A Java exercise that aims to reproduce the classic snake game

Garden.java

import java.util.Random;

public class Garden {
    private Unit[][] grid;  //The grid represents the game field
    private int[] gridSize = new int[2];
    private boolean isGameOver = false;
    private String lastMove = "0";
    //Create a new Snake instance defining initial length and coordinates
    private Snake snakePlayer = new Snake(3, 7, 2);

    //Constructor
    public Garden (int r, int c) {
        this.grid = new Unit[r][c];
        this.gridSize[0] = r;
        this.gridSize[1] = c;
        for (int y = 0; y < this.grid.length; y++) {
            for (int x = 0; x < c; x++) {
                this.grid[y][x] = new Unit(x, y);
            }
        }
    }

    public void spawnFood() {
        Random random = new Random();
        //Defining food coordinates range
        int foodX = Math.max(1, random.nextInt(this.gridSize[1])-1);
        int foodY = Math.max(1, random.nextInt(this.gridSize[0])-1);
        //Remember this.grid[y][x] ( rows(y) come before columns(c) )
        if (!this.snakePlayer.getSnakeBody().contains(this.grid[foodY][foodX])) {
            this.grid[foodY][foodX].setFood(true);
        }
        else {
            spawnFood();
        }
    }

    public boolean limitBreak(int xCoord, int yCoord) {
        //Remember that in this.grid[y][x] the 'y'[1](rows) comes before than 'x'[0](columns)
        if (xCoord < 0 || xCoord >= this.gridSize[1] ||
                yCoord < 0 || yCoord >= this.gridSize[0]) {
            System.out.println("- GAME OVER -");
            this.isGameOver = true;
            return true;
        }
        return false;
    }

    public void snakeMovement(char m) {
        switch (m) {
            //The first 'if' statement verify movement conditions and call the gameOver function
            case 'w' :
                if (this.limitBreak(this.snakePlayer.getSnakeHead().getCoords()[0],
                        this.snakePlayer.getSnakeHead().getCoords()[1] - 1) ||
                                    this.lastMove.charAt(0) == 's') {
                    return;
                }
                this.snakePlayer.move(this.snakePlayer.getSnakeHead().getCoords()[0],
                        this.snakePlayer.getSnakeHead().getCoords()[1] - 1);
                this.lastMove = String.valueOf(m);
                break;

            case 'a' :
                if (this.limitBreak(this.snakePlayer.getSnakeHead().getCoords()[0] - 1,
                        this.snakePlayer.getSnakeHead().getCoords()[1]) ||
                                    this.lastMove.charAt(0) == 'd') {
                    return;
                }
                this.snakePlayer.move(this.snakePlayer.getSnakeHead().getCoords()[0] - 1,
                        this.snakePlayer.getSnakeHead().getCoords()[1]);
                this.lastMove = String.valueOf(m);
                break;

            case 's' :
                if (this.limitBreak(this.snakePlayer.getSnakeHead().getCoords()[0],
                        this.snakePlayer.getSnakeHead().getCoords()[1] + 1) ||
                                    this.lastMove.charAt(0) == 'w') {
                    return;
                }
                this.snakePlayer.move(this.snakePlayer.getSnakeHead().getCoords()[0],
                        this.snakePlayer.getSnakeHead().getCoords()[1] + 1);
                this.lastMove = String.valueOf(m);
                break;

            case 'd' :
                if (this.limitBreak(this.snakePlayer.getSnakeHead().getCoords()[0] + 1,
                        this.snakePlayer.getSnakeHead().getCoords()[1]) ||
                                    this.lastMove.charAt(0) == 'a') {
                    return;
                }
                this.snakePlayer.move(this.snakePlayer.getSnakeHead().getCoords()[0] + 1,
                        this.snakePlayer.getSnakeHead().getCoords()[1]);
                this.lastMove = String.valueOf(m);
                break;
        }
        //Eating if the cell has food
        //Remember this.grid[y][x] ('y' comes before than 'x')
        if (this.grid[this.snakePlayer.getSnakeHead().getCoords()[1]]
                [this.snakePlayer.getSnakeHead().getCoords()[0]].getFood()) {
            //Remove food
            this.grid[this.snakePlayer.getSnakeHead().getCoords()[1]]
                    [this.snakePlayer.getSnakeHead().getCoords()[0]].setFood(false);
            //Add element body in the right direction (it depends on the last movement)
            switch (m) {
                case 'w' :
                    this.snakePlayer.addElement(this.snakePlayer.getSnakeHead().getCoords()[0],
                            this.snakePlayer.getSnakeHead().getCoords()[1] - 1);
                    break;

                case 'a' :
                    this.snakePlayer.addElement(this.snakePlayer.getSnakeHead().getCoords()[0]-1,
                            this.snakePlayer.getSnakeHead().getCoords()[1]);
                    break;

                case 's' :
                    this.snakePlayer.addElement(this.snakePlayer.getSnakeHead().getCoords()[0],
                            this.snakePlayer.getSnakeHead().getCoords()[1] + 1);
                    break;

                case 'd' :
                    this.snakePlayer.addElement(this.snakePlayer.getSnakeHead().getCoords()[0]+1,
                            this.snakePlayer.getSnakeHead().getCoords()[1]);
                    break;
            }
            //Respawn food
            this.spawnFood();
        }
    }

    public boolean gameOver() {
        if (this.snakePlayer.checkHeadWithBody()) {
            this.isGameOver = true;
            System.out.println("((( Self-Injury )))");
        }
        return this.isGameOver;
    }

    @Override
    public String toString() {
        // ❑ ▣ ● ⊙
        String out = "";
        if (this.isGameOver) {
            return "| You Lose |";
        }
        for (int y = 0; y < this.grid.length; y++) {
            for (int x = 0; x < this.grid[y].length; x++) {
                if (snakePlayer.getSnakeBody().contains(this.grid[y][x])) {
                    out += (snakePlayer.getSnakeHead().equals(this.grid[y][x])) ? " ● " : " ▣ ";
                }
                else {
                    out += (this.grid[y][x].getFood()) ? " ⊙ " : " ❑ ";
                }
            }
            out += "\n";
        }
        return out;
    }

}

Main.java

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner userInput = new Scanner(System.in);

        //Creating the game field
        Garden gard = new Garden(8, 15);

        //First food spawn
        gard.spawnFood();

        System.out.println(gard);

        //Playing
        while(!gard.gameOver()) {
            System.out.println("Digita mossa: ");
            char playerMove = userInput.next().charAt(0);
            gard.snakeMovement(playerMove);
            System.out.println(gard);
        }
    }

}

Snake.java

import java.util.ArrayList;

public class Snake {
    private ArrayList<Unit> snakeBody = new ArrayList<Unit>();

    //Constructor
    public Snake(int sl, int sx, int sy) {
        //Initial size and coordinates
        for (int x = 0; x < sl; x++) {
            this.snakeBody.add(new Unit(sx-x, sy));  //Add new elements behind the first one (sx-x)
        }
        //Set snake head
        this.snakeBody.get(0).setHead(true);
    }

    public ArrayList<Unit> getSnakeBody() {
        return this.snakeBody;
    }

    public Unit getSnakeHead() {
        //Return the head in order to draw it correctly
        return this.snakeBody.get(0);
    }

    public boolean checkHeadWithBody() {
        for (int i = 1; i < this.snakeBody.size(); i++) {
            //Comparing head and body elements coordinates
            if (this.getSnakeHead().getCoords()[0] == this.snakeBody.get(i).getCoords()[0] &&
                    this.getSnakeHead().getCoords()[1] == this.snakeBody.get(i).getCoords()[1]) {
                return true;
            }
        }
        return false;
    }

    public void move(int x, int y) {
        //The movement is based on the head coordinates
        int[] previousPos = {this.getSnakeHead().getCoords()[0], this.getSnakeHead().getCoords()[1]};
        int[] posMemo = new int[2];
        this.getSnakeHead().setCoords(x, y);    //Set new head position
        //Shift body elements
        for (int i = 1; i < snakeBody.size(); i++) {
            posMemo[0] = this.snakeBody.get(i).getCoords()[0];
            posMemo[1] = this.snakeBody.get(i).getCoords()[1];
            this.snakeBody.get(i).setCoords(previousPos[0], previousPos[1]);
            previousPos[0] = posMemo[0];
            previousPos[1] = posMemo[1];
        }
    }

    //Growth function
    public void addElement(int x, int y) {
        this.snakeBody.add(0, new Unit(x, y));
    }

}

Unit.java

public class Unit {
    private int[] coords = new int[2];
    private boolean head = false;
    private boolean food = false;

    //Constructor
    public Unit(int x, int y) {
        this.coords[0] = x;
        this.coords[1] = y;
    }

    public void setHead(boolean value) {
        this.head = value;
    }

    public void setFood(boolean value) {
        this.food = value;
    }
    public boolean getFood() {
        return this.food;
    }

    public void setCoords(int x, int y) {
        this.coords[0] = x;
        this.coords[1] = y;
    }
    public int[] getCoords() {
        return this.coords;
    }

    @Override
    public boolean equals(Object o) {
        Unit objectIn = (Unit) o;
        if (objectIn.getCoords()[0] == this.coords[0]
                && objectIn.getCoords()[1] == this.coords[1]) {
            return true;
        }
        else {
            return false;
        }
    }

    @Override
    public String toString() {
        return "X coord : " + this.coords[0] + "\n" + "Y coord: " + this.coords[1];
    }

}