Java: Getting object associated with enum

Question

I have an ArrayList full of custom objects. I need to save this ArrayList to a Bundle and then retrieve it later.

Having failed with both Serializable and Parcelable, I'm now simply trying to somehow save the objects that are associated with the indexes in the ArrayList, then checking these when restoring the Bundle and adding the objects back in.

What I have is something like this:

When saving the Bundle:

    //Create temporary array of the same length as my ArrayList
    String [] tempStringArray = new String[myList.size()];

    //Convert the enum to a string and save it in the temporary array
    for (int i = 0; i<myList.size();i++){
                tempStringArray [i] = myList.get(i).getType();  //returns the enum in string form
    }

    //Write this to the Bundle
    bundle.putStringArray("List", tempStringArray);

So I now have an array of strings representing the enum types of the objects that were originally in the ArrayList.

So, when restoring the Bundle, what I'm trying is something like this:

//Temporary string array
String[] tempStringArray = savedState.getStringArray("List");

//Temporary enum array
ObjectType[] tempEnumArray = new ObjectType[tempStringArray.length];

for (int i = 0; i<tempStringArray.length;i++){
    tempEnumArray[i]=ObjectType.valueOf(tempEnemies[i]);
}

So, now I have the enum type of each item that was originally in the ArrayList.

What I'm now trying to do now, is something like (would go inside the for loop above):

myList.add(tempEnumArray[i].ObjectTypeThisEnumRefersTo());

Obviously the "ObjectTypeThisEnumRefersTo()" method above doesn't exist but this is ultimately, what I'm trying to find out. Is this possible or perhaps there is some other way of doing this?

Answer 1

To get an enum value of the enum type Enemy from a string, use

Enemy.valueOf(String).

Enemy.valueOf("SPIDER") would return Enemy.SPIDER, provided your enum looks like

enum Enemy { SPIDER,  BEE};

EDIT: It turns out Zippy also had a fixed set of Enemy objects, each mapped to each value of EnemyType, and needed a way to find an Enemy from a given EnemyType. My suggestion is to create a

HashMap<EnemyType, Enemy> 

and put all the objects in there upon creation, then at deserialization convert strings to enum values and enum values to Enemy objects using the hashmap.

It later occurred to me though that depending on how much logic you have in Enemy, you might want to consider scrapping either Enemy or EnemyType and combine them into one parameterized enum, similar to the example with Planet over here:http://docs.oracle.com/javase/tutorial/java/javaOO/enum.html That would spare you from having to go two steps from a string to your final object and simplify things a bit as you wouldn't need any hashmap after all.