序列化一个圆[] []？

Question

I have a pixel editor app and I need to save to a file the pixelArray created. Serializing the pixelArray of Circle objects seems like the practical solution so I create the following class:

public class PixelArray implements Serializable{
    static Circle[][] pixelArray;
    public static  Circle[][] pixArray (int row, int col){
        pixelArray = new Circle[row][col];
        return pixelArray;
    }
}

The SaveFile class includes a JFileChooser and saveFile method for to Serialize the pixelArray as follows:

public class SaveFile {

public static void write(){
    String fileName;
    fileName = "PixelArray1.pix";
    JFileChooser fileDialog = new JFileChooser( "C:\\Program Files (x86)\\Visual Art\\Playlist\\");
    File selectedFile = new File(fileName);
    fileDialog.setSelectedFile(selectedFile);
    fileDialog.setDialogTitle("Save Pixel File");
    fileDialog.setSelectedFile(null);
    fileDialog.setSize(400, 400);
    fileDialog.setVisible(true);
    int option = fileDialog.showSaveDialog(null);
    if(option != JFileChooser.APPROVE_OPTION)
        return;                                         //user canceled of clicked the dialog's close box
    selectedFile = fileDialog.getSelectedFile();
    if(selectedFile.exists()){                          //ask the user to replace this file
        int response = JOptionPane.showConfirmDialog(null,"The file \""+ selectedFile.getName() +
        "\" already exists.\nDo you want to replace it?",
        "Confirm Save",
        JOptionPane.YES_NO_OPTION,
        JOptionPane.WARNING_MESSAGE );
        if(response != JOptionPane.YES_OPTION) return;  //user does not want ot replace the fle
    }
    saveFile(pixelArray, "PixelArray1.pix");                 //Serialize
}

public static void saveFile(Circle[][] pixelArray, String fileName){      //Serialize
    try {
        FileOutputStream fos = new FileOutputStream(fileName);
        ObjectOutputStream out = new ObjectOutputStream(fos);
        out.writeObject(pixelArray);
        out.flush();
        out.close();
    }
    catch (IOException e){
        System.out.println(e);
    }
}

Try as I may as a newbie, I can't get past the exception:

java.io.NotSerializableException: javafx.scene.shape.Circle

Serializing a Circle[][] shouldn't be that hard; what am I missing, please?

Answer 1

Probably you should read documentation of the specific exception, it states:

Thrown when an instance is required to have a Serializable interface. The serialization runtime or the class of the instance can throw this exception. The argument should be the name of the class.

This because Java serialization requires to tag classes which are supposed to be serializable with the Serializable interface:

class Circle implements Serializable
{
  ...
}

If the class you are working on is not modifiable, then you must provide your own bridge class, eg:

class SerializableCircle implements Serializable
{
  // create a serializable circle from a Circle
  SerializableCircle(Circle circle) {
    ..
  }

  // create a Circle back from an unserialized circle
  Circle unserialize()
  {
    ..
  }
};

and then serialize and unserialize this.

Answer 2

Since javafx.scene.shape.Circle is not serializable, you need to serialize something that is actually serializable.

To accomplish this, you could write a wrapper class who implements Serializable that has all the data needed to recreate a circle object when it is deserialized.

Here's something that should help with making a serializable class: http://www.javapractices.com/topic/TopicAction.do?Id=45

Answer 3

Now, I believe from the Answers given, it would be more practical to drop Serialization and figure out how to convert my Circle[][] to a Color[]. Then I would need to read/write Color[] to a file to Save/Open and send via Wi-Fi to microcontroller.