reservedwordtable.java~25~

我用java写的词法分析器

package 编译技术;

import java.util.*;

public class ReservedWordTable
{
  private Hashtable reservedWordTable = new Hashtable(19);
  public ReservedWordTable()
  {
    reservedWordTable.put("0", "#");
    reservedWordTable.put("1", "begin");
    reservedWordTable.put("2", "if");
    reservedWordTable.put("3", "then");
    reservedWordTable.put("4", "while");
    reservedWordTable.put("5", "do");
    reservedWordTable.put("6", "end");
    reservedWordTable.put("13", "+");
    reservedWordTable.put("14", "-");
    reservedWordTable.put("15", "*");
    reservedWordTable.put("16", "/");
    reservedWordTable.put("17", ":=");
    reservedWordTable.put("18", ";");
    reservedWordTable.put("20", "<");
    reservedWordTable.put("21", "<>");
    reservedWordTable.put("22", "<=");
    reservedWordTable.put("23", ">");
    reservedWordTable.put("24", ">=");
    reservedWordTable.put("25", "=");
  }

  public boolean isKeyWord(String inw)
  {
    String resWord;
    //查找hash表
    for (Enumeration e = reservedWordTable.elements(); e.hasMoreElements(); )
    {
      resWord = (String) e.nextElement();
      if (resWord.equalsIgnoreCase(inw))
      {
        return true;
      }
    }
    return false;
  }

  /*public int getKeyWordType(String inw)
     {
    String resWord;
    int index=0;
    int type=1000;
    //查找hash表
    for (Enumeration e = reservedWordTable.elements(); e.hasMoreElements(); )
    {
      resWord = (String) e.nextElement();
      if (resWord.equalsIgnoreCase(inw))
      {
        if (inw.equals("#"))
        {
          type = 0;
        }
        else if (inw.equals("begin"))
        {
          type = 1;
        }
        else if (inw.equals("if"))
        {
          type = 2;
        }
        else if (inw.equals("then"))
        {
          type = 3;
        }
        else if (inw.equals("while"))
        {
          type = 4;
        }
        else if (inw.equals("do"))
        {
          type = 5;
        }

        else if (inw.equals("end"))
        {
          type = 6;
        }
        else if (inw.equals("+"))
        {
          type = 13;
        }
        else if (inw.equals("-"))
        {
          type = 14;
        }
        else if (inw.equals("*"))
        {
          type = 15;
        }

        else if (inw.equals("/"))
        {
          type = 16;
        }
        else if (inw.equals(":="))
        {
          type = 17;
        }
        else if (inw.equals(";"))
        {
          type = 18;
        }
        else if (inw.equals("<"))
        {
          type = 20;
        }
        else if (inw.equals("<>"))
        {
          type = 21;
        }
        else if (inw.equals("<="))
        {
          type = 22;
        }
        else if (inw.equals(">"))
        {
          type = 23;
        }
        else if (inw.equals(">="))
        {
          type = 24;
        }
        else if (inw.equals("="))
        {
          type = 25;
        }
      }
      //******************

          index++;
       }
       return type;
       //return 1000;
        }*/
   //查找类型种别码

   public int getKeyWordType(String classWord)
   {
     int KEY;
     for (Enumeration e = this.reservedWordTable.keys(); e.hasMoreElements(); )
     {
       KEY = Integer.parseInt( (String) e.nextElement());
       if ( ( (String)this.reservedWordTable.get(Integer.toString(KEY))).
           equalsIgnoreCase(classWord))
       {
         return KEY;
       }
     }
     return -1;
   }
}