Feature: Corrected the link for Callback link.

Author: syedumerahmedcode

README.md

@@ -78,7 +78,7 @@ Pure functional programming has a set of rules that one must follow:
 
 A callback is some code that you pass to a given method, so that it can be called at a later time.
 
-**Reference:** The source code for the Callback is present in [Callback.java](https://github.com/syedumerahmedcode/prefix/blob/master/trie/src/main/java/com/umer/javafunctional/callback/Callback.java) class.
+**Reference:** The source code for the Callback is present in [Callback.java](https://github.com/syedumerahmedcode/java-functional-programming/blob/master/trie/src/main/java/com/umer/javafunctional/callback/Callback.java) class.
 
 ## Explanation Consumer