Package org.apache.hadoop.hbase.client.example

Class MultiThreadedClientExample

java.lang.Object

org.apache.hadoop.conf.Configured

org.apache.hadoop.hbase.client.example.MultiThreadedClientExample

All Implemented Interfaces:

org.apache.hadoop.conf.Configurable, org.apache.hadoop.util.Tool

@Private
public class MultiThreadedClientExample
extends org.apache.hadoop.conf.Configured
implements org.apache.hadoop.util.Tool

Example on how to use HBase's Connection and Table in a multi-threaded environment. Each table is a light weight object that is created and thrown away. Connections are heavy weight objects that hold on to zookeeper connections, async processes, and other state.

 Usage:
 bin/hbase org.apache.hadoop.hbase.client.example.MultiThreadedClientExample testTableName 500000
 

The table should already be created before running the command. This example expects one column family named d.

This is meant to show different operations that are likely to be done in a real world application. These operations are:

• 30% of all operations performed are batch writes. 30 puts are created and sent out at a time. The response for all puts is waited on.
• 20% of all operations are single writes. A single put is sent out and the response is waited for.
• 50% of all operations are scans. These scans start at a random place and scan up to 100 rows.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MultiThreadedClientExample.ReadExampleCallable	Class to show how to scan some rows starting at a random location.
static class	MultiThreadedClientExample.SingleWriteExampleCallable	Class to show how to send a single put.
static class	MultiThreadedClientExample.WriteExampleCallable	Class that will show how to send batches of puts at the same time.

Field Summary

Fields

Modifier and Type	Field	Description
private static final int	DEFAULT_NUM_OPERATIONS
private static final byte[]	FAMILY	The name of the column family.
private final ExecutorService	internalPool
private static final org.slf4j.Logger	LOG
private static final byte[]	QUAL	For the example we're just using one qualifier.
private final int	threads

Constructor Summary

Constructors

Constructor	Description
MultiThreadedClientExample()

Method Summary

Modifier and Type	Method	Description
static void	main(String[] args)
int	run(String[] args)
private void	warmUpConnectionCache(Connection connection, TableName tn)

Methods inherited from class org.apache.hadoop.conf.Configured

getConf, setConf

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.hadoop.conf.Configurable

getConf, setConf

Field Details

LOG

private static final org.slf4j.Logger LOG

DEFAULT_NUM_OPERATIONS

private static final int DEFAULT_NUM_OPERATIONS

See Also:

• Constant Field Values

FAMILY

private static final byte[] FAMILY

The name of the column family. d for default.

QUAL

private static final byte[] QUAL

For the example we're just using one qualifier.

internalPool

private final ExecutorService internalPool

threads

private final int threads

Constructor Details

MultiThreadedClientExample

public MultiThreadedClientExample()
                           throws IOException

Throws:

IOException

Method Details

run

public int run(String[] args)
        throws Exception

Specified by:

run in interface org.apache.hadoop.util.Tool

Throws:

Exception

warmUpConnectionCache

private void warmUpConnectionCache(Connection connection,
 TableName tn)
                            throws IOException

Throws:

IOException

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception