com.amazon.titan.diskstorage.dynamodb

Class QueryWorker

java.lang.Object

com.amazon.titan.diskstorage.dynamodb.PaginatingTask<QueryRequest,QueryResultWrapper>

com.amazon.titan.diskstorage.dynamodb.QueryWorker

All Implemented Interfaces:

java.util.concurrent.Callable<QueryResultWrapper>

Direct Known Subclasses:

QueryWithLimitWorker

public class QueryWorker
extends PaginatingTask<QueryRequest,QueryResultWrapper>

QueryWorker iterates through pages of DynamoDB Query results.

Author:

Alexander Patrikalakis

Field Summary

Fields inherited from class com.amazon.titan.diskstorage.dynamodb.PaginatingTask

delegate

Constructor Summary

Constructors

Constructor and Description
QueryWorker(DynamoDBDelegate delegate, QueryRequest request, com.thinkaurelius.titan.diskstorage.StaticBuffer titanKey)

Method Summary

Methods

Modifier and Type	Method and Description
protected java.util.List<java.util.Map<java.lang.String,AttributeValue>>	getFinalItemList()
protected QueryResultWrapper	getMergedPages() Merges all the pages iterated through in this instance and returns them
QueryRequest	getRequest()
int	getReturnedCount()
int	getScannedCount()
boolean	hasNext()
protected void	markComplete()
QueryResultWrapper	next() moves the iterator to the next page in preparation for another hasNext/processPage call

Methods inherited from class com.amazon.titan.diskstorage.dynamodb.PaginatingTask

call, getPagesProcessed

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryWorker

public QueryWorker(DynamoDBDelegate delegate,
           QueryRequest request,
           com.thinkaurelius.titan.diskstorage.StaticBuffer titanKey)

Method Detail

next

public QueryResultWrapper next()
                        throws com.thinkaurelius.titan.diskstorage.BackendException

Description copied from class: PaginatingTask

moves the iterator to the next page in preparation for another hasNext/processPage call

Specified by:

next in class PaginatingTask<QueryRequest,QueryResultWrapper>

Throws:

com.thinkaurelius.titan.diskstorage.BackendException

hasNext

public boolean hasNext()

Specified by:

hasNext in class PaginatingTask<QueryRequest,QueryResultWrapper>

Returns:

true if there are more pages to process and false if done

getScannedCount

public int getScannedCount()

getReturnedCount

public int getReturnedCount()

getRequest

public QueryRequest getRequest()

markComplete

protected void markComplete()

getMergedPages

protected QueryResultWrapper getMergedPages()

Description copied from class: PaginatingTask

Merges all the pages iterated through in this instance and returns them

Specified by:

getMergedPages in class PaginatingTask<QueryRequest,QueryResultWrapper>

Returns:

a merged view of all the paged results of this iterator

getFinalItemList

protected java.util.List<java.util.Map<java.lang.String,AttributeValue>> getFinalItemList()