Java - 保存 ArrayList<ObjectType> : application crash

Question

我需要一种方法来保存对象的 ArrayList。我在网站上浏览过类似的问题并且我(似乎 ;-) 已经实现了我发现的东西，但是我遇到了两个问题:

1. 如果我将类定义为 Serializable 并放置构造函数，它会在启动时崩溃
2. 否则不保存数组

你能帮忙吗？我正在为一个志愿者的项目开发代码，但我被困住了......

非常感谢您。

我的应用程序具有以下定义的类:Globals(文件 Globals.java)

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public class Globals extends Application implements Serializable {  

    private int position=-1;
    private ArrayList<RaccoltaPunti> raccoltePuntiList = new ArrayList<RaccoltaPunti>();
    public static final long serialVersionUID = 1L;
    /** constructor - seem required by Serializable, but creating it crashes app */
    public Globals(int position, ArrayList<RaccoltaPunti> raccoltePuntiList) {
        this.position = position;
        this.raccoltePuntiList = raccoltePuntiList;
    }
     // {getters and setters…}

    public void saveData(){

        String filename = getResources().getString(R.string.GLB_filename);
        String fileWithPath = this.getFilesDir().getPath().toString()+"/"+filename;
        Toast.makeText(this, "Salvataggio testo..."+ fileWithPath, Toast.LENGTH_LONG).show();
        try {
            FileOutputStream fos = new FileOutputStream(fileWithPath);
            ObjectOutputStream oos = new ObjectOutputStream(fos);
            oos.writeObject(this.raccoltePuntiList);    
            oos.close();
            Toast.makeText(Globals.this, "DatiSalvati ", Toast.LENGTH_SHORT).show();
        } catch (IOException e) {
            Log.e("FileSave", "CDM - IOException", e);
            Toast.makeText(this, "Errore saving file", Toast.LENGTH_LONG).show();
        }
    }
}

引用的类是:RaccoltaPunti.java

public class RaccoltaPunti {

    private String nomeRaccolta;
    private String nomePromoter;
    private String numeroTessera;
    private Long puntiPusseduti;
    private String dataScadenzaPunti;
    private String sitoWeb;
    private String sitoWebUsername;

        // constructor, getters and setters…….
}

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Answer 1

• 如果要保存列表，RaccoltaPunti 必须是Serializable。