com.hp.hpl.jena.sparql.engine.optimizer
Class StatsMatcher

java.lang.Object
  extended by com.hp.hpl.jena.sparql.engine.optimizer.StatsMatcher

public final class StatsMatcher
extends Object

Stats format:

(stats
    (meta ...)
    ((S P O) weight)
    ( weight)
  )
where S, P, O is a URI, variable, literal or one of the words ANY (matches anything), VAR (matches a variable), TERM (matches a fixed URI, or literal), URI, BNODE, LITERAL (matches one of these types).


Field Summary
static String COUNT
           
static String META
           
static Item OTHER
           
static String STATS
           
static double weightPO
           
static double weightPO_small
           
static double weightSP
           
static double weightSP_small
           
static double weightTypeO
           
static double weightTypeO_small
           
 
Constructor Summary
StatsMatcher()
           
StatsMatcher(Item stats)
           
StatsMatcher(String filename)
           
 
Method Summary
 void addPattern(Pattern pattern)
           
 void addPatterns(com.hp.hpl.jena.graph.Node predicate, double numProp)
          Add patterns based solely on the predicate count and some guessing
 void addPatternsSmall(com.hp.hpl.jena.graph.Node predicate, double numProp)
          Add patterns based solely on the predicate count and some guessing for a small graph (less than a few thousand triples)
 double match(Item subj, Item pred, Item obj)
          Return the matching weight for the first triple match found, else apply default value for fixed, unknnown predciate, else return NOMATCH
 double match(PatternTriple pTriple)
           
 double match(com.hp.hpl.jena.graph.Triple t)
           
 void printSSE(PrintStream ps)
           
 String toString()
           
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

STATS

public static final String STATS
See Also:
Constant Field Values

META

public static final String META
See Also:
Constant Field Values

COUNT

public static final String COUNT
See Also:
Constant Field Values

OTHER

public static final Item OTHER

weightSP

public static final double weightSP
See Also:
Constant Field Values

weightPO

public static final double weightPO
See Also:
Constant Field Values

weightTypeO

public static final double weightTypeO
See Also:
Constant Field Values

weightSP_small

public static final double weightSP_small
See Also:
Constant Field Values

weightPO_small

public static final double weightPO_small
See Also:
Constant Field Values

weightTypeO_small

public static final double weightTypeO_small
See Also:
Constant Field Values
Constructor Detail

StatsMatcher

public StatsMatcher()

StatsMatcher

public StatsMatcher(String filename)

StatsMatcher

public StatsMatcher(Item stats)
Method Detail

addPatterns

public void addPatterns(com.hp.hpl.jena.graph.Node predicate,
                        double numProp)
Add patterns based solely on the predicate count and some guessing


addPatternsSmall

public void addPatternsSmall(com.hp.hpl.jena.graph.Node predicate,
                             double numProp)
Add patterns based solely on the predicate count and some guessing for a small graph (less than a few thousand triples)


addPattern

public void addPattern(Pattern pattern)

match

public double match(com.hp.hpl.jena.graph.Triple t)

match

public double match(PatternTriple pTriple)

match

public double match(Item subj,
                    Item pred,
                    Item obj)
Return the matching weight for the first triple match found, else apply default value for fixed, unknnown predciate, else return NOMATCH


toString

public String toString()
Overrides:
toString in class Object

printSSE

public void printSSE(PrintStream ps)


Licenced under the Apache License, Version 2.0