tttest.java

一个简单有效的CMM语言的词法分析器,带图形界面

import java.io.*;
import java.util.*;
public class  TTTest
{
  public static void main(String[] args)
  {
   System.out.println("符号表文件会输出在一个叫table.dat的文件中");
   System.out.println("二元式文件会输出在一个叫TableTwoNUM.dat的文件中");
   System.out.println("错误文件会输出在一个叫wrongFile.dat的文件中");
   System.out.println("请输入要解析文件的名字");
   try{
    BufferedReader reader =
        new BufferedReader( new InputStreamReader(System.in) );
 
    String name = reader.readLine();
    Table myTable = new Table();
    TokenGet tokenGet= new TokenGet(name,myTable);
    
    tokenGet.putBuffer();
  
    String s;
    while(!TokenGet.endOfFenX)
    {
    s= tokenGet.nextToken();
    System.out.println( s );
    System.out.println("识别出一个表示符");
    }
    myTable.printTable();
    }catch(Exception e){e.printStackTrace();}
   }
}
    
  class  TokenGet
{
   public  TokenGet( String name ,Table aTable)
   {
      endOfFenX= false; 
      name = name.trim();
      table = aTable;
      try
      {
         wrongFile = new PrintWriter( new FileWriter("WrongFile.dat"));
         in = new BufferedReader( new FileReader( name ) );
      }
      catch(IOException e) { e.printStackTrace();}
   }
   String   nextToken()
   {
     String theid;
     isDouble=false;
     begining=ending;
     System.out.println("beginning="+begining);//
     System.out.println("ending="+ending);//
       char c;
     state=0; //at the begining 
     while(true)
     {
     System.out.println("beginning="+begining);
     System.out.println("ending="+ending);
       switch( state )
       {
        //识别空白t
         case -1:
            return "WWWWWW";
         case 0: 
            c=nextChar();
            if( c==' '||c=='\t'||c=='\n' )
            {
            state = 1;
            System.out.println("black1");
            }
            else 
            
            state=fail();
            
            
            break;
         case 1:
            c=nextChar();
            if( c==' '||c=='\t' )
            {        
           System.out.println("black2");
            state = 1;
            }
            else // text begining
            {
              state=2;
            }
              break;
         case 2:
             state = 3;
             ungetChar();
             
             break;
           //识别标识符 id
         case 3:
            c= nextChar();
            if( isLetter(c) )
            {
               state=4;
            }
            else state = fail();
            System.out.println("State 3");
            break;
          case 4:
            c= nextChar();
            if( isLetter(c) || isDigit(c) )
            {
              state=4;
            }
            else state=5;
            System.out.println("State 4");
            break;
          case 5:
            ungetChar();
            System.out.println("beginning="+begining);
            System.out.println("ending="+ending);
            theid=buffer.substring(begining,ending);
            table.insert( theid , theid.length() ,"","","");
            System.out.println("State 5");
            return "the id";
          //识别括号和;
          case 6:
            c=nextChar();
            if(c=='(') 
            {        
              state = 7;
               System.out.println("ok");
            }
            else if( (c==')') )  
              
              state=8;
            else if( (c=='{') )
              state=9;
            else if( (c=='}') )
              state=10;
            else if( (c==';') )
              state=11;
            else state=fail();
            System.out.println("State 6");
            break;
          case 7: 
            System.out.println("括号1");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
            return "(";
          case 8: 
            System.out.println("括号2");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
            return ")";
          case 9: 
            System.out.println("括号3");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
            return "{";
            case 10: 
            System.out.println("括号4");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
            return "}";
          case 11:
            System.out.println("括号5");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
            return ";";
          
          //识别NUMBER
          case 12:
            c=nextChar();
            if( isDigit(c) )
              state=13;
            else state=fail();
            System.out.println("state 12");
            break;
          case 13:
            c=nextChar();
            if( isDigit(c) )
              state=13;
 
            else if( (c=='.') )
            {
              isDouble=true;
              state=14;
            }
             
            else if(isLetter(c)) 
              {getWrong(); state=16;}
            else 
            state=16;
            System.out.println("state 13");           
            break;
          case 14:
            c=nextChar();
            if( isDigit(c) )
              state=15;
            else if( isLetter(c) )
              getWrong();
            System.out.println("state 14");
            break;
             
         case 15:
           c=nextChar();
           if( isDigit(c) )
              state=15;
           else if(isLetter(c))
           {
             getWrong();state=16;
           }
           else state= 16;
            System.out.println("state 15");
           break;
        case  16:
           ungetChar();
           theid=buffer.substring(begining,ending);
           if(isDouble())
           table.insert( "" , 1000 ,"实型","常数",theid);
           else    table.insert( "" , 1000 ,"整型","常数",theid);
           System.out.println("State 5");
           return "number";
          //识别STRING
        case 17:
           c=nextChar();
           if((c=='\"'))
            state=18;
           else state=fail();
           System.out.println("state 17");
           break;
        case 18:
           c=nextChar();
           if(isLetter(c))
             state=19;
           System.out.println("state 18");
           break;
        case 19:
           c=nextChar();
           if(isLetter(c))
             state=19;
           else if((c=='\"'))
             state=20;
           System.out.println("state 19");
           break;
       case 20:
           theid=buffer.substring(begining,ending);
           table.insert( theid , theid.length()-2 ,"字符串型","常数","");
           System.out.println("state 20");
           return "String";
       //识别CHAR
       case 21:
           c=nextChar();
           if((c=='\''))
             state=22;
           else state=fail();
           System.out.println("state 21");
           break;
       case 22:
           c=nextChar();
           if(isLetter(c))
             state=23;
           break;
       case 23:
           c=nextChar();
           if((c=='\''))
             state=24;
           break;
       case 24:
           theid=buffer.substring(begining,ending);
           table.insert( theid , theid.length()-2 ,"字符型","常数","");
           return "Char";
       //识别不等式
       case 25:
           c=nextChar();
           if((c=='<'))
             state=26;
           else if((c=='='))
             state=30;
           else if((c=='>'))
             state=31;
           else state=fail();
           System.out.println("state 25");
           break;
       case 26:
          c=nextChar();
          if( (c=='=') )
            state=27;
          else if((c=='>'))
            state=28;
          else state=29;
          break;
       case 27:
            
          theid = buffer.substring(begining,ending);
          table.insert(theid,1000,"","","");
          return "<=";
       case 28:
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return "<>";
       case 29:
          ungetChar();
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return "<";
       case 30:
          System.out.println("state 30");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return "=";
       case 31:
          c=nextChar();
          if((c=='='))
           state=32;
          else 
           state=33;
          break;
       case 32:
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return ">=";
       case 33:
          System.out.println("state 33");
          ungetChar();
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return ">";
       
       //识别算术符号
       case 34:
          c=nextChar();
          if((c=='+'))
            state=35;
          else if((c=='-'))
            state=36;
          else if((c=='*'))
            state=37;
          else if((c=='/'))
            state=38;
          else state=fail();
          System.out.println("state 34");
          break;
        case 35:
          System.out.println("state 35"); 
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");   
          return "+";
        case 36:
          System.out.println("state 36");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return "-";
        case 37:
          System.out.println("state 37");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return "*";
        case 38:
          System.out.println("state 38");
            theid = buffer.substring(begining,ending);
            table.insert(theid,1000,"","","");
          return "/";
     }//end of switch
    }//end of while
  }//end nextToken
  
  int fail()
  {
     int start=-1;
     
     ending--;
     switch(state)
     {
        case 0:  start=3;  break;
        case 3:  start=6;  break;