CharSequence VS String in Java ?

Question

Programming in Android, most of the text values are expected in CharSequence.

Why is that ? What is the benefit and what are the main impacts of using CharSequence over String ?

What are the main differences, and what issues are expected, while using them, and converting from one to another ?

Answer 1

Strings are CharSequences, so you can just use Strings and not worry. Android is merely trying to be helpful by allowing you to also specify other CharSequence objects, like StringBuffers.

Answer 2

In general using an interface allows you to vary the implementation with minimal collateral damage. Although java.lang.String are super popular it may be possible that in certain contexts one may want to use another implementation. By building the API around CharSequences rather than Strings the code gives one the opportunity to do that.

Answer 3

I believe it is best to use CharSequence. The reason is that String implements CharSequence, therefore you can pass a String into a CharSequence, HOWEVER you cannot pass a CharSequence into a String, as CharSequence doesn't not implement String. ALSO, in Android the EditText.getText() method returns an Editable, which also implements CharSequence and can be passed easily into one, while not easily into a String. CharSequence handles all!