Should I need to learn Hadoop before learning HBase?

Not necessarily..But, yes, having atleast the basics of Hadoop will help you in understanding HBase better as would understanding ZooKeeper would do(Still  understanding Hadoop will probably yield more benefits than ZooKeeper to learn HBase). Orielly's Definitive Guide is a good place to start learning.

In a broad sense, you'll hear about the fact that HBase is a noSQL database that enables random access to BigData. The HDFS is designed to be more for batch systems and are not fit for random reads of data for real time applications. Now to understand and grasp the how aspect of HDFS and MapReduce and to get a command over what is the justification for the existence of HBase, I would strongly recommend to try and learn about the Hadoop ecosystem. The details are involved, all the while, very intriguing. Two books that you could refer are (for both Hadoop and Hbase) :- Chuck Lam - Hadoop in Action Hadoop The Definitive Guide.

Hadoop is an ecosystem constituting of various components and HBase is in conjunction with Hadoop. As a Java developer, it will make more of a sense to look for "Hadoop Developer" courses, which needs you to learn Hadoop MapReduce as untimately you will be asked to write MapReduce programs to solve business scenarios.

Hadoop is method of many data science projects. New technologies grow-up on finest of Hadoop are released all the time, and it can be difficult to keep upHadoop and big data certification training will be very helpful for passing the-professional Certification exam on Hadoop and advanced data analytics. For More better Info You can Visit ThisLink https://goo.gl/rrChA2 with the wide array of tools at your-clearance, so here is a list some of the better neededapache Hadoop the official distribution.Apache Ambari , a software package for managing Hadoop clustersHDFC Reduce the basic framework for splitting data across a cluster underpinning Hadoop.Apache H-base, a table-oriented database built on top of Hadoop.Apache Hive a data warehouse built on top of Hadoop that makes data accessible through an SQL-like language.·Apache sqoop , a tool for transferring data between Hadoop and other data stores.Apache Pig, a platform for running code on data in Hadoop in parallel.Zookeeper, a tool for configuring and synchronizing Hadoop clusters.No SQL, a type of database that breaks from traditional relational database management systems using SQL. Popular No SQL databases include Cassandra, riak, and MongoDB.Apache mahout a machine learning library designed to run on data stored in Hadoop.apache solar , a tool for indexing text data that integrates well with Hadoop.Apache avero, a data serialization system.oozie, a work flow manager for the Apache tool chain.Gis tools, a set of tools to help manage geographical components of your dataApache Flume, a systemfor collecting log data using HDFS.SQL on Hadoop, some ofthe most popular options include: Apache Hive, Cloudera Impala, Presto(Facebook), Shark, Apache Drill, EMC/Pivotal HAWQ, Big SQL by IBM, ApachePhoenix (for H Base), Apache TajoClouds, managedservers and services that remove the hassle of running your own infrastructureApache Spark a new way to run algorithms even faster on Hadoop data.