Why does Android's Bundle API accept ArrayLists rather than Lists

Question

I'm new to Android and while going through a tutorial on saving Activity state to a Bundle, I noticed that instead of accepting the more generic List interface, Bundle's put methods are expecting ArrayLists.

Example:

Bundle.putCharSequenceArrayList(key, value)
Bundle.putIntegerArrayList(key, value)
Bundle.putParcelableArrayList(key, value)
Bundle.putStringArrayList(key, value)

Most of us are familiar with item 52 of Effective Java suggesting that objects must be refered to by their interface, so I am wondering what was the reason behind this API decision.

Is ArrayList perhaps the preferred list implementation in Android?

score 9 · Accepted Answer · answered Jul 24 '13 at 04:10

9

Just a guess: Maybe Bundele-content must be be serializable and not every Lists implementation is serializable.

From sdk-doc public Bundle.Bundle (ClassLoader)

  Constructs a new, empty Bundle that uses a specific 
  ClassLoader for instantiating Parcelable and Serializable objects.

answered Jul 24 '13 at 04:10

k3b

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makes sense! i'll wait a while more in case someone has a definitive answer. – jramoyo Jul 24 '13 at 05:33
the more I go through the tutorial, the more this answer makes sense. so I am accepting it :-) – jramoyo Jul 24 '13 at 10:00

Why does Android's Bundle API accept ArrayLists rather than Lists

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