JPanel이 두 번 생성

전함 게임용 GUI를 만들려고합니다. 한 클래스는 GUI 자체를 생성하기위한 것이고 두 번째 클래스는 게임에서 보드를 관리하기위한 것입니다. 내 문제는 마우스 클릭이 발생하면 JPanel이 두 번 생성한다는 것입니다 (마우스 클릭은 게임에서 발사되는 곳으로 가정하고 히트 / 실패로 표시합니다). 왜 두 번 생성되는지 잘 모르겠습니다. 패널 통과 때문인가요? 아래 코드와 코드가 생성하는 사진.

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.BorderFactory;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;


public class BattleshipApplet extends JApplet implements MouseListener {
    private final JButton playButton = new JButton("Play");
    private final JLabel msgBar = new JLabel("Click Play to start game");
    private BoardPanel panel;



    public BattleshipApplet(){
        playButton.addActionListener(this::playButtonClicked);  
        addMouseListener(this);
    }

    public void init(){
        configureGui();
    }

    private void configureGui(){
        setLayout(new BorderLayout());
        JPanel buttons = new JPanel(new FlowLayout(FlowLayout.LEFT));
        buttons.setBorder(BorderFactory.createEmptyBorder(0,5,0,0));
        buttons.add(playButton);
        add(buttons, BorderLayout.NORTH);
        msgBar.setBorder(BorderFactory.createEmptyBorder(10,10,5,5));
        add(createBoardPanel(), BorderLayout.CENTER);
        add(msgBar, BorderLayout.SOUTH);
    }

    private BoardPanel createBoardPanel(){
        panel = new BoardPanel();
        return panel;
    }

    private void displayMessage(String msg){
        msgBar.setText(msg);
    }

    private void playButtonClicked(ActionEvent event){
        displayMessage("Play button clicked!");
    }

    public void mouseClicked(MouseEvent e) {
        panel.mouseClickedAt(e.getX(), e.getY());
        e.consume();
    }


    public void mouseEntered(MouseEvent e) {
    }


    public void mouseExited(MouseEvent e) {
    }  
    public void mousePressed(MouseEvent e) {
    }
    public void mouseReleased(MouseEvent e) {
    }   
}

JPanel을 사용하는 보드 클래스

[![import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;


public class BoardPanel extends JPanel  {
    int mx, my;
    boolean rect1Clicked;
    //gamePlay a;
    public void init(){

        rect1Clicked = false;

    }

    /***Your applet shall show the status of the board before and after
     each shot, including the number of shots made and the status of
     each place (no shot or hit/miss shot). ***/
    public void paint(Graphics g){
        boolean miss = false;


        for (int i=0; i<11; i++){ 
            g.setColor(Color.blue);
            g.drawLine(20,20+i*28, 300, 20+i*28);   
        }
        for (int i=0; i<11; i++)   
            g.drawLine(20+i*28,20,20+i*28,300);

        //if inside board 
        if(rect1Clicked == true){
            g.setColor(Color.green);
            //aligns to square to check in computer board for hit/miss
            int bx =(my-20)/28;
            int by =(mx-20)/28;



            //check hit on board
            //if shot was a miss
            if(miss == true ){
                //update to white
                g.setColor(Color.white);
            }
            //if shot was a hit
            if(miss == false){
                //update to red
                g.setColor(Color.red);
            }
            //compare to line for fill
            int fillx = mx/2;
            int filly = my/2 ;
            if(mx<=47){
                fillx = 20;
            }
            if(mx>47 && mx<=75){
                fillx = 48;
            }
            if(mx>75 && mx<=103){
                fillx = 76;
            }
            if(mx>103 && mx <=131){
                fillx = 104;
            }
            if(mx>131 && mx<=159){
                fillx = 132;
            }
            if(mx>159 && mx<=187){
                fillx = 160;
            }
            if(mx>187 && mx <=215){
                fillx = 188;
            }
            if(mx>215 && mx <=243){
                fillx = 216;
            }
            if(mx>243 && mx <=271){
                fillx = 244;
            }
            if(mx>271 && mx<=299){
                fillx = 272;
            }
            if(mx>299){
                fillx = 300;
            }
            //y comparisons
            if(my<=47){
                filly = 20;
            }
            if(my>47 && my<=75){
                filly = 48;
            }
            if(my>75 && my<=103){
                filly = 76;
            }
            if(my>103 && my <=131){
                filly = 104;
            }
            if(my>131 && my<=159){
                filly = 132;
            }
            if(my>159 && my<=187){
                filly = 160;
            }
            if(my>187 && my <=215){
                filly = 188;
            }
            if(my>215 && my <=243){
                filly = 216;
            }
            if(my>243 && my <=271){
                filly = 244;
            }
            if(my>271 && my<=299){
                filly = 272;
            }
            if(my>299){
                filly = 300;
            }


            g.drawString("("+mx+","+my+")",mx,my);
            //25 describes size of square 
            g.fillOval(fillx, filly, 25, 25);

        }


    }

    public void game(BoardPanel p){
        //while game plays
    }


    public void mouseClickedAt(int x, int y){

        mx = x;
        my = y;

        //user clicked inside of board space
        if(mx>20 && mx<300 && my>20 && my<300){       

            //send to board in MainBattleship
            rect1Clicked = true;

        }
        //updates board
        repaint();
    }


}][1]][1]

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