数独ゲームを作成しており、ゲームを保存、名前を付けて保存、および開くオプションを提供しようとしています。これを行うために JFileChooser を使用しています。保存 (または「名前を付けて保存」) はできますが、保存したファイルを開こうとするとエラーが発生します。私はプログラミングが初めてで、誰かが問題を見つけて、保存するときに数独ボードの内容を読み込む方法を教えてくれることを願っています (また、開いたときに数独ボードを再作成する方法も教えてください)ファイル）。Reader/Writer の代わりに InputStream/OutputStream を使用してこれを処理する簡単な方法があると聞きました...
これを実装する内部クラスのコードを次に示します (このテキスト ボックスの文字制限を超えずにクラス全体を投稿する方法があるかどうかはわかりません)。
// this inner class provides a JMenuBar object at the top of
// the board
class MenuAtTop extends JMenuBar implements ActionListener{
// SudokuMain2 object we are dealing with
private SudokuMain2 main;
// the "File" menu
private JMenu fileMenu;
// the "New Game" option
private JMenuItem newGame;
// the "Open" option
private JMenuItem open;
// the "Save" option
private JMenuItem save;
// the "Save As" option
private JMenuItem saveAs;
// the "Reset" option
private JMenuItem reset;
// the "Quit" option
private JMenuItem quit;
// the ability to choose files
private JFileChooser choose;
// the saved file
// // compiler would not allow "static" keyword
private File fileSaved = null;
private Object opener;
// JDialog object to create a dialog box to prompt
// user for new game information
private JDialog createNewWin;
/**
* Constructs MenuAtTop object.
*
* @param m The SudokuMain2 object to be referred to.
*/
public MenuAtTop(final SudokuMain2 m) {
main = m;
opener = null;
choose = new JFileChooser();
// instantiate and bind to reference
fileMenu = new JMenu("File");
add(fileMenu);
// instantiate and bind to reference
newGame = new JMenuItem("New Game");
newGame.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_N,
ActionEvent.CTRL_MASK));
fileMenu.add(newGame);
newGame.addActionListener(this);
open = new JMenuItem("Open");
open.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_O,
ActionEvent.CTRL_MASK));
fileMenu.add(open);
// add action listener to "Open" option
open.addActionListener(this);
save = new JMenuItem("Save");
save.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_S,
ActionEvent.CTRL_MASK));
fileMenu.add(save);
// //save.setEnabled(false);
// add action listener to "Save" option
save.addActionListener(this);
saveAs = new JMenuItem("Save As");
saveAs.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_A,
ActionEvent.CTRL_MASK));
fileMenu.add(saveAs);
// add action listener to "Save As" option
saveAs.addActionListener(this);
reset = new JMenuItem("Reset");
reset.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_R,
ActionEvent.CTRL_MASK));
fileMenu.add(reset);
// add action listener to "Reset" option
reset.addActionListener(this);
quit = new JMenuItem("Quit");
quit.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Q,
ActionEvent.CTRL_MASK));
fileMenu.add(quit);
// add action listener to "Quit" option
quit.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
if(e.getSource().equals(quit)) {
closePrompt();
//main.win.dispose();
}
else if(e.getSource().equals(reset)) {
int n = JOptionPane.showConfirmDialog(main.win,
"Any player values will" +
" be lost. Proceed?",
"Warning!", 2);
if(n == JOptionPane.OK_OPTION) {
main.board.reset();
main.view.repaint();
}
}
else if(e.getSource().equals(saveAs)) {
saveAs();
}
else if(e.getSource().equals(save)) {
if(fileSaved == null) {
saveAs();
}
else {
try {
board.writeToStream(new FileOutputStream(fileSaved));
// main.board.setDirty(false);
} catch (Exception ex) {
JOptionPane.showMessageDialog(main.win, "Error saving file.");
}
}
}
else if(e.getSource().equals(open)) {
int returnVal = choose.showOpenDialog(main.win);
if(returnVal == JFileChooser.APPROVE_OPTION) {
boolean error = false;
File openFile = choose.getSelectedFile();
try {
FileInputStream fin = new FileInputStream(openFile);
ObjectInputStream ois = new ObjectInputStream(fin);
opener = ois.readObject();
} catch (Exception ex) {
JOptionPane.showMessageDialog(main.win, "Error opening file.");
error = true;
}
if(opener != null && opener instanceof SudokuBase){
main.west.remove(main.symbols);
main.east.remove(main.view);
//add in state information for new board
main.south.remove(main.rowColRegStates);
main.view = new SudokuView((SudokuBase) opener);
main.symbols = new SetSymbols(main.view);
//add in state information for new board
main.rowColRegStates = new ShowStates(main.view);
main.west.add(main.symbols);
main.east.add(main.view);
//add in state information for new board
main.south.add(main.rowColRegStates);
main.win.requestFocus();
fileSaved = openFile;
// main.board.setDirty(false);
} else {
if(error) {
JOptionPane.showMessageDialog(main.win, " Incorrect file type!");
}
}
}
// else: user cancelled
}
else if(e.getSource().equals(newGame)) {
setEnabled(false);
// create dialog box prompting for the new board information
createNewWin = new Dialog1(main, "Create New Board", true);
// make it visible
createNewWin.setVisible(true);
fileSaved = null;
}
}
// This method prompts the user to choose a file to save to,
// and then saves the file.
private int saveAs() {
boolean saveError;
int rtn = choose.showSaveDialog(main.win);
if(rtn == JFileChooser.APPROVE_OPTION) {
saveError = false;
File fileSaveAs = choose.getSelectedFile();
try {
board.writeToStream(new FileOutputStream(fileSaveAs));
} catch (Exception e) {
JOptionPane.showMessageDialog(main.win, "Error saving file.");
saveError = true;
}
if(!saveError) {
fileSaved = fileSaveAs;
// main.board.setDirty(false);
}
}
return rtn;
}
/**
* Asks the user if they want to save before closing if changes were made.
*/
private void closePrompt() {
if(true) { //board.isDirty()) {
int n = JOptionPane.showConfirmDialog(main.win, "Save game?");
if(n == JOptionPane.YES_OPTION) {
int saved = saveAs();
if(saved != JFileChooser.CANCEL_OPTION){
main.win.dispose();
}
}
else if(n == JOptionPane.NO_OPTION) {
main.win.dispose();
}
}
else
main.win.dispose();
}
}