com.bigdata.striterator

Class AbstractKeyOrder<E>

java.lang.Object

com.bigdata.striterator.AbstractKeyOrder<E>

All Implemented Interfaces:

IKeyOrder<E>

Direct Known Subclasses:

LexiconKeyOrder, R.KeyOrder, SPOKeyOrder

public abstract class AbstractKeyOrder<E>
extends Object
implements IKeyOrder<E>

Abstract base class provides default behavior for generating keys for a given index order.

Author:

Bryan Thompson

Constructor Summary

Constructors

Constructor and Description
AbstractKeyOrder()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	appendKeyComponent(IKeyBuilder keyBuilder, int index, Object keyComponent) Encodes an value into the key.
byte[]	getFromKey(IKeyBuilder keyBuilder, IPredicate<E> predicate) Return the inclusive lower bound which would be used for a query against this IKeyOrder for the given IPredicate.
byte[]	getKey(IKeyBuilder keyBuilder, E element) Return the key for an element of the relation.
byte[]	getToKey(IKeyBuilder keyBuilder, IPredicate<E> predicate) Return the exclusive upper bound which would be used for a query against this IKeyOrder for the given IPredicate.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.bigdata.striterator.IKeyOrder

getComparator, getIndexName, getKeyArity, getKeyOrder

Constructor Detail

AbstractKeyOrder

public AbstractKeyOrder()

Method Detail

getKey

public byte[] getKey(IKeyBuilder keyBuilder,
            E element)

Return the key for an element of the relation. FIXME This needs to be reconciled with ITupleSerializer.serializeKey(Object). For example, this does not play well with the DefaultTupleSerializer.

Specified by:

getKey in interface IKeyOrder<E>

Parameters:

keyBuilder - The object which will be used to construct the key.

element - An element for the associated relation.

Returns:

The key for the index associated with this IKeyOrder.

getFromKey

public byte[] getFromKey(IKeyBuilder keyBuilder,
                IPredicate<E> predicate)

Description copied from interface: IKeyOrder

Return the inclusive lower bound which would be used for a query against this IKeyOrder for the given IPredicate.

Specified by:

getFromKey in interface IKeyOrder<E>

Parameters:

keyBuilder - The object which will be used to construct the key.

predicate - A predicate describing bound and unbound fields for the key.

Returns:

The key corresponding to the inclusive lower bound for a query against that IPredicate.

getToKey

public byte[] getToKey(IKeyBuilder keyBuilder,
              IPredicate<E> predicate)

Description copied from interface: IKeyOrder

Return the exclusive upper bound which would be used for a query against this IKeyOrder for the given IPredicate.

Specified by:

getToKey in interface IKeyOrder<E>

Parameters:

keyBuilder - The object which will be used to construct the key.

predicate - A predicate describing bound and unbound fields for the key.

Returns:

The key corresponding to the exclusive upper bound for a query against that IPredicate.

appendKeyComponent

protected void appendKeyComponent(IKeyBuilder keyBuilder,
                      int index,
                      Object keyComponent)

Encodes an value into the key. This implementation uses the default behavior of IKeyBuilder. If you need to specialize how a value gets encoded into the key then you can override this method.