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HermiT is reasoner for ontologies written using the Web Ontology Language (OWL). Given an OWL file, HermiT can determine whether or not the ontology is consistent, identify subsumption relationships between classes, and much more. This is the maven build of HermiT and is designed for people who wish to use HermiT from within the OWL API. It is now versioned in the main HermiT version repository, although not officially supported by the HermiT developers. The version number of this package is a composite of the HermiT version and an value representing releases of this packaged version. So, 1.3.7.1 is the first release of the mavenized version of HermiT based on the 1.3.7 release of HermiT. This package includes the Jautomata library (http://jautomata.sourceforge.net/), and builds with it directly. This library appears to be no longer under active development, and so a "fork" seems appropriate. No development is intended or anticipated on this code base.

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package rationals.converters.analyzers;

import rationals.Automaton;
import rationals.converters.ConverterException;
import rationals.transformations.Concatenation;
import rationals.transformations.Mix;
import rationals.transformations.Reducer;
import rationals.transformations.Shuffle;
import rationals.transformations.Star;
import rationals.transformations.Union;
// Grammar :
// E -> T E'
// E' -> + T E' | '/' '{' L '}' | eps
// T -> S T"
// T" -> '|' S T" | '#' S T" | eps
// S -> F T'
// T' -> F T' | eps
// F -> B B'
// B' -> * | int | ^ | eps
// B -> letter | 1 | 0 | ( E )
public class Parser {
    
  private Lexer lexico ;
  
  /**
   * Parse given string using standard grammar and lexical analyzer.
   * 
   * @param expression the expression to parse
   * @see Lexer
   * @see DefaultLexer
   */
  public Parser(String expression) {
    lexico = new DefaultLexer(expression) ;
  }

  /**
   * Parse using the given lexer. 
   * 
   * @param lexer the lexer to use for parsing.
   */
  public Parser(Lexer lexer) {
      this.lexico = lexer;
  }
  
  private Automaton error(String message) throws ConverterException {
    if (true) throw new ConverterException(
      "line " + lexico.lineNumber() + " , " + lexico.label() + " : " + message) ;
    return new Automaton() ;
  }
  
  public Automaton analyze() throws ConverterException {
    lexico.read() ;
    Automaton r = E() ;
    if (lexico.current() != Lexer.END) error("end of expression expected") ;
    return r ; 
  }
  
  private Automaton E() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL : {
        Automaton a = T() ;
        Automaton b = EP() ;
        return new Reducer().transform(new Union().transform(a , b)) ;
      }       
      case Lexer.CLOSE :
      case Lexer.END :
      case Lexer.UNION :
      case Lexer.SHUFFLE :
	  case Lexer.MIX : 
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("expression expected") ;
    }
  }

  private Automaton EP() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL : return error("union expected") ; 
      case Lexer.CLOSE :
      case Lexer.END : return new Automaton() ;
      case Lexer.UNION : {
        lexico.read() ;
        Automaton a = T() ;
        Automaton b = EP() ;
        return new Reducer().transform(new Union().transform(a , b)) ;
      }
      case Lexer.SHUFFLE :
	  case Lexer.MIX : 
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("union expected") ; 
    }
  }

  private Automaton T() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL : {
        Automaton a = S() ;
        Automaton b = TS() ;
        return new Reducer().transform(
          new Shuffle().transform(a , b)) ;
      }       
      case Lexer.CLOSE :
      case Lexer.END :
      case Lexer.UNION :
      case Lexer.SHUFFLE :
	  case Lexer.MIX : 
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("expression expected") ;
    }
  }

  private Automaton TS() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL :return error("concatenation expected") ;
      case Lexer.CLOSE :
      case Lexer.END : 
      case Lexer.UNION : return Automaton.epsilonAutomaton() ;
	  case Lexer.SHUFFLE : {
		lexico.read() ;
		Automaton a = S() ;
		Automaton b = TS() ;
		return new Reducer().transform(
		  new Shuffle().transform(a , b)) ;
	  }
	  case Lexer.MIX : 
	  	{
		lexico.read() ;
		Automaton a = S() ;
		Automaton b = TS() ;
		return new Reducer().transform(
		  new Mix().transform(a , b)) ;
	  }
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("concatenation expected") ; 
    }
  }

  private Automaton S() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL : {
        Automaton a = F() ;
        Automaton b = TP() ;
        return new Reducer().transform(
          new Concatenation().transform(a , b)) ;
      }       
      case Lexer.CLOSE :
      case Lexer.END :
      case Lexer.UNION :
      case Lexer.SHUFFLE :
	  case Lexer.MIX : 
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("expression expected") ;
    }
  }

  private Automaton TP() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL :{
        Automaton a = F() ;
        Automaton b = TP() ;
        return new Reducer().transform(
          new Concatenation().transform(a , b)) ;
      }
      case Lexer.CLOSE :
      case Lexer.END : 
      case Lexer.UNION : 
	  case Lexer.MIX : 
      case Lexer.SHUFFLE :return Automaton.epsilonAutomaton() ;
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("concatenation expected") ; 
    }
  }

  private Automaton F() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.OPEN :
      case Lexer.LABEL : {
        Automaton a = BP(B()) ; 
        return a ;
      }       
      case Lexer.CLOSE :
      case Lexer.END :
      case Lexer.UNION :
	  case Lexer.MIX : 
      case Lexer.SHUFFLE :
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("factor expected") ;
    }
  }

  private Automaton B() throws ConverterException {
    switch(lexico.current()) {
      case Lexer.EPSILON : {
        Automaton a = Automaton.epsilonAutomaton() ;
        lexico.read() ;
        return a ;
      }
      case Lexer.EMPTY : {
        Automaton a = new Automaton() ;
        lexico.read() ;
        return a ;
      }
      case Lexer.OPEN : {
        lexico.read() ;
        Automaton a = E() ;
        if (lexico.current() != Lexer.CLOSE) return error("( expected") ;
        lexico.read() ;
        return a ;
      }
      case Lexer.LABEL : {
        Automaton a = Automaton.labelAutomaton(lexico.label()) ;
        lexico.read() ;
        return a ;
      }      
      case Lexer.CLOSE :
      case Lexer.END :
      case Lexer.SHUFFLE :
	  case Lexer.MIX : 
      case Lexer.UNION :
      case Lexer.STAR :
      case Lexer.ITERATION :
      case Lexer.INT :
      default : return error("factor expected") ;
    }
  }

  private Automaton BP(Automaton a) throws ConverterException {
    switch(lexico.current()) {
      case Lexer.OPEN :
      case Lexer.LABEL :
      case Lexer.CLOSE :
      case Lexer.END :
      case Lexer.UNION : 
	  case Lexer.MIX : 
      case Lexer.SHUFFLE :return a ;
      case Lexer.STAR : {
        lexico.read() ; 
        return new Reducer().transform(new Star().transform(a)) ;
      }
      case Lexer.ITERATION :
        lexico.read() ; 
        return new Reducer().transform(
          new Concatenation().transform(a , 
            new Star().transform(a))) ;
      case Lexer.EPSILON :
      case Lexer.EMPTY :
      case Lexer.INT : {
        int value = lexico.value() ;
        lexico.read() ;
        Automaton b = Automaton.epsilonAutomaton() ;
        for (int i = 0 ; i < value ; i++) {
          b = new Reducer().transform(
            new Concatenation().transform(b , a)) ;
        }
        return b ;
      }
      default : return error("Unexpected character") ;
    }
  }
}