be.SIRAPRISE.typeimplementations

Class XMINUS_RELATION_RELATION

java.lang.Object

be.SIRAPRISE.typeimplementations.XMINUS_RELATION_RELATION

All Implemented Interfaces:

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

public final class XMINUS_RELATION_RELATION
extends java.lang.Object
implements AggregationOperatorImplementation

The relation XMINUS operator takes two arguments, both of a relation type. Both relation types must be the same.
An invocation of this XMINUS operator is equivalent to an invocation of XMINUSUSING_RELATION_RELATION, where the third argument mentions all the interval-typed attributes of the RELATION arguments' headings, in lexicographical order. Hence, per the definition of the three-argument version of XMINUS, an invocation XMINUS(r1,r2) is equivalent to UNION(MINUS(r1,r2,i),MINUS(r2,r1,i),i), where i are all the interval-typed attributes, in lexicographical order, of the heading of r1/r2.

Author:

Erwin

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
XMINUS_RELATION_RELATION(Heading heading) Creates the XMINUS_RELATION_RELATION

Method Summary

Modifier and Type	Method and Description
static java.util.Set<TupleBuffer>	computePlainSymmetricDifference(java.util.Set<TupleBuffer> r1, java.util.Set<TupleBuffer> r2) Computes the "plain" symmetric difference between the given two tuple sets.
ValueBuffer	executeOperator(java.util.LinkedList<ValueBuffer> args) Performs the actual logic of the operator.
java.lang.String[]	getArgumentTypeNames() Gets the list of names of types of the needed argument values
ValueBuffer	getIdentityElement() Gets the identity element of the operator in its domain.
TypeDeclaration	getReturnTypeDeclaration() Gets the full type declaration of the type of the return value.
java.lang.String	getReturnTypeName() Gets the name of the type of the return value
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

XMINUS_RELATION_RELATION

public XMINUS_RELATION_RELATION(Heading heading)

Creates the XMINUS_RELATION_RELATION

Parameters:

heading - The heading of the arguments to XMINUS

Method Detail

computePlainSymmetricDifference

public static java.util.Set<TupleBuffer> computePlainSymmetricDifference(java.util.Set<TupleBuffer> r1,
                                                                         java.util.Set<TupleBuffer> r2)

Computes the "plain" symmetric difference between the given two tuple sets. The "plain" symmetric difference contains all the tuples that appear in exactly one of the two argument relations.

Parameters:

r1 - The first argument

r2 - the second argument

Returns:

the "plain" symmetric difference between the given two tuple sets.

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()

Description copied from interface: OperatorImplementation_V0104

Gets the list of names of types of the needed argument values

Specified by:

getArgumentTypeNames in interface OperatorImplementation_V0104

Returns:

The names of the argument types

getIdentityElement

public ValueBuffer getIdentityElement()

Description copied from interface: AggregationOperatorImplementation

Gets the identity element of the operator in its domain.

Specified by:

getIdentityElement in interface AggregationOperatorImplementation

Returns:

The identity element.

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()

Description copied from interface: OperatorImplementation_V0104

Gets the name of the type of the return value

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)

Specified by:

readExternal in interface java.io.Externalizable

writeExternal

public void writeExternal(java.io.ObjectOutput out)

Specified by:

writeExternal in interface java.io.Externalizable