Running maven build HBase
application in MapR
Step by step guide to build a simple HBase application using
Maven and execute the same in a MapR cluster.
Assumption: We already have a MapR cluster up and running
with Hbase and other required components.
Perform the following
steps:
Go into the following folder and create a
directory for maven
cd /home/mapr
mkdir maven
Download and install maven
cd maven
tar -xvf apache-maven-3.3.9-bin.tar.gz
Set maven home
export
M2_HOME=/home/mapr/maven/apache-maven-3.3.9
export PATH=${M2_HOME}/bin:${PATH}
Create a folder for the sample HBase application
mkdir -p java-jobs/hbase
cd java-jobs/hbase
Generate a sample maven project
mvn archetype:generate
-DgroupId=com.ajames.hbase.examples -DartifactId=hbaseapp
-DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false
Modify the pom.xml file to add the mapr
repository details
cd hbaseapp/
vi pom.xml
Add mapr repository details:
<repositories>
<repository>
<id>mapr-maven</id>
<url>http://repository.mapr.com/maven</url>
<releases><enabled>true</enabled></releases>
<snapshots><enabled>false</enabled></snapshots>
</repository>
</repositories>
Modify pom.xml file to add the HBase dependecy
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-client</artifactId>
<version>1.1.1-mapr-1602</version>
</dependency>
Create the sample application
cd
src/main/java/com/ajames/hbase/examples/
Sample code:
package com.ajames.hbase.examples;
import org.apache.hadoop.conf.Configuration;
import
org.apache.hadoop.hbase.HBaseConfiguration;
import
org.apache.hadoop.hbase.client.HTable;
import
org.apache.hadoop.hbase.client.Put;
import java.io.IOException;
/* Create table schema using following
command.
*
echo "create 'details','a','b'" | hbase shell
*/
public class HBaseDemo {
public
static void main(String[] args) throws IOException {
Configuration
conf = HBaseConfiguration.create();
HTable
table = new HTable(conf,"details");
Put
p1 = new Put("details1".getBytes());
byte[]
a = "a".getBytes();
byte[]
b = "b".getBytes();
p1.add(a,"c1".getBytes(),"First".getBytes());
p1.add(b,"c1".getBytes(),"Second".getBytes());
table.put(p1);
table.close();
}
}
Building the application
cd /home/mapr/java-jobs/hbase/hbaseapp
mvn clean package
Running the application
export HADOOP_CLASSPATH=`hbase
classpath`
[mapr@m52-d18-1 hbaseapp]$ hadoop
jar target/hbaseapp-1.0-SNAPSHOT.jar com.ajames.hbase.examples.HBaseDemo
16/09/26 21:08:01 INFO client.ConnectionFactory:
mapr.hbase.default.db unsetDB is neither MapRDB or HBase, set HBASE_MAPR mode
since mapr client is installed.
16/09/26 21:08:01 INFO client.ConnectionFactory:
ConnectionFactory receives mapr.hbase.default.db(unsetDB), set
clusterType(HBASE_MAPR), hbase_admin_connect_at_construction(false)
16/09/26 21:08:01 INFO client.ConnectionFactory:
ConnectionFactory creates a hbase connection!
16/09/26 21:08:02 INFO client.HTable: BufferedMutator Use
HBase ThreadPool
16/09/26 21:08:02 INFO zookeeper.RecoverableZooKeeper:
Process identifier=hconnection-0x66dd1d3 connecting to ZooKeeper
ensemble=10.10.72.147:5181,10.10.72.148:5181
16/09/26 21:08:02 INFO
client.ConnectionManager$HConnectionImplementation: Closing zookeeper
sessionid=0x15767d869180047
Verify the HBase table
hbase shell
hbase(main):001:0> scan 'details'
ROW COLUMN+CELL
details1
column=a:c1, timestamp=1474938482964, value=First
details1
column=b:c1, timestamp=1474938482964, value=Second
1 row(s) in 0.5730 seconds
