net.percederberg.grammatica.parser
Class Parser

java.lang.Object
  net.percederberg.grammatica.parser.Parser

Direct Known Subclasses:

RecursiveDescentParser

public abstract class Parser

extends java.lang.Object

A base parser class. This class provides the standard parser interface, as well as token handling.

Method Summary

void	addPattern(ProductionPattern pattern) Adds a new production pattern to the parser.
Analyzer	getAnalyzer() Returns the analyzer in use by this parser.
Tokenizer	getTokenizer() Returns the tokenizer in use by this parser.
Node	parse() Parses the token stream and returns a parse tree.
protected abstract Node	parseStart() Parses the token stream and returns a parse tree.
void	prepare() Initializes the parser.
java.lang.String	toString() Returns a string representation of this parser.

Methods inherited from class java.lang.Object

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

Method Detail

getTokenizer

public Tokenizer getTokenizer()

Returns the tokenizer in use by this parser.

Returns:

the tokenizer in use by this parser

Since:

1.4

getAnalyzer

public Analyzer getAnalyzer()

Returns the analyzer in use by this parser.

Returns:

the analyzer in use by this parser

Since:

1.4

addPattern

public void addPattern(ProductionPattern pattern)
                throws ParserCreationException

Adds a new production pattern to the parser. The first pattern added is assumed to be the starting point in the grammar. The patterns added may be validated to some extent.

Parameters:

pattern - the pattern to add

Throws:

ParserCreationException - if the pattern couldn't be added correctly to the parser

prepare

public void prepare()
             throws ParserCreationException

Initializes the parser. All the added production patterns will be analyzed for ambiguities and errors. This method also initializes internal data structures used during the parsing.

Throws:

ParserCreationException - if the parser couldn't be initialized correctly

parse

public Node parse()
           throws ParserCreationException,
                  ParserLogException

Parses the token stream and returns a parse tree. This method will call prepare() if not previously called. In case of a parse error, the parser will attempt to recover and throw all the errors found in a parser log exception in the end.

Returns:

the parse tree

Throws:

ParserCreationException - if the parser couldn't be initialized correctly

ParserLogException - if the input couldn't be parsed correctly

See Also:

prepare()

parseStart

protected abstract Node parseStart()
                            throws ParseException

Parses the token stream and returns a parse tree.

Returns:

the parse tree

Throws:

ParseException - if the input couldn't be parsed correctly

toString

public java.lang.String toString()

Returns a string representation of this parser. The string will contain all the production definitions and various additional information.

Returns:

a detailed string representation of this parser