be.SIRAPRISE.typeimplementations

Class IntervalIntersectOperatorImplementation

java.lang.Object

be.SIRAPRISE.typeimplementations.IntervalIntersectOperatorImplementation

All Implemented Interfaces:

AggregationOperatorImplementation, IntervalOperatorImplementation, OperatorImplementation_V0104, OperatorImplementation_V0105, java.io.Externalizable, java.io.Serializable

public final class IntervalIntersectOperatorImplementation
extends java.lang.Object
implements IntervalOperatorImplementation, AggregationOperatorImplementation

The implementation for the interval intersect operator for a specific underlying base type

Author:

Erwin Smout

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
IntervalIntersectOperatorImplementation(IntervalTypeImplementation intervalTypeImplementation, IntervalOverlapsOperatorImplementation overlapsOperatorImplementation) Creates the implementation object

Method Summary

Modifier and Type	Method and Description
ValueBuffer	executeOperator(java.util.LinkedList<ValueBuffer> args) Performs the actual logic of the operator.
java.lang.String[]	getArgumentTypeNames() An interval intersect operator takes two arguments that are both of the same interval type
ValueBuffer	getIdentityElement() The identity element of any interval intersect operator exists only if the base type underlying the interval type to which the intersect operator is applied, has a FIRST...() operator.
TypeDeclaration	getReturnTypeDeclaration() Gets the full type declaration of the type of the return value.
java.lang.String	getReturnTypeName() The return type of any interval intersect operator is the same as its argument types.
java.lang.String	getSignature() Gets the name of the operator implemented by this implementation object
boolean	isDeterministic() Tells whether the operator is deterministic with respect to the arguments of its invocations.
void	readExternal(java.io.ObjectInput in)
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class java.lang.Object

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

Constructor Detail

IntervalIntersectOperatorImplementation

public IntervalIntersectOperatorImplementation(IntervalTypeImplementation intervalTypeImplementation,
                                               IntervalOverlapsOperatorImplementation overlapsOperatorImplementation)

Creates the implementation object

Parameters:

intervalTypeImplementation - The IntervalTypeIplementation object of the arguments (and our own return of course)

overlapsOperatorImplementation - implementation of the overlaps operator for the same interval type

Method Detail

executeOperator

public ValueBuffer executeOperator(java.util.LinkedList<ValueBuffer> args)

Description copied from interface: OperatorImplementation_V0104

Performs the actual logic of the operator.

Specified by:

executeOperator in interface OperatorImplementation_V0104

Parameters:

args - the argument list. The list must hold as many ValueBuffer objects as there are arguments to the operator, and each ValueBuffer object holds a value for some argument to the operator. ValueBuffer objects on the list must appear in the same order as the operator argument declarations. Implementations have the option, but are not required, to do a check the conformance of the argument list (the argument count, notably) to the operator signature.

Returns:

A ValueBuffer object holding the result value of the operator execution in internal format.

getArgumentTypeNames

public java.lang.String[] getArgumentTypeNames()

An interval intersect operator takes two arguments that are both of the same interval type

Specified by:

getArgumentTypeNames in interface OperatorImplementation_V0104

Returns:

The names of the argument types

getIdentityElement

public ValueBuffer getIdentityElement()
                               throws NoIdentityElementException

The identity element of any interval intersect operator exists only if the base type underlying the interval type to which the intersect operator is applied, has a FIRST...() operator. If this is the case, then the identity element for the interval interesect operator is the interval that has the return value of said FIRST...() operator as its BEGIN component, and that stretches to infinity (i.e. has no END component, and thus includes all point values).

Specified by:

getIdentityElement in interface AggregationOperatorImplementation

Returns:

The identity element.

Throws:

NoIdentityElementException - If the conditions for an identity value to exist for this operator are not met

getReturnTypeDeclaration

public TypeDeclaration getReturnTypeDeclaration()

Description copied from interface: OperatorImplementation_V0105

Gets the full type declaration of the type of the return value. Differs from the _V0104 getReturnTypeName() in that for nonscalar return types, this method also returns the heading, not just only the RELATION or TUPLE typename.

Specified by:

getReturnTypeDeclaration in interface OperatorImplementation_V0105

Returns:

the full type declaration of the type of the return value

getReturnTypeName

public java.lang.String getReturnTypeName()

The return type of any interval intersect operator is the same as its argument types.

Specified by:

getReturnTypeName in interface OperatorImplementation_V0104

Returns:

the name of the type of the return value

getSignature

public java.lang.String getSignature()

Description copied from interface: OperatorImplementation_V0104

Gets the name of the operator implemented by this implementation object

Specified by:

getSignature in interface OperatorImplementation_V0104

Returns:

the name of the operator implemented by this implementation object

isDeterministic

public boolean isDeterministic()

Description copied from interface: OperatorImplementation_V0104

Tells whether the operator is deterministic with respect to the arguments of its invocations. An operator is deterministic if and only if for any two distinct invocations, if all the argument values are the same, then the result value returned will also be the same. An example of a nondeterministic operators is RANDOM().

Specified by:

isDeterministic in interface OperatorImplementation_V0104

Returns:

true if the operator is deterministic.

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException

Specified by:

readExternal in interface java.io.Externalizable

Throws:

java.io.IOException

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Specified by:

writeExternal in interface java.io.Externalizable

Throws:

java.io.IOException