Is using ByteArray.writeObject() a good way to save state?

Hi All,

Here (below) is some code that I'm currently using for this. I originally posted this on another thread, but it's more appropriate to put it here.

I haven't tested it thoroughly yet, but it seems to work so far.

Also, in the other thread, ASWC offered some feedback. Here it is with my responses:

> This should work without problem as long as you are saving primitive values but here's the question,

> is saving only primitive values then why would you need a dictionary? If you need a dictionary then

> you might save complex values, if you save complex values then you are required to register their

> classes to be able to save/retrieve them. Are you saving complex objects and are you correctly

> using RegisterClassAlias?

Currently the only complex values that I'm using are Arrays, and they will only hold primitive values or other Arrays. I'm assuming that I don't need to register Array. But, as I said, I haven't fully tested this yet.

Are you suggesting that I could simply use Object, instead of Dictionary? If so, this makes sense. I'm not sure why I'm using Dictionary. 

Also, it would probably be a good idea to do some type-checking in setProperty() to enforce the limited types that this class is designed to support. This would help me to notice, years from now, if/when I start to save custom complex objects, and remind me that I need to use RegisterClassAlias.

Douglas

Here's the code I'm using ... I don't see any option in this forum's editor that will allow me to prevent formatting - indents etc. - from getting munged - so, sorry about the lousy formatting - and does anyone know how to insert code into these threads in a way that prevents this sad munging?

public class ByteArrayPersistenceManager {

   private var _initialized:Boolean;

   private var _persistenceDict:Dictionary;

   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  //
  // Public Methods
  //
  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

   public function ByteArrayPersistenceManager() {

   initializeIfNeeded();

  }

   public function setProperty(key:String, value:Object):void {

   initializeIfNeeded();

   if (_persistenceDict != null)

   _persistenceDict[key] = value;

  }

   public function getProperty(key:String):Object {

   initializeIfNeeded();

   if (_persistenceDict != null) {

   if (_persistenceDict.hasOwnProperty(key)) {

   return _persistenceDict[key];

  }

   else {

   return null;

  }

  }

   else {

   return null;

  }

  }

   public function save():Boolean {

   if (_initialized) {

   try {

   var fs:FileStream = new FileStream();

   var file:File = File.applicationStorageDirectory.resolvePath(getFilePath());

   fs.open(file, FileMode.WRITE);

   var byteArray:ByteArray = new ByteArray();

   byteArray.writeObject(_persistenceDict);

   fs.writeBytes(byteArray);

   fs.close()

  }

   catch (e:Error) {

  Log.error("ByteArrayPersistenceManager.save() - save failed: " + e.message);

   return false;

  }

   return true;

  }

   else {

  Log.error("ByteArrayPersistenceManager.save() - instance not initialized");

   return false;

  }

  }

   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  //
  // Private Methods
  //
  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

   private function initializeIfNeeded():void {

   if (!_initialized)

   load();

  }

   private function getFilePath():String {

   var result:String = Constant.FILEPATHINFO__PERSISTENCE_FOLDER_NAME + File.separator + Constant.FILEPATHINFO__PERSISTENCE_FILE_FILE_NAME;

   return result;

  }

   private function load():Boolean {

   try {

   var file:File = File.applicationStorageDirectory.resolvePath(getFilePath());

   if (file.exists) {

   var fs:FileStream = new FileStream();

   fs.open(file, FileMode.READ);

   var byteArray:ByteArray = new ByteArray();

   fs.readBytes(byteArray);

   fs.close();

   _persistenceDict = Dictionary(byteArray.readObject());

  }

   else {

   _persistenceDict = new PersistenceDict();

  }

   _initialized = true;

  }

   catch (e:Error) {

  Log.error("ByteArrayPersistenceManager.load() - load failed: " + e.message);

  }

   return _initialized;

  }

}

}