAverageGrade(double averageGrade) {
+        this.averageGrade = averageGrade;
+    }
+
+    public int getRecordBookNumber() {
+        return recordBookNumber;
+    }
+
+    public void setRecordBookNumber(int recordBookNumber) {
+        this.recordBookNumber = recordBookNumber;
+    }
+}