Package com.singularsys.extensions.structure

Class JavaIfRule

java.lang.Object

com.singularsys.extensions.structure.JavaIfRule

All Implemented Interfaces:

GrammaticalRuleI, GrammarMatcher, java.io.Serializable

public class JavaIfRule
extends java.lang.Object
implements GrammaticalRuleI

Parse a java style if statement: if(expr) statement [ else statement ]

 <JavaInRule> ::=
   || <if> <open> <expression> <close> <statement>
   || <if> <open> <expression> <close> <statement> <else> <statement> 
 

Author:

Richard Morris

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
JavaIfRule(SymbolToken ifToken, SymbolToken open, GrammaticalRuleI expression, SymbolToken close, GrammaticalRuleI statement, SymbolToken elseToken)

Method Summary

Modifier and Type	Method	Description
void	init(Jep jep)	Delayed initialisation, this methods is called whenever components of the jep instance are changed.
Node	match(Lookahead2Iterator<Token> it, GrammarParser parser)	Attempt to parse the input using the rule

Methods inherited from class java.lang.Object

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

Constructor Detail

JavaIfRule

public JavaIfRule(SymbolToken ifToken,
                  SymbolToken open,
                  GrammaticalRuleI expression,
                  SymbolToken close,
                  GrammaticalRuleI statement,
                  SymbolToken elseToken)

Parameters:

ifToken - token representing "if"

open - opening bracket

expression - rule for parsing expressions

close - closing bracket

statement - rule for parsing statements

elseToken - token representing "else"

Method Detail

init

public void init(Jep jep)

Description copied from interface: GrammarMatcher

Delayed initialisation, this methods is called whenever components of the jep instance are changed.

Specified by:

init in interface GrammarMatcher

Parameters:

jep - the current jep instance.

match

public Node match(Lookahead2Iterator<Token> it,
                  GrammarParser parser)
           throws ParseException

Description copied from interface: GrammaticalRuleI

Attempt to parse the input using the rule

Specified by:

match in interface GrammarMatcher

Specified by:

match in interface GrammaticalRuleI

Parameters:

it - iterator with tokens to parse

parser - the parser to parse any components of the rule

Returns:

successful parses should return a Node, null if unsuccessful

Throws:

ParseException - if there is a syntactical error