Thanks Yadukishore!
I guess the link you provided is for practice of:- HDP Certified Developer (HDCDP): for Hadoop developers using frameworks like Pig, Hive, Sqoop and Flume. However, I am looking for practice test for
Hortonworks Certified Apache Hadoop Java Developer: for developers who design, develop and architect Hadoop-based solutions written in the Java programming language. The exam details link is no where specifying about Practice test 
http://hortonworks.com/training/hadoop-2-0-javadeveloper-certification-2/