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📄 samplelexer.java

📁 SkipOOMiniJOOL教学语言的编译器前端
💻 JAVA
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/* The following code was generated by JFlex 1.4.1 on 07-3-24 下午7:15 */

package edu.ustc.cs.minijool.lexer;

/**
 * This class is a scanner generated by 
 * <a href="http://www.jflex.de/">JFlex</a> 1.4.1
 * on 07-3-24 下午7:15 from the specification file
 * <tt>D:/PL/manuscript/编译原理实践/初稿/proj/workspace/3.1.0/Lab2/JFlex/sample.flex</tt>
 */
public class SampleLexer {

  /** This character denotes the end of file */
  public static final int YYEOF = -1;

  /** initial size of the lookahead buffer */
  private static final int ZZ_BUFFERSIZE = 16384;

  /** lexical states */
  public static final int YYINITIAL = 0;

  /** 
   * Translates characters to character classes
   */
  private static final char [] ZZ_CMAP = {
     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  0,  0,  0,  0,  0,  0, 
     0,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, 
     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  0,  0,  0,  0,  0, 
     0,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, 
     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  0,  0,  0,  0,  0
  };

  /** 
   * Translates DFA states to action switch labels.
   */
  private static final int [] ZZ_ACTION = zzUnpackAction();

  private static final String ZZ_ACTION_PACKED_0 =
    "\1\0\1\1\1\2\1\3";

  private static int [] zzUnpackAction() {
    int [] result = new int[4];
    int offset = 0;
    offset = zzUnpackAction(ZZ_ACTION_PACKED_0, offset, result);
    return result;
  }

  private static int zzUnpackAction(String packed, int offset, int [] result) {
    int i = 0;       /* index in packed string  */
    int j = offset;  /* index in unpacked array */
    int l = packed.length();
    while (i < l) {
      int count = packed.charAt(i++);
      int value = packed.charAt(i++);
      do result[j++] = value; while (--count > 0);
    }
    return j;
  }


  /** 
   * Translates a state to a row index in the transition table
   */
  private static final int [] ZZ_ROWMAP = zzUnpackRowMap();

  private static final String ZZ_ROWMAP_PACKED_0 =
    "\0\0\0\3\0\6\0\11";

  private static int [] zzUnpackRowMap() {
    int [] result = new int[4];
    int offset = 0;
    offset = zzUnpackRowMap(ZZ_ROWMAP_PACKED_0, offset, result);
    return result;
  }

  private static int zzUnpackRowMap(String packed, int offset, int [] result) {
    int i = 0;  /* index in packed string  */
    int j = offset;  /* index in unpacked array */
    int l = packed.length();
    while (i < l) {
      int high = packed.charAt(i++) << 16;
      result[j++] = high | packed.charAt(i++);
    }
    return j;
  }

  /** 
   * The transition table of the DFA
   */
  private static final int [] ZZ_TRANS = zzUnpackTrans();

  private static final String ZZ_TRANS_PACKED_0 =
    "\1\2\1\3\1\4\4\0\1\3\3\0\1\4";

  private static int [] zzUnpackTrans() {
    int [] result = new int[12];
    int offset = 0;
    offset = zzUnpackTrans(ZZ_TRANS_PACKED_0, offset, result);
    return result;
  }

  private static int zzUnpackTrans(String packed, int offset, int [] result) {
    int i = 0;       /* index in packed string  */
    int j = offset;  /* index in unpacked array */
    int l = packed.length();
    while (i < l) {
      int count = packed.charAt(i++);
      int value = packed.charAt(i++);
      value--;
      do result[j++] = value; while (--count > 0);
    }
    return j;
  }


  /* error codes */
  private static final int ZZ_UNKNOWN_ERROR = 0;
  private static final int ZZ_NO_MATCH = 1;
  private static final int ZZ_PUSHBACK_2BIG = 2;

  /* error messages for the codes above */
  private static final String ZZ_ERROR_MSG[] = {
    "Unkown internal scanner error",
    "Error: could not match input",
    "Error: pushback value was too large"
  };

  /**
   * ZZ_ATTRIBUTE[aState] contains the attributes of state <code>aState</code>
   */
  private static final int [] ZZ_ATTRIBUTE = zzUnpackAttribute();

  private static final String ZZ_ATTRIBUTE_PACKED_0 =
    "\1\0\1\11\2\1";

  private static int [] zzUnpackAttribute() {
    int [] result = new int[4];
    int offset = 0;
    offset = zzUnpackAttribute(ZZ_ATTRIBUTE_PACKED_0, offset, result);
    return result;
  }

  private static int zzUnpackAttribute(String packed, int offset, int [] result) {
    int i = 0;       /* index in packed string  */
    int j = offset;  /* index in unpacked array */
    int l = packed.length();
    while (i < l) {
      int count = packed.charAt(i++);
      int value = packed.charAt(i++);
      do result[j++] = value; while (--count > 0);
    }
    return j;
  }

  /** the input device */
  private java.io.Reader zzReader;

  /** the current state of the DFA */
  private int zzState;

  /** the current lexical state */
  private int zzLexicalState = YYINITIAL;

  /** this buffer contains the current text to be matched and is
      the source of the yytext() string */
  private char zzBuffer[] = new char[ZZ_BUFFERSIZE];

  /** the textposition at the last accepting state */
  private int zzMarkedPos;

  /** the textposition at the last state to be included in yytext */
  private int zzPushbackPos;

  /** the current text position in the buffer */
  private int zzCurrentPos;

  /** startRead marks the beginning of the yytext() string in the buffer */
  private int zzStartRead;

  /** endRead marks the last character in the buffer, that has been read
      from input */
  private int zzEndRead;

  /** number of newlines encountered up to the start of the matched text */
  private int yyline;

  /** the number of characters up to the start of the matched text */
  private int yychar;

  /**
   * the number of characters from the last newline up to the start of the 
   * matched text
   */
  private int yycolumn;

  /** 
   * zzAtBOL == true <=> the scanner is currently at the beginning of a line
   */
  private boolean zzAtBOL = true;

  /** zzAtEOF == true <=> the scanner is at the EOF */
  private boolean zzAtEOF;

  /* user code: */
	public static void main(String argv[]) {
		if (argv.length != 1) {
			System.out.println	("Usage: java SampleLexer inputfile");
		}
		else {
			SampleLexer l =null;
			try	{
				l = new SampleLexer(new java.io.FileReader(argv[0]));
				Symbol s = l.yylex();
				while (s.getType() != Symbol.EOF) {
					System.out.println(s);
					s = l.yylex();
				}
			} catch (Exception e) {
				System.out.println("Unexpected exception:");
				e.printStackTrace();
			}
		}
	}

	private Symbol symbol(int type) {
		return new Symbol(type, yytext(), yyline, yycolumn);
	}


  /**
   * Creates a new scanner
   * There is also a java.io.InputStream version of this constructor.
   *
   * @param   in  the java.io.Reader to read input from.
   */
  public SampleLexer(java.io.Reader in) {
    this.zzReader = in;
  }

  /**
   * Creates a new scanner.
   * There is also java.io.Reader version of this constructor.
   *
   * @param   in  the java.io.Inputstream to read input from.
   */
  public SampleLexer(java.io.InputStream in) {
    this(new java.io.InputStreamReader(in));
  }


  /**
   * Refills the input buffer.
   *
   * @return      <code>false</code>, iff there was new input.
   * 
   * @exception   java.io.IOException  if any I/O-Error occurs
   */
  private boolean zzRefill() throws java.io.IOException {

    /* first: make room (if you can) */
    if (zzStartRead > 0) {
      System.arraycopy(zzBuffer, zzStartRead,
                       zzBuffer, 0,
                       zzEndRead-zzStartRead);

      /* translate stored positions */
      zzEndRead-= zzStartRead;
      zzCurrentPos-= zzStartRead;
      zzMarkedPos-= zzStartRead;
      zzPushbackPos-= zzStartRead;
      zzStartRead = 0;
    }

    /* is the buffer big enough? */
    if (zzCurrentPos >= zzBuffer.length) {
      /* if not: blow it up */
      char newBuffer[] = new char[zzCurrentPos*2];
      System.arraycopy(zzBuffer, 0, newBuffer, 0, zzBuffer.length);
      zzBuffer = newBuffer;
    }

    /* finally: fill the buffer with new input */
    int numRead = zzReader.read(zzBuffer, zzEndRead,
                                            zzBuffer.length-zzEndRead);

    if (numRead < 0) {
      return true;

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