org.apache.cassandra.service.pager

Class SliceQueryPager

java.lang.Object

org.apache.cassandra.service.pager.SliceQueryPager

All Implemented Interfaces:

QueryPager, SinglePartitionPager

public class SliceQueryPager
extends java.lang.Object
implements SinglePartitionPager

Pager over a SliceFromReadCommand.

Field Summary

Fields

Modifier and Type	Field and Description
protected CFMetaData	cfm
protected IDiskAtomFilter	columnFilter

Method Summary

Methods

Modifier and Type	Method and Description
ColumnCounter	columnCounter()
protected boolean	containsPreviousLast(Row first)
java.util.List<Row>	fetchPage(int pageSize) Fetches the next page.
protected static Column	firstColumn(ColumnFamily cf)
boolean	isExhausted() Whether or not this pager is exhausted, i.e.
protected boolean	isReversed()
java.nio.ByteBuffer	key()
protected static Column	lastColumn(ColumnFamily cf)
int	maxRemaining() The maximum number of cells/CQL3 row that we may still have to return.
protected java.util.List<Row>	queryNextPage(int pageSize, ConsistencyLevel consistencyLevel, boolean localQuery)
protected boolean	recordLast(Row last)
protected void	restoreState(int remaining, boolean lastWasRecorded)
PagingState	state() Get the current state of the pager.
long	timestamp()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.cassandra.service.pager.SinglePartitionPager

columnCounter

Methods inherited from interface org.apache.cassandra.service.pager.QueryPager

fetchPage, isExhausted, maxRemaining

Field Detail

cfm

protected final CFMetaData cfm

columnFilter

protected final IDiskAtomFilter columnFilter

Method Detail

key

public java.nio.ByteBuffer key()

Specified by:

key in interface SinglePartitionPager

state

public PagingState state()

Description copied from interface: QueryPager

Get the current state of the pager. The state can allow to restart the paging on another host from where we are at this point.

Specified by:

state in interface QueryPager

Returns:

the current paging state. Will return null if paging is at the beginning. If the pager is exhausted, the result is undefined.

queryNextPage

protected java.util.List<Row> queryNextPage(int pageSize,
                                ConsistencyLevel consistencyLevel,
                                boolean localQuery)
                                     throws RequestValidationException,
                                            RequestExecutionException

Throws:

RequestValidationException

RequestExecutionException

containsPreviousLast

protected boolean containsPreviousLast(Row first)

recordLast

protected boolean recordLast(Row last)

isReversed

protected boolean isReversed()

fetchPage

public java.util.List<Row> fetchPage(int pageSize)
                              throws RequestValidationException,
                                     RequestExecutionException

Description copied from interface: QueryPager

Fetches the next page.

Specified by:

fetchPage in interface QueryPager

Parameters:

pageSize - the maximum number of elements to return in the next page.

Returns:

the page of result.

Throws:

RequestValidationException

RequestExecutionException

restoreState

protected void restoreState(int remaining,
                boolean lastWasRecorded)

isExhausted

public boolean isExhausted()

Description copied from interface: QueryPager

Whether or not this pager is exhausted, i.e. whether or not a call to fetchPage may return more result.

Specified by:

isExhausted in interface QueryPager

Returns:

whether the pager is exhausted.

maxRemaining

public int maxRemaining()

Description copied from interface: QueryPager

The maximum number of cells/CQL3 row that we may still have to return. In other words, that's the initial user limit minus what we've already returned (note that it's not how many we *will* return, just the upper limit on it).

Specified by:

maxRemaining in interface QueryPager

timestamp

public long timestamp()

columnCounter

public ColumnCounter columnCounter()

firstColumn

protected static Column firstColumn(ColumnFamily cf)

lastColumn

protected static Column lastColumn(ColumnFamily cf)