diff --git a/src/main/java/Field.java b/src/main/java/Field.java
new file mode 100644
index 0000000..f08566c
--- /dev/null
+++ b/src/main/java/Field.java
@@ -0,0 +1,178 @@
+import java.util.Arrays;
+import java.util.Objects;
+
+public final class Field {
+    public final int size; // длина стороны поля
+    private final char[][] view;
+    private int theLongestCross;
+    private int theLongestNought;
+
+    public Field(int size) {   // конструктор
+        this.size = size;
+        view = new char[size][size];
+        for (char[] row : view) {
+            java.util.Arrays.fill(row, ' ');
+        }
+    }
+
+    public Field() {   // конструктор
+        this.size = 3;
+        view = new char[size][size];
+        for (char[] row : view) java.util.Arrays.fill(row, ' ');
+    }
+
+    public void show() {
+        System.out.println("Состояние поля:");
+        for (char[] i : view) {
+            for (char j : i) System.out.print(j + " ");
+            System.out.println();
+        }
+
+    }
+
+    public void addNought(int row, int column) throws Exception {
+        if (row < 1 || row > size || column < 1 || column > size) {
+            throw new Exception("Ошибка: В данном поле не существует такого ряда и/или столбца.");
+        } else if (view[row - 1][column - 1] != ' ') {
+            throw new Exception("Ошибка: Ячейка уже занята.");
+        }
+        view[row - 1][column - 1] = 'O';
+    }
+
+    public void addCross(int row, int column) throws Exception {
+        if (row < 1 || row > size || column < 1 || column > size) {
+            throw new Exception("Ошибка: В данном поле не существует такого ряда и/или столбца.");
+        } else if (view[row - 1][column - 1] != ' ') {
+            throw new Exception("Ошибка: Ячейка уже занята.");
+        }
+        view[row - 1][column - 1] = 'X';
+    }
+
+    public void clearCell(int row, int column) throws Exception {
+        if (row < 1 || row > size || column < 1 || column > size) {
+            throw new Exception("Ошибка: В данном поле не существует такого ряда и/или столбца.");
+        }
+        view[row - 1][column - 1] = ' ';
+    }
+
+    public int theLongestCross() {
+        int[] count = {0, 0, 0, 0};
+        // проверка рядов и строк
+        for (int i = 0; i < size; i++) {
+            for (int j = 0; j < size; j++) {
+                if (view[i][j] == 'X') count[0]++;
+                else {
+                    if (count[0] > theLongestCross) theLongestCross = count[0];
+                    count[0] = 0;
+                }
+                if (view[j][i] == 'X') count[1]++;
+                else {
+                    if (count[1] > theLongestCross) theLongestCross = count[1];
+                    count[1] = 0;
+                }
+            }
+            for (int k = 0; k <= 1; k++) {
+                if (count[k] > theLongestCross) theLongestCross = count[k];
+                count[k] = 0;
+            }
+        }
+        // проверка диагоналей
+        for (int i = 0; i < size; i++){
+            for (int j = 0; j <= i; j++) {
+                if (view[j][i - j] == 'X') count[0]++;
+                else {
+                    if (count[0] > theLongestCross) theLongestCross = count[0];
+                    count[0] = 0;
+                }
+                if (view[size - 1 - j][size - 1 - i + j] == 'X') count[1]++;
+                else {
+                    if (count[1] > theLongestCross) theLongestCross = count[1];
+                    count[1] = 0;
+                }
+                if (view[j][size - 1 - i + j] == 'X') count[2]++;
+                else {
+                    if (count[2] > theLongestCross) theLongestCross = count[2];
+                    count[2] = 0;
+                }
+                if (view[size - 1 - j][i - j] == 'X') count[3]++;
+                else {
+                    if (count[3] > theLongestCross) theLongestCross = count[3];
+                    count[3] = 0;
+                }
+            }
+            for (int k = 0; k <= 3; k++) {
+                if (count[k] > theLongestCross) theLongestCross = count[k];
+                count[k] = 0;
+            }
+        }
+        return theLongestCross;
+    }
+    public int theLongestNought() {
+        int[] count = {0, 0, 0, 0};
+        // проверка рядов и строк
+        for (int row = 0; row < size; row++) {
+            for (int column = 0; column < size; column++) {
+                if (view[row][column] == 'O') count[0]++;
+                else {
+                    if (count[0] > theLongestNought) theLongestNought = count[0];
+                    count[0] = 0;
+                }
+                if (view[column][row] == 'O') count[1]++;
+                else {
+                    if (count[1] > theLongestNought) theLongestNought = count[1];
+                    count[1] = 0;
+                }
+            }
+            for (int k = 0; k <= 1; k++) {
+                if (count[k] > theLongestNought) theLongestNought = count[k];
+                count[k] = 0;
+            }
+        }
+        // проверка диагоналей
+        for (int i = 0; i < size; i++){
+            for (int j = 0; j <= i; j++) {
+                if (view[j][i - j] == 'O') count[0]++;
+                else {
+                    if (count[0] > theLongestNought) theLongestNought = count[0];
+                    count[0] = 0;
+                }
+                if (view[size - 1 - j][size - 1 - i + j] == 'O') count[1]++;
+                else {
+                    if (count[1] > theLongestNought) theLongestNought = count[1];
+                    count[1] = 0;
+                }
+                if (view[j][size - 1 - i + j] == 'O') count[2]++;
+                else {
+                    if (count[2] > theLongestNought) theLongestNought = count[2];
+                    count[2] = 0;
+                }
+                if (view[size - 1 - j][i - j] == 'O') count[3]++;
+                else {
+                    if (count[3] > theLongestNought) theLongestNought = count[3];
+                    count[3] = 0;
+                }
+            }
+            for (int k = 0; k <= 3; k++) {
+                if (count[k] > theLongestNought) theLongestNought = count[k];
+                count[k] = 0;
+            }
+        }
+        return theLongestNought;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Field field = (Field) o;
+        return size == field.size
+                && Arrays.deepEquals(view, field.view);
+    }
+
+    @Override
+    public int hashCode() {
+        int result = Objects.hash(size, theLongestCross, theLongestNought);
+        result = 31 * result + Arrays.deepHashCode(view);
+        return result;
+    }
+}
diff --git a/src/main/java/Main.java b/src/main/java/Main.java
new file mode 100644
index 0000000..cf11cfb
--- /dev/null
+++ b/src/main/java/Main.java
@@ -0,0 +1,14 @@
+/**
+Вариант 15 -- поле для крестиков-ноликов [Java]
+Хранит квадратное поле для игры в крестики-нолики заданного в конструкторе
+размера.
+Методы: добавление крестика / нолика в заданную клетку, очистка заданной клетки,
+поиск самой длинной последовательности крестиков (непрерывной линии по
+горизонтали / вертикали / диагонали), то же для ноликов.
+*/
+
+public final class Main {
+    public static void main(String[] args) {
+        Field a = new Field();
+    }
+}
diff --git a/src/test/java/FieldTest.java b/src/test/java/FieldTest.java
new file mode 100644
index 0000000..3fecb9a
--- /dev/null
+++ b/src/test/java/FieldTest.java
@@ -0,0 +1,75 @@
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+public class FieldTest {
+
+    @Test
+    public void testAddNought() throws Exception {
+        Field FieldA = new Field();
+        Field FieldB = new Field(3);
+        assertThrows(Exception.class, () -> FieldA.addNought(8, 5),
+                "Ошибка: В данном поле не существует такого ряда и/или столбца.");
+        FieldA.addNought(2,3);
+        assertThrows(Exception.class, () -> FieldA.addNought(2, 3),
+                "Ошибка: Ячейка уже занята.");
+        FieldB.addNought(2, 3);
+        assertEquals(FieldA, FieldB);
+        FieldA.addNought(1,1);
+        assertNotEquals(FieldA, FieldB);
+    }
+
+    @Test
+    public void testAddCross() throws Exception {
+        Field FieldA = new Field();
+        assertThrows(Exception.class, () -> FieldA.addCross(8, 5),
+                "Ошибка: В данном поле не существует такого ряда и/или столбца.");
+        Field FieldB = new Field(3);
+        FieldA.addCross(1,2);
+        assertThrows(Exception.class, () -> FieldA.addCross(1, 2),
+                "Ошибка: Ячейка уже занята.");
+        FieldB.addCross(1, 2);
+        assertEquals(FieldA, FieldB);
+        FieldA.addCross(1,1);
+        assertNotEquals(FieldA, FieldB);
+
+    }
+
+    @Test
+    public void testClearCell() throws Exception {
+        Field FieldA = new Field();
+        assertThrows(Exception.class, () -> FieldA.clearCell(8, 5),
+                "Ошибка: В данном поле не существует такого ряда и/или столбца.");
+        Field FieldB = new Field(3);
+        FieldA.addCross(1,2);
+        FieldA.addNought(1, 3);
+        FieldB.addCross(1, 2);
+        FieldB.addNought(1, 3);
+        FieldA.clearCell(1,2);
+        assertNotEquals(FieldA, FieldB);
+        FieldB.clearCell(1,2);
+        assertEquals(FieldA, FieldB);
+    }
+    @Test
+    public void testTheLongestNought() throws Exception {
+        Field FieldA = new Field(4);
+        FieldA.addCross(1,1);
+        FieldA.addNought(1, 2);
+        FieldA.addNought(1, 3);
+        FieldA.addNought(1, 4);
+        FieldA.addNought(2, 2);
+        assertEquals(3, FieldA.theLongestNought());
+    }
+    @Test
+    public void testTheLongestCross() throws Exception {
+        Field FieldA = new Field(4);
+        FieldA.addNought(1,1);
+        FieldA.addNought(3,2);
+        FieldA.addCross(2, 1);
+        FieldA.addCross(2, 2);
+        FieldA.addCross(1, 3);
+        FieldA.addCross(3, 3);
+        FieldA.addCross(4, 4);
+        assertEquals(3, FieldA.theLongestCross());
+    }
+}