net.oneandone.mork.grammar

Class Grammar

java.lang.Object

net.oneandone.mork.grammar.GrammarBase

net.oneandone.mork.grammar.Grammar

public class Grammar
extends GrammarBase

Context free grammar. Symbols are coded as ints. Preferred variable name for symbols is sym. Productions are coded as ints. Preferred variable name for productions is prod.

Nested Class Summary

Nested classes/interfaces inherited from class net.oneandone.mork.grammar.GrammarBase

GrammarBase.PreSymbol

Field Summary

Fields

Modifier and Type	Field and Description
static String	NOT_PRODUCTIVE
static String	NOT_REACHABLE

Constructor Summary

Constructors

Constructor and Description
Grammar()
Grammar(int start)
Grammar(int start, StringArrayList symbolTable)

Method Summary

Modifier and Type	Method and Description
void	addNullable(net.oneandone.sushi.util.IntBitSet result) Returns a symbols that can derive the empty word.
void	addProductions(Grammar right)
void	addReachable(int sym, net.oneandone.sushi.util.IntBitSet result, net.oneandone.sushi.util.IntBitSet recurse)
void	addTerminable(net.oneandone.sushi.util.IntBitSet result)
void	check(int startSym, net.oneandone.sushi.util.IntBitSet usedSymbols, List<String> symbolTable)
void	expandSymbol(int symbol) expansion is not performed recurively
Map<Integer,PrefixSet>	firsts(int k)
static Grammar	forProductions(String... prods)
int	getAlternative(int sym, int no)
int	getAlternativeCount(int sym)
int	getLeft(int prod)
int	getLength(int prod)
void	getNonterminals(net.oneandone.sushi.util.IntBitSet result)
int	getRight(int prod, int ofs)
int	getStart()
int	getSymbol(int prod, int ofs)
int	getSymbolCount() Every index less than getSymbolCount() is a valid symbol -- it's considered an unused terminal if does not occur in any production.
void	getSymbols(net.oneandone.sushi.util.IntBitSet result)
StringArrayList	getSymbolTable()
void	getTerminals(net.oneandone.sushi.util.IntBitSet result)
void	getUsedTerminals(net.oneandone.sushi.util.IntBitSet result)
int	getUser(int sym, int no)
int	getUserCount(int sym)
int	getUserOfs(int sym, int no, int idx)
int	getUserOfsCount(int sym, int no)
boolean	isNonterminal(int sym)
boolean	isTerminal(int sym)
boolean	isUsedTerminal(int sym)
void	packSymbols(int first, int end) pack helper symbols
String	prodToString(int prod)
void	prodToString(StringBuilder buffer, int prod)
void	removeDuplicateRules()
void	removeDuplicateSymbols(int first, int last)
void	removeProductions(int symbol)
boolean	renameSymbol(int prev, int next)
String	toString()

Methods inherited from class net.oneandone.mork.grammar.GrammarBase

addProduction, addProduction, getProduction, getProductionCount, getSymbol, getSymbols, removeProduction

Methods inherited from class java.lang.Object

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

Field Detail

NOT_PRODUCTIVE

public static final String NOT_PRODUCTIVE

See Also:

Constant Field Values

NOT_REACHABLE

public static final String NOT_REACHABLE

See Also:

Constant Field Values

Constructor Detail

Grammar

public Grammar()

Grammar

public Grammar(int start)

Grammar

public Grammar(int start,
               StringArrayList symbolTable)

Method Detail

forProductions

public static Grammar forProductions(String... prods)

check

public void check(int startSym,
                  net.oneandone.sushi.util.IntBitSet usedSymbols,
                  List<String> symbolTable)
           throws GenericException

Parameters:

usedSymbols - are always considered reachable

Throws:

GenericException

getStart

public int getStart()

getSymbolTable

public StringArrayList getSymbolTable()

getLength

public int getLength(int prod)

Returns:

number of symbols on right-hand-side

getSymbol

public int getSymbol(int prod,
                     int ofs)

getLeft

public int getLeft(int prod)

getRight

public int getRight(int prod,
                    int ofs)

getAlternativeCount

public int getAlternativeCount(int sym)

getAlternative

public int getAlternative(int sym,
                          int no)

Returns:

a production

getUserCount

public int getUserCount(int sym)

getUser

public int getUser(int sym,
                   int no)

Returns:

a production

getUserOfsCount

public int getUserOfsCount(int sym,
                           int no)

getUserOfs

public int getUserOfs(int sym,
                      int no,
                      int idx)

getSymbolCount

public int getSymbolCount()

Every index less than getSymbolCount() is a valid symbol -- it's considered an unused terminal if does not occur in any production.

getTerminals

public void getTerminals(net.oneandone.sushi.util.IntBitSet result)

getUsedTerminals

public void getUsedTerminals(net.oneandone.sushi.util.IntBitSet result)

getNonterminals

public void getNonterminals(net.oneandone.sushi.util.IntBitSet result)

getSymbols

public void getSymbols(net.oneandone.sushi.util.IntBitSet result)

isTerminal

public boolean isTerminal(int sym)

isUsedTerminal

public boolean isUsedTerminal(int sym)

isNonterminal

public boolean isNonterminal(int sym)

addTerminable

public void addTerminable(net.oneandone.sushi.util.IntBitSet result)

Parameters:

result - normally the set of terminals.

addReachable

public void addReachable(int sym,
                         net.oneandone.sushi.util.IntBitSet result,
                         net.oneandone.sushi.util.IntBitSet recurse)

Parameters:

result - out-argument: symbols already reached - recursion must stop there.

recurse - all symbols to recurse. null: all

firsts

public Map<Integer,PrefixSet> firsts(int k)

addProductions

public void addProductions(Grammar right)

removeDuplicateRules

public void removeDuplicateRules()

removeDuplicateSymbols

public void removeDuplicateSymbols(int first,
                                   int last)

packSymbols

public void packSymbols(int first,
                        int end)

pack helper symbols

Parameters:

end - = last + 1

renameSymbol

public boolean renameSymbol(int prev,
                            int next)

removeProductions

public void removeProductions(int symbol)

expandSymbol

public void expandSymbol(int symbol)

expansion is not performed recurively

addNullable

public void addNullable(net.oneandone.sushi.util.IntBitSet result)

Returns a symbols that can derive the empty word. Also called removable symbols

toString

public String toString()

Overrides:

toString in class Object

prodToString

public String prodToString(int prod)

prodToString

public void prodToString(StringBuilder buffer,
                         int prod)