java - 无法使用另一个类正确访问数组

Question

我正在尝试获取在类 LightsOutPuzzle 类中初始化的 outputArray 值，求解。但是在打印数组的元素之后

1) 在LightsOutPuzzle中调用类解决之前 2)调用solve后，元素不相等，就像重新初始化了一样。

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.util.StringTokenizer;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;

public class LightsOutPuzzle extends JFrame implements ActionListener {

    public JFrame f;
    public JPanel p1;
    public JPanel p2;
    public JButton[] buttonArray;
    public JButton solve;
    public int nRows = 5;
    public int nColumns = 5;
    public int nTotalButtons = nRows * nColumns;
    public int[] outputArray = new int[25];

    public void create() {
        init();
        gui();
    }

    public void gui() {
        f = new JFrame("Lights Out Puzzle");
        f.setVisible(true);
        f.setSize(500,500);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        p2 = new JPanel();

        solve = new JButton("Solve");

        p2.add(solve);

        f.add(p1);
        f.add(p2, BorderLayout.SOUTH);

        solve.addActionListener(new Action());
    }

    public void init() {    
        p1 = new JPanel();
        p1.setLayout(new GridLayout(nRows, nColumns, 0, 0));

        int[] inputArray = new int[25];
        int i=0;

        buttonArray = new JButton[nTotalButtons];
        for (int nNum = 0; nNum < nTotalButtons; nNum++) 
        {
            buttonArray[nNum] = new JButton("");
            add(buttonArray[nNum]);
            //clickability
            buttonArray[nNum].addActionListener(this);
            buttonArray[nNum].setBackground(Color.yellow);
            buttonArray[nNum].setActionCommand("" + nNum);
        }

        //reading config file
        BufferedReader br = null;
        try {
            String line;
            br = new BufferedReader(new FileReader("input.txt"));

            while ((line = br.readLine()) != null) {
               StringTokenizer stringTokenizer = new StringTokenizer(line, " ");
               while (stringTokenizer.hasMoreElements()) {
                    inputArray[i] = Integer.parseInt(stringTokenizer.nextElement().toString());
                    i++;
               }
            }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (br != null)
                    br.close();

            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }

        //drawing text input
        for(i=0; i<nTotalButtons; i++){
            if(inputArray[i] == 1)
                buttonArray[i].setBackground(Color.white);
            p1.add(buttonArray[i]);
        }
    }

    public void save() {
        int i = 0;      
        for (i=0; i<25; i++) {
            if(buttonArray[i].getBackground() == Color.yellow)
                outputArray[i] = 1;
            else 
                outputArray[i] = 0;
        }
    }

    @Override
    public void actionPerformed(ActionEvent e) 
    {
        //conditions for the puzzle
    }

    public class Action implements ActionListener {
        public void actionPerformed (ActionEvent e) {
            int i;

            save();
            for(i=0; i<25; i++)
                System.out.println(outputArray[i]);
            new solve();
        }
    }

    public static void main(String[] args) {
        LightsOutPuzzle lop = new LightsOutPuzzle();
        lop.create();
    }
}

此时，outputArray 的所有元素都等于 1。但是，当我使用其他类解决时打印它们，outputArray 的所有元素都为现在等于 0。

import java.awt.*; 
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.util.*;

public class solve extends LightsOutPuzzle {
private JFrame f;
private JPanel p1;

int[] inputArray = new int[25];
int[] zeroArray = new int[25];
int[] UIState = new int[25];
int[] boardState = new int[25];
Queue<int[]> queue = new LinkedList<int[]>();

public solve() {
    gui();
    init();
}

public void gui() {
    f = new JFrame("Solution");
    f.setVisible(true);
    f.setSize(500,500);
    f.setLocationRelativeTo(null);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    p1 = new JPanel();
    p1.setLayout(new GridLayout(nRows, nColumns, 0, 0));

    buttonArray = new JButton[nTotalButtons];
    for (int nNum = 0; nNum < nTotalButtons; nNum++) {
        buttonArray[nNum] = new JButton("");
        add(buttonArray[nNum]);
        //buttonArray[nNum].setBackground(Color.white);
        buttonArray[nNum].setActionCommand("" + nNum);
        p1.add(buttonArray[nNum]);
    }

    f.add(p1);
}

public void init() {
    //drawing text input
    int i;
        for(i=0; i<25; i++)
            System.out.println(outputArray[i]);
    for(i=0; i<nTotalButtons; i++){
        if(outputArray[i] == 1)
            buttonArray[i].setBackground(Color.yellow);
    }
}

public static void main(String[] args) {
}

}

我还希望了解有关 Java 正确编程实践的提示。我已经很长时间没有用这种语言编写代码了，所以我只是尝试根据我的内存来创建一个程序..

Answer 1

尽管 solve 类扩展了 LightsOutPuzzle，但它是一个不同的对象，因此拥有自己的 outputArray 副本。在代码的第一部分中，您将打印 LightsOutPuzzle 中的 outputArray 实例，该实例已初始化为 1:

LightsOutPuzzle 中的 ActionListener

    public class Action implements ActionListener {
        public void actionPerformed (ActionEvent e) {
            int i;

            save();
            for(i=0; i<25; i++)
                    {
                      /////////////PRINTS OUT outputArray IN LightsOutPuzzle
                      System.out.println(outputArray[i]);
                    }

                    ////CREATES NEW solve OBJECT WITH ITS OWN outputArray COPY
                    new solve();
        }
    }

然后，当您调用 solve 构造函数时，您将打印尚未初始化且全为零的 solve 副本:

解决类中的初始化方法

public void init() {
    //drawing text input
    int i;
        for(i=0; i<25; i++)
                     {
                         //////PRINTS OUT outputArray IN solve CLASS
                         System.out.println(outputArray[i]);
                     }
                     for(i=0; i<nTotalButtons; i++){
                        if(outputArray[i] == 1)
                           buttonArray[i].setBackground(Color.yellow);
                      }
      }