Package net.sf.tweety.action.description.parser

Class CLawParser

java.lang.Object

net.sf.tweety.commons.Parser<CActionDescription,Formula>

net.sf.tweety.action.description.parser.CLawParser

public class CLawParser
extends Parser<CActionDescription,Formula>

This class implements a parser for causal laws in C. The BNF of such rules is given by: (starting symbol is DESC)

DESC ::== LAW ("\n" LAW)*
LAW ::== STATICLAW | DYNAMICLAW
STATICLAW ::== "caused" FOLFORMULA ("if" FOLFORMULA)? ("requires" REQUIREMENTS)?
DYNAMICLAW ::== "caused" FOLFORMULA ("if" FOLFORMULA)? "after" FOLFORMULA ("requires" REQUIREMENTS)?
REQUIREMENTS ::== REQUIREMENT ("," REQUIREMENT)*
REQUIREMENT ::== (VARIABLENAME "<>" VARIABLENAME | VARIABLENAME "<>" CONSTANTNAME)*
where FOLFORMULA is an unquantified first-order formula without functors,
and VARIABLENAME, CONSTANTNAME are sequences of symbols
from {a,...,z,A,...,Z,0,...,9} with a letter at the beginning.

Author:

Sebastian Homann

Field Summary

Fields

Modifier and Type	Field	Description
protected ActionSignature	signature

Constructor Summary

Constructors

Constructor	Description
CLawParser(ActionSignature signature)	This parser needs a valid action signature to parse causal laws.

Method Summary

Modifier and Type	Method	Description
protected java.util.Set<java.lang.String>	containedKeywords(java.lang.String s)	Returns the set of forbidden keywords, that are contained in a string.
private Formula	parseAlwaysFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form always A which is converted to caused - if !A
CActionDescription	parseBeliefBase(java.io.Reader reader)	Parses the given reader into a belief base of the given type.
private Formula	parseCausedFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form caused A (if B)? (after C)?
private Formula	parseCausesFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form A causes B if C which is converted to caused B if + after A && C
private Formula	parseDefaultFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form default A (if B)? which is converted to the causal law caused A if A && B
protected FolFormula	parseFolFormula(java.lang.String s)	Parses a FolFormula from a string using the FolParser class
Formula	parseFormula(java.io.Reader reader)	Parses the given reader into a formula of the given type.
Formula	parseFormula(java.lang.String s)	Parses the given text into a formula of the given type.
private Formula	parseInertialFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form inertial A which is converted to the causal law caused A if A after A
private Formula	parseMayCauseFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form A may cause B if C which is converted to caused B if B after A && C
private Formula	parseNonexecutableFormula(java.lang.String s, java.lang.String reqString)	Parses a string containing a single causal law of the form nonexecutable A if B which is converted to caused - after A && B

Methods inherited from class net.sf.tweety.commons.Parser

isNumeric, parseBeliefBase, parseBeliefBaseFromFile, parseFormulaFromFile

Methods inherited from class java.lang.Object

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

Field Detail

signature

protected ActionSignature signature

Constructor Detail

CLawParser

public CLawParser(ActionSignature signature)

This parser needs a valid action signature to parse causal laws.

Parameters:

signature - some signature

Method Detail

parseBeliefBase

public CActionDescription parseBeliefBase(java.io.Reader reader)
                                   throws ParserException

Description copied from class: Parser

Parses the given reader into a belief base of the given type.

Specified by:

parseBeliefBase in class Parser<CActionDescription,Formula>

Parameters:

reader - a reader

Returns:

a belief base

Throws:

ParserException - some parsing exceptions may be added here.

parseFormula

public Formula parseFormula(java.io.Reader reader)
                     throws java.io.IOException,
                            ParserException

Description copied from class: Parser

Parses the given reader into a formula of the given type.

Specified by:

parseFormula in class Parser<CActionDescription,Formula>

Parameters:

reader - a reader

Returns:

a formula

Throws:

java.io.IOException - if some IO issue occurred.

ParserException - some parsing exceptions may be added here.

parseFolFormula

protected FolFormula parseFolFormula(java.lang.String s)
                              throws ParserException,
                                     java.io.IOException

Parses a FolFormula from a string using the FolParser class

Parameters:

s - a string

Returns:

A first order formula

Throws:

ParserException - if parsing fails

java.io.IOException - if an IO issue occurs.

parseFormula

public Formula parseFormula(java.lang.String s)
                     throws ParserException,
                            java.io.IOException

Description copied from class: Parser

Parses the given text into a formula of the given type.

Overrides:

parseFormula in class Parser<CActionDescription,Formula>

Parameters:

s - a string

Returns:

a formula

Throws:

ParserException - some parsing exceptions may be added here.

java.io.IOException - if some IO issue occurred.

parseCausedFormula

private Formula parseCausedFormula(java.lang.String s,
                                   java.lang.String reqString)
                            throws ParserException,
                                   java.io.IOException

Parses a string containing a single causal law of the form caused A (if B)? (after C)?

Parameters:

s - a string containing a single causal law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

parseInertialFormula

private Formula parseInertialFormula(java.lang.String s,
                                     java.lang.String reqString)
                              throws ParserException,
                                     java.io.IOException

Parses a string containing a single causal law of the form inertial A which is converted to the causal law caused A if A after A

Parameters:

s - a string containing a single inertial law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

parseDefaultFormula

private Formula parseDefaultFormula(java.lang.String s,
                                    java.lang.String reqString)
                             throws ParserException,
                                    java.io.IOException

Parses a string containing a single causal law of the form default A (if B)? which is converted to the causal law caused A if A && B

Parameters:

s - a string containing a single causal law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

parseCausesFormula

private Formula parseCausesFormula(java.lang.String s,
                                   java.lang.String reqString)
                            throws ParserException,
                                   java.io.IOException

Parses a string containing a single causal law of the form A causes B if C which is converted to caused B if + after A && C

Parameters:

s - a string containing a single causal law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

parseAlwaysFormula

private Formula parseAlwaysFormula(java.lang.String s,
                                   java.lang.String reqString)
                            throws ParserException,
                                   java.io.IOException

Parses a string containing a single causal law of the form always A which is converted to caused - if !A

Parameters:

s - a string containing a single causal law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

parseNonexecutableFormula

private Formula parseNonexecutableFormula(java.lang.String s,
                                          java.lang.String reqString)
                                   throws ParserException,
                                          java.io.IOException

Parses a string containing a single causal law of the form nonexecutable A if B which is converted to caused - after A && B

Parameters:

s - a string containing a single causal law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

parseMayCauseFormula

private Formula parseMayCauseFormula(java.lang.String s,
                                     java.lang.String reqString)
                              throws ParserException,
                                     java.io.IOException

Parses a string containing a single causal law of the form A may cause B if C which is converted to caused B if B after A && C

Parameters:

s - a string containing a single causal law.

reqString - the grounding requirements of this law.

Returns:

the corresponding causal law

Throws:

ParserException - if parsing failes

java.io.IOException - if io failes

containedKeywords

protected java.util.Set<java.lang.String> containedKeywords(java.lang.String s)

Returns the set of forbidden keywords, that are contained in a string. This is used for error recognition in input strings.

Parameters:

s - some string

Returns:

the set of forbidden keywords