package graph;import java.awt.*;import java.applet.*;import java.util.*;import java.lang.*;/*****************************************************************************    Class  ScanString******************************************************************************    Copyright (C) 1996 Leigh Brookshaw****    This program is free software; you can redistribute it and/or modify**    it under the terms of the GNU General Public License as published by**    the Free Software Foundation; either version 2 of the License, or**    (at your option) any later version.****    This program is distributed in the hope that it will be useful,**    but WITHOUT ANY WARRANTY; without even the implied warranty of**    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the**    GNU General Public License for more details.****    You should have received a copy of the GNU General Public License**    along with this program; if not, write to the Free Software**    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.**************************************************************************//** * This class is similar to the ScanWord class, except it scans a string * for keywords rather than an input stream. * * @version $Revision: 1.5 $, $Date: 1996/07/12 00:35:49 $ * @author Leigh Brookshaw */ public class ScanString extends Object {/************************ Constants********************/  /**   * flag an unknown token   */     public final static int UNKNOWN = -256;  /**   * Flag an error   */     public final static int ERROR   = -257;  /**   * Flag a Number   */     public final static int NUMBER  = -258;  /**   * flag the End of String   */     public final static int EOS     = -259;     /************************* Private Variables********************/     private String string;          private char buffer[];          private int count;     private int position;     private int kwlength;          public String sval;     public double nval;     /***   The hash table containing the keyword/value pairs.*/          private Hashtable kwords = new Hashtable();/*********************** Constructors*******************/  /**   * Instantiate the Class   */     public ScanString( ) {         string = null;         count = 0;         position = 0;         kwlength = 0;         buffer = new char[32];         sval = null;         nval = 0.0;     }  /**   * Instantaite the Class   * @param s String to scan for tokens   */     public ScanString( String s ) {         setString(s);     }     /*************************  Public Methods*********************/  /**   * Set the string to be scanned   * @param s String   */    public void setString( String s ) {         if(s == null) return;         string = new String(s);         //System.out.println("ScanSring: string="+string);     }           /**   *  Add a keyword/token pair to the table of keywords to scan for.   * @param s keyword string to scan for   * @param i token to return when the keyword is found   */     public void addKeyWord ( String s, int i) {          if(s == null) return;          if( kwlength < s.length() ) kwlength = s.length();          kwords.put(s.toLowerCase(), new Integer(i));          //System.out.println("addKeyWord: key="+s.toLowerCase()+" value="+i);	}  /**   * @param s keyword string   * @return the token corresponding to the keyword   */     public int getKeyValue (String s) {          if(s == null) return UNKNOWN;          if( !kwords.containsKey(s.toLowerCase())) return UNKNOWN;          Integer i = (Integer)kwords.get(s.toLowerCase());          if(i == null) return UNKNOWN;          else          return i.intValue();	}  /**   *   Clear the table containing the keyword/token pairs   */     public void resetKeyWords () {          kwords.clear();          kwlength = 0;	}  /**   *  Process the string and return the next token found.   * @return token found   */     public int nextWord() {        int i;     	char c;        int word;        int count = 0;        char buffer[] = new char[string.length()];        boolean exponent = false;        boolean point = false;        if(position >= string.length() ) return EOS;        c = string.charAt(position);/***      Remove white space*/        while( c == 32 || c == 9 || c == 10 || c == 11 || c == 13 ) {                position++;                if( position >= string.length() ) return EOS;                c = string.charAt(position);	}/***      Is this the start of a number ?*/        if( (c >= '0' && c <= '9') || c == '.' ) {               //System.out.println("ScanString: Scan for number!");               for(i=position; i<string.length(); i++) {                   c = string.charAt(i);                   if(exponent && ( c < '0' || c > '9' ) ) break;                   if( c == 'E' || c =='e' ||                       c == 'D' || c =='d' ) {                             exponent = true;                             buffer[count++] = 'e';                             c = string.charAt(i+1);                             if(  c == '-' || c == '+' ) {                                     buffer[count++] = c;                                     i++;                             }                   } else                   if( point && c == '.' ) {                                   break;                   } else	           if( c == '.' ) {                                   point = true;                                   buffer[count++] = c;                    } else                   if(  c < '0' || c > '9' ) {                                  break;                   } else {                                  buffer[count++] = c;                   }	       }               try {               sval = new String(buffer,0,count);               nval = Double.valueOf(sval).doubleValue();               position += count;               return NUMBER;	       }               catch (Exception e) {               return ERROR;	       }        } else {/***      Scan for a keyword*/         //System.out.println("ScanString: Scan for Word!");         //System.out.println("ScanString: Maximum Keyword length "+kwlength);           int last = UNKNOWN;           int nchar = 0;           int pos = position;                      while (pos < string.length() )  {        	buffer[count++] = string.charAt(pos++);                word = getKeyValue(new String(buffer,0,count));                if(word != UNKNOWN ) {                      last = word;                      nchar = count;                    //System.out.println("ScanString: Found KeyWord - "+                    //       new String(buffer,0,count));                } else	        if( nchar == 0 && count >= kwlength ) {                      return ERROR;                } else                if( count >= kwlength ) {                       sval = new String(buffer,0,nchar);                       position += nchar;                     //System.out.println("ScanString: Returning KeyWord - "+                     //         sval);                       return last;	        }           }           if( nchar != 0 ) {               sval = new String(buffer,0,nchar);               position += nchar;             //System.out.println("ScanString: Returning KeyWord - "+             //                 sval);               return last;	   }	}            return ERROR;                             }             }