objective c NSArray to NSString : Server side is java:
First create a string 'Hello world.' for example, and then use java code to convert this string to be a byte array, then send to ios client.
My ios client use NSStream to read the data, and got the array. 
Now I want to convert this array to be the string  'Hello world'.

How to do that? 
I have tried to convert the array to nsdata and then to nsstring, but it fails.
And also I try to convert the array to a string ,but it seems to convert the number in array to be a string number instead of my expected string 'Hello world'.