lexer.java

有关编译器的编译器.

/* This file was generated by SableCC (http://www.sablecc.org/). */

package org.sablecc.sablecc.lexer;

import java.io.*;
import java.util.*;
import org.sablecc.sablecc.node.*;

public class Lexer
{
  protected Token token;
  protected State state = State.NORMAL;

  private PushbackReader in;
  private int line;
  private int pos;
  private boolean cr;
  private boolean eof;
  private final StringBuffer text = new StringBuffer();

  protected void filter() throws LexerException, IOException
    {}

  public Lexer(PushbackReader in)
  {
    this.in = in;

    if(gotoTable == null)
    {
      try
      {
        DataInputStream s = new DataInputStream(
                              new BufferedInputStream(
                                Lexer.class.getResourceAsStream("lexer.dat")));

        // read gotoTable
        int length = s.readInt();
        gotoTable = new int[length][][][];
        for(int i = 0; i < gotoTable.length; i++)
        {
          length = s.readInt();
          gotoTable[i] = new int[length][][];
          for(int j = 0; j < gotoTable[i].length; j++)
          {
            length = s.readInt();
            gotoTable[i][j] = new int[length][3];
            for(int k = 0; k < gotoTable[i][j].length; k++)
            {
              for(int l = 0; l < 3; l++)
              {
                gotoTable[i][j][k][l] = s.readInt();
              }
            }
          }
        }

        // read accept
        length = s.readInt();
        accept = new int[length][];
        for(int i = 0; i < accept.length; i++)
        {
          length = s.readInt();
          accept[i] = new int[length];
          for(int j = 0; j < accept[i].length; j++)
          {
            accept[i][j] = s.readInt();
          }
        }

        s.close();
      }
      catch(Exception e)
      {
        throw new RuntimeException("The file \"lexer.dat\" is either missing or corrupted.");
      }
    }
  }

  public Token peek() throws LexerException, IOException
  {
    while(token == null)
    {
      token = getToken();
      filter();
    }

    return token;
  }

  public Token next() throws LexerException, IOException
  {
    while(token == null)
    {
      token = getToken();
      filter();
    }

    Token result = token;
    token = null;
    return result;
  }

  protected Token getToken() throws IOException, LexerException
  {
    int dfa_state = 0;

    int start_pos = pos;
    int start_line = line;

    int accept_state = -1;
    int accept_token = -1;
    int accept_length = -1;
    int accept_pos = -1;
    int accept_line = -1;

    int[][][] gotoTable = this.gotoTable[state.id()];
    int[] accept = this.accept[state.id()];
    text.setLength(0);

    while(true)
    {
      int c = getChar();

      if(c != -1)
      {
        switch(c)
        {
        case 10:
          if(cr)
          {
            cr = false;
          }
          else
          {
            line++;
            pos = 0;
          }
          break;
        case 13:
          line++;
          pos = 0;
          cr = true;
          break;
        default:
          pos++;
          cr = false;
          break;
        };

        text.append((char) c);

        do
        {
          int oldState = (dfa_state < -1) ? (-2 -dfa_state) : dfa_state;

          dfa_state = -1;

          int[][] tmp1 =  gotoTable[oldState];
          int low = 0;
          int high = tmp1.length - 1;

          while(low <= high)
          {
            int middle = (low + high) / 2;
            int[] tmp2 = tmp1[middle];

            if(c < tmp2[0])
            {
              high = middle - 1;
            }
            else if(c > tmp2[1])
            {
              low = middle + 1;
            }
            else
            {
              dfa_state = tmp2[2];
              break;
            }
          }
        }
        while(dfa_state < -1);
      }
      else
      {
        dfa_state = -1;
      }

      if(dfa_state >= 0)
      {
        if(accept[dfa_state] != -1)
        {
          accept_state = dfa_state;
          accept_token = accept[dfa_state];
          accept_length = text.length();
          accept_pos = pos;
          accept_line = line;
        }
      }
      else
      {
        if(accept_state != -1)
        {
          switch(accept_token)
          {
          case 0:
            {
              Token token = new0(
                              getText(accept_length),
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              switch(state.id())
              {
              case 1:
                state = State.PACKAGE;
                break;
              }
              return token;
            }
          case 1:
            {
              Token token = new1(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              switch(state.id())
              {
              case 0:
                state = State.PACKAGE;
                break;
              }
              return token;
            }
          case 2:
            {
              Token token = new2(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 3:
            {
              Token token = new3(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 4:
            {
              Token token = new4(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 5:
            {
              Token token = new5(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 6:
            {
              Token token = new6(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 7:
            {
              Token token = new7(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 8:
            {
              Token token = new8(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 9:
            {
              Token token = new9(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 10:
            {
              Token token = new10(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 11:
            {
              Token token = new11(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              switch(state.id())
              {
              case 0:
                state = State.NORMAL;
                break;
              case 1:
                state = State.NORMAL;
                break;
              }
              return token;
            }
          case 12:
            {
              Token token = new12(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 13:
            {
              Token token = new13(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 14:
            {
              Token token = new14(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 15:
            {
              Token token = new15(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 16:
            {
              Token token = new16(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 17:
            {
              Token token = new17(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 18:
            {
              Token token = new18(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 19:
            {
              Token token = new19(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 20:
            {
              Token token = new20(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 21:
            {
              Token token = new21(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 22:
            {
              Token token = new22(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 23:
            {
              Token token = new23(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 24:
            {
              Token token = new24(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 25:
            {
              Token token = new25(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 26:
            {
              Token token = new26(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 27:
            {
              Token token = new27(
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 28:
            {
              Token token = new28(
                              getText(accept_length),
                              start_line + 1,
                              start_pos + 1);
              pushBack(accept_length);
              pos = accept_pos;
              line = accept_line;
              return token;
            }
          case 29:
            {