org.rhq.cassandra.schema

Class PopulateCacheIndex

java.lang.Object

org.rhq.cassandra.schema.PopulateCacheIndex

All Implemented Interfaces:

Step

public class PopulateCacheIndex
extends Object
implements Step

This is a custom step that performs data migration for users migrating to RHQ 4.11 from either 4.9 or 4.10. Before 4.11 we had the numeric data tables and the metrics_index table which serves as a custom index. In 4.11, two new tables are being added - metrics_cache and metrics_cache_index. The metrics_index table is being dropped. This class performs several tasks.

• Migrates data from metrics_index to metrics_cache
• Delete rows in metrics_index of migrated data
• Deactivates the metrics cache (if necessary)
• Drops the metrics_index table

A row in metrics_index is deleted only after successfully migrating the data into metrics_cache_index. And at the end of the process, metrics_index is dropped only if there are no errors. If there are any errors inserting data into metrics_cache_index, an exception is thrown which will cause the installation/upgrade to fail. This allows for the upgrade to be retried so that any remaining data in metrics_index can be migrated.

Author:

John Sanda

Constructor Summary

Constructors

Constructor and Description
PopulateCacheIndex()

Method Summary

Methods

Modifier and Type	Method and Description
void	bind(Properties properties) Bind the set of provided properties to the input step.
void	execute() Perform the actual work of the step.
void	setSession(com.datastax.driver.core.Session session) Invoked prior to Step.execute().

Methods inherited from class java.lang.Object

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

Constructor Detail

PopulateCacheIndex

public PopulateCacheIndex()

Method Detail

setSession

public void setSession(com.datastax.driver.core.Session session)

Description copied from interface: Step

Invoked prior to Step.execute(). Note that this is the same session used by SchemaManager and it should not be closed.

Specified by:

setSession in interface Step

bind

public void bind(Properties properties)

Description copied from interface: Step

Bind the set of provided properties to the input step. The text should have all the variable to be bound in %variable_name% form.

This method should be called even if no properties are provided because it will throw a runtime exception if the text contains properties that are expected to be bound but the list of variable is either empty or does not contain them.

This method is invoked prior to Step.execute()

Specified by:

bind in interface Step

Parameters:

properties - properties to bind

execute

public void execute()

Description copied from interface: Step

Perform the actual work of the step.

Specified by:

execute in interface Step