Question

As per the API, the getText() method of EditText returns Editable. What was the purpose of it? It could simply have been a String return type?

And as per the Editable API:

This is the interface for text whose content and markup can be changed (as opposed to immutable text like Strings).

To achieve immutable functionality, why not use StringBuilder or StringBuffer instead?

Answer 1

public interface Editable implements GetChars, Spannable, Appendable, CharSequence

Amoung other features, Editable retains Spannable data which Strings and StringBuilders cannot do.