org.hypergraphdb.query

Class SimpleValueCondition

java.lang.Object

org.hypergraphdb.query.SimpleValueCondition

All Implemented Interfaces:

HGAtomPredicate, HGQueryCondition

Direct Known Subclasses:

AtomPartCondition, AtomValueCondition

public abstract class SimpleValueCondition
extends Object
implements HGQueryCondition, HGAtomPredicate

Basic class for conditions examining individual primitive values.

Author:

Borislav Iordanov

Field Summary

Fields

Modifier and Type	Field and Description
protected ComparisonOperator	operator
protected Ref<Object>	value

Constructor Summary

Constructors

Constructor and Description
SimpleValueCondition()
SimpleValueCondition(Object value)
SimpleValueCondition(Object value, ComparisonOperator operator)
SimpleValueCondition(Ref<Object> value, ComparisonOperator operator)

Method Summary

Methods

Modifier and Type	Method and Description
protected boolean	compareToValue(HyperGraph graph, Object x) We are using the standard Java java.lang.Comparable interface here on the value parameter.
boolean	equals(Object x)
ComparisonOperator	getOperator()
Object	getValue()
Ref<Object>	getValueReference()
int	hashCode()
void	setOperator(ComparisonOperator operator)
void	setValue(Object value)
void	setValueReference(Ref<Object> value)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.hypergraphdb.query.HGAtomPredicate

satisfies

Field Detail

value

protected Ref<Object> value

operator

protected ComparisonOperator operator

Constructor Detail

SimpleValueCondition

public SimpleValueCondition()

SimpleValueCondition

public SimpleValueCondition(Object value)

SimpleValueCondition

public SimpleValueCondition(Object value,
                    ComparisonOperator operator)

SimpleValueCondition

public SimpleValueCondition(Ref<Object> value,
                    ComparisonOperator operator)

Method Detail

compareToValue

protected boolean compareToValue(HyperGraph graph,
                     Object x)

We are using the standard Java java.lang.Comparable interface here on the value parameter. The passed in type is ignored, but is part of the method signature because it is still not clear how exactly value orderings are to be treated. All Java primitive types are comparable and our primitive types are nothing more than the Java primitive types. Perhaps we need an "ordered" interface for atom types. Of course values can always implement the java.lang.Comparable, but this breaks HyperGraph paradigm where such semantics are defined by the types, not their values.

getValueReference

public Ref<Object> getValueReference()

setValueReference

public void setValueReference(Ref<Object> value)

getValue

public Object getValue()

setValue

public void setValue(Object value)

getOperator

public ComparisonOperator getOperator()

setOperator

public void setOperator(ComparisonOperator operator)

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object x)

Overrides:

equals in class Object