yylex.java~

tiger run time supporting files

/* The following code was generated by JFlex 1.4 on 06-4-6 上午12:49 */

package tiger.parse;

import tiger.errormsg.ErrorMsg;

/**
 * This class is a scanner generated by <a href="http://www.jflex.de/">JFlex</a>
 * 1.4 on 06-4-6 上午12:49 from the specification file
 * <tt>D:/workspace/tiger/tiger/parse/Tiger.flex</tt>
 */
class Yylex {

	/** 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;

	public static final int COMMENT = 1;

	/**
	 * Translates characters to character classes
	 */
	private static final char[] ZZ_CMAP = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 0,
			3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0,
			0, 0, 0, 0, 0, 0, 0, 0, 13, 11, 9, 0, 10, 12, 8, 8, 8, 8, 8, 8, 8,
			8, 8, 8, 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, 5, 0, 0, 4, 0, 0, 0, 0, 0, 6, 0, 0, 7, 0, 0, 0, 0, 0, 0,
			0, 0, 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 = "\2\0\1\1\2\2\1\3\2\1\1\4\1\5\1\6"
			+ "\1\7\1\1\1\10\1\11\1\0\1\12\1\13";

	private static int[] zzUnpackAction() {
		int[] result = new int[18];
		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\16\0\34\0\52\0\34\0\34\0\70\0\106"
			+ "\0\124\0\34\0\34\0\34\0\142\0\34\0\34\0\160" + "\0\34\0\34";

	private static int[] zzUnpackRowMap() {
		int[] result = new int[18];
		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\3\1\4\1\5\1\6\1\7\1\10\2\3\1\11"
			+ "\1\12\1\13\1\14\1\15\1\3\16\16\20\0\1\5"
			+ "\20\0\1\17\16\0\1\20\17\0\1\11\22\0\1\21" + "\7\0\1\22\6\0";

	private static int[] zzUnpackTrans() {
		int[] result = new int[126];
		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 = "\2\0\1\11\1\1\2\11\3\1\3\11\1\1\2\11"
			+ "\1\0\2\11";

	private static int[] zzUnpackAttribute() {
		int[] result = new int[18];
		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: */

	private void newline() {
		errorMsg.newline(yychar);
	}

	private void err(int pos, String s) {
		errorMsg.error(pos, s);
	}

	private void err(String s) {
		err(yychar, s);
	}

	private java_cup.runtime.Symbol tok(int kind, Object value) {
		return new java_cup.runtime.Symbol(kind, yychar, yychar + yylength(),
				value);
	}

	public Yylex(java.io.InputStream s, ErrorMsg e) {
		this(s);
		errorMsg = e;
	}

	private ErrorMsg errorMsg;

	/**
	 * 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.
	 */
	Yylex(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.
	 */
	Yylex(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;
		} else {
			zzEndRead += numRead;
			return false;
		}
	}

	/**
	 * Closes the input stream.
	 */
	public final void yyclose() throws java.io.IOException {
		zzAtEOF = true; /* indicate end of file */
		zzEndRead = zzStartRead; /* invalidate buffer */

		if (zzReader != null)
			zzReader.close();
	}

	/**
	 * Resets the scanner to read from a new input stream. Does not close the
	 * old reader.
	 * 
	 * All internal variables are reset, the old input stream <b>cannot</b> be
	 * reused (internal buffer is discarded and lost). Lexical state is set to
	 * <tt>ZZ_INITIAL</tt>.
	 * 
	 * @param reader
	 *            the new input stream
	 */
	public final void yyreset(java.io.Reader reader) {
		zzReader = reader;
		zzAtBOL = true;
		zzAtEOF = false;
		zzEndRead = zzStartRead = 0;
		zzCurrentPos = zzMarkedPos = zzPushbackPos = 0;
		yyline = yychar = yycolumn = 0;
		zzLexicalState = YYINITIAL;
	}

	/**
	 * Returns the current lexical state.
	 */
	public final int yystate() {
		return zzLexicalState;
	}

	/**
	 * Enters a new lexical state
	 * 
	 * @param newState
	 *            the new lexical state
	 */
	public final void yybegin(int newState) {
		zzLexicalState = newState;
	}

	/**
	 * Returns the text matched by the current regular expression.
	 */
	public final String yytext() {
		return new String(zzBuffer, zzStartRead, zzMarkedPos - zzStartRead);
	}

	/**
	 * Returns the character at position <tt>pos</tt> from the matched text.
	 * 
	 * It is equivalent to yytext().charAt(pos), but faster
	 * 
	 * @param pos
	 *            the position of the character to fetch. A value from 0 to
	 *            yylength()-1.
	 * 
	 * @return the character at position pos
	 */
	public final char yycharat(int pos) {
		return zzBuffer[zzStartRead + pos];
	}

	/**
	 * Returns the length of the matched text region.
	 */
	public final int yylength() {
		return zzMarkedPos - zzStartRead;
	}

	/**
	 * Reports an error that occured while scanning.
	 * 
	 * In a wellformed scanner (no or only correct usage of yypushback(int) and
	 * a match-all fallback rule) this method will only be called with things
	 * that "Can't Possibly Happen". If this method is called, something is
	 * seriously wrong (e.g. a JFlex bug producing a faulty scanner etc.).
	 * 
	 * Usual syntax/scanner level error handling should be done in error
	 * fallback rules.
	 * 
	 * @param errorCode
	 *            the code of the errormessage to display
	 */
	private void zzScanError(int errorCode) {
		String message;
		try {
			message = ZZ_ERROR_MSG[errorCode];
		} catch (ArrayIndexOutOfBoundsException e) {
			message = ZZ_ERROR_MSG[ZZ_UNKNOWN_ERROR];
		}

		throw new Error(message);
	}

	/**
	 * Pushes the specified amount of characters back into the input stream.
	 * 
	 * They will be read again by then next call of the scanning method
	 * 
	 * @param number
	 *            the number of characters to be read again. This number must
	 *            not be greater than yylength()!
	 */
	public void yypushback(int number) {
		if (number > yylength())
			zzScanError(ZZ_PUSHBACK_2BIG);

		zzMarkedPos -= number;
	}

	/**
	 * Resumes scanning until the next regular expression is matched, the end of
	 * input is encountered or an I/O-Error occurs.
	 * 
	 * @return the next token
	 * @exception java.io.IOException
	 *                if any I/O-Error occurs
	 */
	public java_cup.runtime.Symbol yylex() throws java.io.IOException {
		int zzInput;
		int zzAction;

		// cached fields:
		int zzCurrentPosL;
		int zzMarkedPosL;
		int zzEndReadL = zzEndRead;
		char[] zzBufferL = zzBuffer;
		char[] zzCMapL = ZZ_CMAP;

		int[] zzTransL = ZZ_TRANS;
		int[] zzRowMapL = ZZ_ROWMAP;
		int[] zzAttrL = ZZ_ATTRIBUTE;

		while (true) {
			zzMarkedPosL = zzMarkedPos;

			yychar += zzMarkedPosL - zzStartRead;

			zzAction = -1;

			zzCurrentPosL = zzCurrentPos = zzStartRead = zzMarkedPosL;

			zzState = zzLexicalState;

			zzForAction: {
				while (true) {

					if (zzCurrentPosL < zzEndReadL)
						zzInput = zzBufferL[zzCurrentPosL++];
					else if (zzAtEOF) {
						zzInput = YYEOF;
						break zzForAction;
					} else {
						// store back cached positions
						zzCurrentPos = zzCurrentPosL;
						zzMarkedPos = zzMarkedPosL;
						boolean eof = zzRefill();
						// get translated positions and possibly new buffer
						zzCurrentPosL = zzCurrentPos;
						zzMarkedPosL = zzMarkedPos;
						zzBufferL = zzBuffer;
						zzEndReadL = zzEndRead;
						if (eof) {
							zzInput = YYEOF;
							break zzForAction;
						} else {
							zzInput = zzBufferL[zzCurrentPosL++];
						}
					}
					int zzNext = zzTransL[zzRowMapL[zzState] + zzCMapL[zzInput]];
					if (zzNext == -1)
						break zzForAction;
					zzState = zzNext;

					int zzAttributes = zzAttrL[zzState];
					if ((zzAttributes & 1) == 1) {
						zzAction = zzState;
						zzMarkedPosL = zzCurrentPosL;
						if ((zzAttributes & 8) == 8)
							break zzForAction;
					}

				}
			}

			// store back cached position
			zzMarkedPos = zzMarkedPosL;

			switch (zzAction < 0 ? zzAction : ZZ_ACTION[zzAction]) {
			case 6: {
				return tok(sym.DOT, null);
			}
			case 12:
				break;
			case 10: {
				yybegin(COMMENT);
			}
			case 13:
				break;
			case 8: { /* nothing */
			}
			case 14:
				break;
			case 2: {
				newline();
			}
			case 15:
				break;
			case 9: {
				return tok(sym.IF, null);
			}
			case 16:
				break;
			case 4: {
				return tok(sym.INT, new Integer(yytext()));
			}
			case 17:
				break;
			case 3: { /* do nothing */
			}
			case 18:
				break;
			case 1: {
				return tok(sym.error, yytext());
			}
			case 19:
				break;
			case 7: {
				return tok(sym.PLUS, null);
			}
			case 20:
				break;
			case 11: {
				return tok(sym.FOR, null);
			}
			case 21:
				break;
			case 5: {
				return tok(sym.COMMA, null);
			}
			case 22:
				break;
			default:
				if (zzInput == YYEOF && zzStartRead == zzCurrentPos) {
					zzAtEOF = true;
					{
						{
							return tok(sym.EOF, null);
						}
					}
				} else {
					zzScanError(ZZ_NO_MATCH);
				}
			}
		}
	}

}