de.grogra.xl.query
Interface Producer

All Known Implementing Classes:

DOMProducer, Producer, RGGProducer, SimpleProducer, VVProducer

public interface Producer

A Producer is used within right hand sides of XL rules in order to construct the replacement for the match of the left hand side.

Author:

Ole Kniemeyer

Field Summary

static int	DOUBLE_ARROW Indicates the XL rule arrow ==>>.
static int	EXECUTION_ARROW Indicates the XL rule arrow ::>.
static int	SIMPLE_ARROW Indicates the XL rule arrow ==>.

Method Summary

boolean	producer$beginExecution(int arrow) This method is invoked by the XL run-time system in order to notify the producer about the beginning of a right-hand side (i.e., a match for the left-hand side has been found, and the right-hand side is executed).
void	producer$endExecution(boolean executed) This method is invoked by the XL run-time system in order to notify the producer about the end of the execution of a right-hand side.
Graph	producer$getGraph() Returns the graph for which this producer constructs the right-hand side structur.
void	producer$visitEdge(EdgePattern pattern)

Field Detail

DOUBLE_ARROW

static final int DOUBLE_ARROW

Indicates the XL rule arrow ==>>.

See Also:

Constant Field Values

EXECUTION_ARROW

static final int EXECUTION_ARROW

Indicates the XL rule arrow ::>.

See Also:

Constant Field Values

SIMPLE_ARROW

static final int SIMPLE_ARROW

Indicates the XL rule arrow ==>.

See Also:

Constant Field Values

Method Detail

producer$beginExecution

boolean producer$beginExecution(int arrow)

This method is invoked by the XL run-time system in order to notify the producer about the beginning of a right-hand side (i.e., a match for the left-hand side has been found, and the right-hand side is executed).

Parameters:

arrow - the type of rule arrow, one of SIMPLE_ARROW, DOUBLE_ARROW, EXECUTION_ARROW

Returns:

true if the right-hand side shall be executed, false if its execution shall be skipped

producer$endExecution

void producer$endExecution(boolean executed)

This method is invoked by the XL run-time system in order to notify the producer about the end of the execution of a right-hand side.

Parameters:

executed - return value of invocation of producer$beginExecution(int)

producer$getGraph

Graph producer$getGraph()

Returns the graph for which this producer constructs the right-hand side structur.

Returns:

the graph on which this producer operates

producer$visitEdge

void producer$visitEdge(EdgePattern pattern)