Package org.nineml.coffeegrinder.gll

Class GllParser

java.lang.Object

org.nineml.coffeegrinder.gll.GllParser

All Implemented Interfaces:

GearleyParser

public class GllParser
extends java.lang.Object
implements GearleyParser

The GLL parser.

The GLL parser compares an input sequence against a grammar and determines if the input is a sentence in the grammar.

This is an attempt to implement the work described in Derivation representation using binary subtree sets by Elizabeth Scott, Adrian Johnstone, and L. Thomas van Binsbergen. It returns the SPPF style forest derived from the binary subtrees. (There's some aspect of the description of how to extract trees directly from the BSR that I cannot grok.)

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	gllexecution	The logging category for the log messages about the execution of the GLL parser.
ParserGrammar	grammar	The grammar.
static java.lang.String	logcategory	The logging category for log messages about the GLL parser.

Constructor Summary

Constructors

Constructor	Description
GllParser(ParserGrammar grammar, ParserOptions options)	Construct a GLL parser.

Method Summary

Modifier and Type	Method	Description
int	getColumnNumber()	Returns the column number of the last character on the last line read by the parser.
int	getDefaultPriority()	The default priority.
ParserGrammar	getGrammar()	The grammar used by this parser.
int	getLineNumber()	Returns the line number of the last line read by the parser.
int	getOffset()	Returns the last offset read by the parser.
ParserType	getParserType()	The parser type.
java.lang.String	getPriorityStyle()	The priority style.
NonterminalSymbol	getSeed()	The seed used by this parser.
Token[]	getTokens()	Return the tokens used in the parse.
boolean	hasMoreInput()	Returns true of the parse ended without consuming all input.
GllResult	parse(java.lang.String input)	Parse a string.
GllResult	parse(java.util.Iterator<Token> input)	Parse a sequence of tokens provided by an iterator.
GllResult	parse(Token[] input)	Parse an array of tokens.
boolean	succeeded()	Did the parse succeed?

Methods inherited from class java.lang.Object

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

Field Detail

logcategory

public static final java.lang.String logcategory

The logging category for log messages about the GLL parser.

See Also:

Constant Field Values

gllexecution

public static final java.lang.String gllexecution

The logging category for the log messages about the execution of the GLL parser.

See Also:

Constant Field Values

grammar

public final ParserGrammar grammar

The grammar.

Constructor Detail

GllParser

public GllParser(ParserGrammar grammar,
                 ParserOptions options)

Construct a GLL parser.

Parameters:

grammar - the grammar.

options - the options.

Method Detail

parse

public GllResult parse(Token[] input)

Description copied from interface: GearleyParser

Parse an array of tokens.

Note that the GLL parser only parses character tokens.

Specified by:

parse in interface GearleyParser

Parameters:

input - The array of tokens.

Returns:

The parse result.

parse

public GllResult parse(java.util.Iterator<Token> input)

Description copied from interface: GearleyParser

Parse a sequence of tokens provided by an iterator.

Note that the GLL parser only parses character tokens.

Specified by:

parse in interface GearleyParser

Parameters:

input - The token iterator.

Returns:

The parse result.

parse

public GllResult parse(java.lang.String input)

Description copied from interface: GearleyParser

Parse a string.

Specified by:

parse in interface GearleyParser

Parameters:

input - The input string.

Returns:

The parse result.

succeeded

public boolean succeeded()

Did the parse succeed?

Is the parse finished and did it find at least one parse?

Returns:

true if it did.

getTokens

public Token[] getTokens()

Return the tokens used in the parse.

Returns:

the tokens.

getParserType

public ParserType getParserType()

Description copied from interface: GearleyParser

The parser type.

Specified by:

getParserType in interface GearleyParser

Returns:

The parser type.

getPriorityStyle

public java.lang.String getPriorityStyle()

Description copied from interface: GearleyParser

The priority style.

Meaningless if priorities are not used in the grammar.

Specified by:

getPriorityStyle in interface GearleyParser

Returns:

The priority style.

getDefaultPriority

public int getDefaultPriority()

Description copied from interface: GearleyParser

The default priority.

Meaningless if priorities are not used in the grammar.

Specified by:

getDefaultPriority in interface GearleyParser

Returns:

The default priority.

getGrammar

public ParserGrammar getGrammar()

Description copied from interface: GearleyParser

The grammar used by this parser.

Specified by:

getGrammar in interface GearleyParser

Returns:

The grammar.

getSeed

public NonterminalSymbol getSeed()

Description copied from interface: GearleyParser

The seed used by this parser.

Specified by:

getSeed in interface GearleyParser

Returns:

The seed token for this parse.

hasMoreInput

public boolean hasMoreInput()

Description copied from interface: GearleyParser

Returns true of the parse ended without consuming all input.

Specified by:

hasMoreInput in interface GearleyParser

Returns:

true if there was more input.

getOffset

public int getOffset()

Description copied from interface: GearleyParser

Returns the last offset read by the parser.

Specified by:

getOffset in interface GearleyParser

Returns:

the offset.

getLineNumber

public int getLineNumber()

Description copied from interface: GearleyParser

Returns the line number of the last line read by the parser.

Specified by:

getLineNumber in interface GearleyParser

Returns:

the line number.

getColumnNumber

public int getColumnNumber()

Description copied from interface: GearleyParser

Returns the column number of the last character on the last line read by the parser.

Specified by:

getColumnNumber in interface GearleyParser

Returns:

the column number.