通过参数确定转换和返回类型

Question

I really don't know what to look for and if this is even possible. I am trying to code a dynamic Fileloader.

This is the code:

public static Serializable loadSerializable(Context context,
        String filename, Object object) {
    final String DEBUGTAG = "Loading data" ;
    Serializable serializable = null;
    ObjectInputStream oin = null;
    try {
        File file = new File(context.getFilesDir(), filename);
        FileInputStream in = new FileInputStream(file);
        oin = new ObjectInputStream(in);
        Object readElement = oin.readObject();
        serializable = (Serializable) readElement; // here I want dynamic casting
        Log.d(DEBUGTAG, "Success : " + filename);
    } catch (FileNotFoundException e) {
        Log.d(DEBUGTAG, "File not found");
    } catch (StreamCorruptedException e) {
        Log.d(DEBUGTAG, "Stream Corrupted");
    } catch (IOException e) {
        Log.d(DEBUGTAG, "IOException");
    } catch (ClassNotFoundException e) {
        Log.d(DEBUGTAG, "Class not Found");
    } catch (NullPointerException e) {
        Log.d(DEBUGTAG, "NullPointer - File does not exist yet");
    } finally {
        if (oin != null)
            try {
                oin.close();
            } catch (IOException e) {
                Log.d(DEBUGTAG, "IOException - Stream not closed");
            }
    }
    return serializable;
}

What I want to do now is instead of creating a new method for every single object I want to use the 3rd argument (object or whatever) for the type casting.

So I could write String myString = loadSerializable(this, test.dat, String) or ArrayList<Fragment> = loadSerializable(this, test.dat, ArrayList<Fragment>) and so on.... Help appreciated

Answer 1

Something like

public static <T> T loadSerializable(Context context, String filename) {
    // ...
    T t = (T) readElement;
    // ...
    return t;
}