Java 编译器无法解析被覆盖的 JButton 的符号

Question

我正在编写一个编辑器，它创建一个按钮矩阵。单击时按钮的显示符号会发生变化。所以我创建了一个新的 class 扩展 JButton 并改变了一些东西。编译时，编译器告诉我，它无法解析符号 AlienGameButton。但为什么？我该如何解决这个问题？

package MapGenerator;
import javax.swing.*;
import javax.swing.JOptionPane;
import java.awt.*;

public class MapGenerator {
public static void main(String[] args) {


    //Initialisierung der Mapgröße über einen Input-Dialog

    int hight, width;
    hight = Integer.parseInt(JOptionPane.showInputDialog(null, "Höhe des Spielfeldes: "));
    width = Integer.parseInt(JOptionPane.showInputDialog(null, "Breite des Spielfeldes: "));
    System.out.println(width);
    System.out.println(hight);


    //Erstellen eines Fensters abhängig von der Anzahl der gewünschten Felder

    JFrame GeneratorFenster = new JFrame("Map Generator");
    GeneratorFenster.setSize(hight * 50 + 50, width * 50);
    GeneratorFenster.setVisible(true);

    AlienGameButton buttons[][] = new AlienGameButton[hight][width];

    GeneratorFenster.setLayout(new GridLayout(hight, width));
    for (int i = 0; i < hight; i++) {
        for (int j = 0; j < width; j++) {
            buttons[i][j] = new AlienGameButton();
            GeneratorFenster.add(buttons[i][j]);
        }

        GeneratorFenster.setVisible(true);

    }
}
}

以及我创建的按钮的 class：

package MapGenerator;

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class AlienGameButton extends JButton implements ActionListener {

private int count = 0;

public AlienGameButton() {
    this.addActionListener(this);
}


public void actionPerformed(ActionEvent e) {
    count += 1;
    count %= 3;
    switch (count) {
        case 0:
            setText(" ");
            break;

        case 1:
            setText("A");
            break;

        case 2:
            setText("#");
            break;

        case 3:
            setText("P");
            break;

        case 4:
            setText("O");
            break;

    }
}

}

这是编译器错误：

MapGenerator.java:26: error: cannot find symbol
AlienGameButton buttons[][] = new AlienGameButton[hight][width];
^
symbol:   class AlienGameButton
location: class MapGenerator
MapGenerator.java:26: error: cannot find symbol
AlienGameButton buttons[][] = new AlienGameButton[hight][width];
                                  ^
symbol:   class AlienGameButton
location: class MapGenerator
MapGenerator.java:31: error: cannot find symbol
buttons[i][j] = new AlienGameButton();
                            ^
symbol:   class AlienGameButton
location: class MapGenerator
3 errors

Answer 1

如评论中所述，如果您觉得尝试使用 javac FileName.java 进行编译，它是行不通的。请使用以下两个命令使其工作：

javac MapGenerator/AlienGameButton.java
javac MapGenerator/MapGenerator.java

而不是

javac AlienGameButton.java
javac MapGenerator.java

此外，正如您所说，当您将它移动到 src 目录时它开始工作，那是因为包被更改为默认包。

PS:

一些建议和编码标准：

Package name and class name should not be exactly same

Package name should always start from lowercase letter and class name should always start from uppercase letter

Java 编译器无法解析被覆盖的 JButton 的符号

Java Compiler cannt resolve the Symbol of overwritten JButton

java

inheritance

swing

compiler-errors

jbutton