org.hypergraphdb.query

Class AtomTypeCondition

java.lang.Object

org.hypergraphdb.query.AtomTypeCondition

All Implemented Interfaces:

HGAtomPredicate, HGQueryCondition, TypeCondition

public class AtomTypeCondition
extends Object
implements HGQueryCondition, HGAtomPredicate, TypeCondition

An AtomTypeCondition examines the type of a given atom and evaluates to true or false depending on whether the type of the atom matches exactly (i.e. has the same type handle) as that of the condition. Note that this condition looks at the concrete type of the atom and ignores and sub-typing relationships.

The type can be specified either as a HyperGraph handle or as a Java class. In the latter, the corresponding HyperGraph will be retrieved at appropriate times. However, those two properties overlap each other, in the sense the you can set one or the other, but not both at the same time. If you set the type as a Java class, the corresponding HGHandle will be retrieved every time it is needed. In particular, if this is used as a filtering condition applied iteratively over a large result set, performance will be hurt by the extra step.

Author:

Borislav Iordanov

Constructor Summary

Constructors

Constructor and Description
AtomTypeCondition()
AtomTypeCondition(Class<?> javaClass)
AtomTypeCondition(HGHandle typeHandle)
AtomTypeCondition(Ref<?> typeRef) Construct a new atom type condition.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object x)
Class<?>	getJavaClass()
HGHandle	getTypeHandle()
HGHandle	getTypeHandle(HyperGraph graph)
Ref<?>	getTypeReference()
int	hashCode()
boolean	satisfies(HyperGraph hg, HGHandle value) Check whether a given Object satisfies this query condition.
void	setJavaClass(Class<?> c)
void	setTypeHandle(HGHandle handle)
void	setTypeReference(Ref<?> type)
String	toString()
HGHandle	typeHandleIfAvailable(HyperGraph graph)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

AtomTypeCondition

public AtomTypeCondition()

AtomTypeCondition

public AtomTypeCondition(Ref<?> typeRef)

Construct a new atom type condition.

Parameters:

typeRef - A Ref to a Java Class or a HGHandle.

AtomTypeCondition

public AtomTypeCondition(Class<?> javaClass)

AtomTypeCondition

public AtomTypeCondition(HGHandle typeHandle)

Method Detail

typeHandleIfAvailable

public HGHandle typeHandleIfAvailable(HyperGraph graph)

setJavaClass

public void setJavaClass(Class<?> c)

getJavaClass

public Class<?> getJavaClass()

setTypeHandle

public void setTypeHandle(HGHandle handle)

getTypeHandle

public HGHandle getTypeHandle()

getTypeHandle

public HGHandle getTypeHandle(HyperGraph graph)

getTypeReference

public Ref<?> getTypeReference()

Specified by:

getTypeReference in interface TypeCondition

setTypeReference

public void setTypeReference(Ref<?> type)

satisfies

public boolean satisfies(HyperGraph hg,
                HGHandle value)

Description copied from interface: HGAtomPredicate

Check whether a given Object satisfies this query condition.

Specified by:

satisfies in interface HGAtomPredicate

Parameters:

hg - The HyperGraph instance.

value - The atom on which to test the query condition.

Returns:

true if the passed in parameter satisfies the condition and false otherwise.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object x)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object