com.amazon.carbonado.qe
Class KeyQueryExecutor<S extends Storable>

java.lang.Object
  com.amazon.carbonado.qe.AbstractQueryExecutor<S>
      com.amazon.carbonado.qe.KeyQueryExecutor<S>

All Implemented Interfaces:

QueryExecutor<S>

public class KeyQueryExecutor<S extends Storable>
extends AbstractQueryExecutor<S>

QueryExecutor which has a fully specified key, and so cursors produce at most one result.

Author:

Brian S O'Neill

Nested Class Summary

static interface

KeyQueryExecutor.Support<S extends Storable> Provides support for KeyQueryExecutor.

Constructor Summary

KeyQueryExecutor(KeyQueryExecutor.Support<S> support, StorableIndex<S> index, FilteringScore<S> score)

Method Summary

Cursor<S>	fetch(FilterValues<S> values) Returns a new cursor using the given filter values.
Filter<S>	getFilter() Returns the filter used by this QueryExecutor.
OrderingList<S>	getOrdering() Returns an empty list.
Class<S>	getStorableType() Returns the storable type that this executor operates on.
boolean	printPlan(Appendable app, int indentLevel, FilterValues<S> values) Prints the query plan to any appendable, if applicable.

Methods inherited from class com.amazon.carbonado.qe.AbstractQueryExecutor

count, fetchSlice, increaseIndent, indent, newline, printNative

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyQueryExecutor

public KeyQueryExecutor(KeyQueryExecutor.Support<S> support,
                        StorableIndex<S> index,
                        FilteringScore<S> score)

Parameters:

index - index to use, which may be a primary key index

score - score determines how best to utilize the index

Throws:

IllegalArgumentException - if any parameter is null or if index is not unique or if score is not a key match

Method Detail

getStorableType

public Class<S> getStorableType()

Description copied from interface: QueryExecutor

Returns the storable type that this executor operates on.

Specified by:

getStorableType in interface QueryExecutor<S extends Storable>

Overrides:

getStorableType in class AbstractQueryExecutor<S extends Storable>

fetch

public Cursor<S> fetch(FilterValues<S> values)
                                 throws FetchException

Description copied from interface: QueryExecutor

Returns a new cursor using the given filter values.

Throws:

FetchException

getFilter

public Filter<S> getFilter()

Description copied from interface: QueryExecutor

Returns the filter used by this QueryExecutor.

Returns:

query filter, never null

getOrdering

public OrderingList<S> getOrdering()

Returns an empty list.

Returns:

query ordering in an unmodifiable list

printPlan

public boolean printPlan(Appendable app,
                         int indentLevel,
                         FilterValues<S> values)
                  throws IOException

Description copied from interface: QueryExecutor

Prints the query plan to any appendable, if applicable.

values - optional

Returns:

false if not implemented

Throws:

IOException