Class PhysicalOpMultiRequest

java.lang.Object

se.liu.ida.hefquin.engine.queryplan.physical.impl.PhysicalOpMultiRequest

All Implemented Interfaces:

QueryPlanOperator, NullaryPhysicalOp, NullaryPhysicalOpForLogicalOp, PhysicalOperator, PhysicalOperatorForLogicalOperator

public class PhysicalOpMultiRequest
extends Object
implements NullaryPhysicalOpForLogicalOp

A physical operator that is meant to be used for the logical operator LogicalOpMultiRequest. It performs requests with the same graph pattern at multiple federation members in parallel and, then, outputs the solution mappings obtained via all these requests, where each solution mapping is extended with a binding that captures the service variable with the service URI of the federation member from which it was obtained. The actual algorithm of this operator is implemented in the ExecOpMultiRequest class.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PhysicalOpMultiRequest.Factory

Field Summary

Fields

Modifier and Type	Field	Description
protected static final PhysicalOpMultiRequest.Factory	factory
protected final LogicalOpMultiRequest	lop

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PhysicalOpMultiRequest(LogicalOpMultiRequest lop)

Method Summary

Modifier and Type	Method	Description
NullaryExecutableOp	createExecOp(boolean collectExceptions, QueryPlanningInfo qpInfo, ExpectedVariables... inputVars)	Creates and returns the executable operator to be used for this physical operator.
boolean	equals(Object o)
static PhysicalOpFactory	getFactory()
LogicalOpMultiRequest	getLogicalOperator()	Returns the logical operator implemented by this physical operator.
int	hashCode()
String	toString()
void	visit(PhysicalPlanVisitor visitor)

Methods inherited from class java.lang.Object

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

Methods inherited from interface se.liu.ida.hefquin.engine.queryplan.physical.PhysicalOperatorForLogicalOperator

getExpectedVariables

Field Details

factory

protected static final PhysicalOpMultiRequest.Factory factory

lop

protected final LogicalOpMultiRequest lop

Constructor Details

PhysicalOpMultiRequest

protected PhysicalOpMultiRequest(LogicalOpMultiRequest lop)

Method Details

getFactory

public static PhysicalOpFactory getFactory()

getLogicalOperator

public LogicalOpMultiRequest getLogicalOperator()

Description copied from interface: PhysicalOperatorForLogicalOperator

Returns the logical operator implemented by this physical operator.

Specified by:

getLogicalOperator in interface NullaryPhysicalOpForLogicalOp

Specified by:

getLogicalOperator in interface PhysicalOperatorForLogicalOperator

createExecOp

public NullaryExecutableOp createExecOp(boolean collectExceptions,
 QueryPlanningInfo qpInfo,
 ExpectedVariables... inputVars)

Description copied from interface: PhysicalOperator

Creates and returns the executable operator to be used for this physical operator. The implementation of this method has to create a new ExecutableOperator object each time it is called. The given QueryPlanningInfo object is passed to the created executable operator (to be available via the ExecutableOperator.getQueryPlanningInfo() method) and should be taken from the physical plan whose root operator is this physical operator. The given collectExceptions flag is passed to the executable operator and determines whether that operator collects its exceptions (see ExecutableOperator.getExceptionsCaughtDuringExecution()) or throws them immediately. The number of ExpectedVariables objects passed as arguments to this method must be in line with the degree of this operator (e.g., for a unary operator, exactly one such object must be passed).

Specified by:

createExecOp in interface NullaryPhysicalOp

Specified by:

createExecOp in interface PhysicalOperator

visit

public void visit(PhysicalPlanVisitor visitor)

Specified by:

visit in interface PhysicalOperator

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object