/** * Helper class to deal with parsing the characters */class MailDateParser {        int index = 0;    char[] orig = null;    public MailDateParser(char[] orig) {	this.orig = orig;    }    /**     * skips chars until it finds a number (0-9)     *     * if it does not find a number, it will throw     * an ArrayIndexOutOfBoundsException     */	    public void skipUntilNumber() throws ParseException {	try {	    while (true) {		switch ( orig[index] ) {		case '0':		case '1':		case '2':		case '3':		case '4':		case '5':		case '6':		case '7':		case '8':		case '9':		    return;						default:		    index++;		    break;			}	    }	} catch (ArrayIndexOutOfBoundsException e) {	    throw new ParseException("No Number Found", index);	}    }    /**     * skips any number of tabs, spaces, CR, and LF - folding whitespace     */    public void skipWhiteSpace() {	int len = orig.length;	while (index < len) {	    switch (orig[index]) {	    case ' ': // space	    case '\t': // tab	    case '\r': // CR	    case '\n': // LF		index++;		break;						    default:		return;	    }		}    }    /**     * used to look at the next character without "parsing" that     * character.     */    public int peekChar() throws ParseException {	if (index < orig.length)	    return orig[index];	else	    throw new ParseException("No more characters", index);    }	    /**     * skips the given character.  if the current char does not     * match a ParseException will be thrown     */    public void skipChar(char c) throws ParseException {	if (index < orig.length) {	    if (orig[index] == c) {		index++;	    } else {		throw new ParseException("Wrong char", index);	    }	} else {	    throw new ParseException("No more characters", index);	}    }    /**     * will only skip the current char if it matches the given     * char     */    public boolean skipIfChar(char c) throws ParseException {	if (index < orig.length) {	    if (orig[index] == c) {		index++;		return true;	    } else {		return false;	    }	} else {	    throw new ParseException("No more characters", index);	}    }   	    /**     * current char must point to a number.  the number will be     * parsed and the resulting number will be returned.  if a     * number is not found, a ParseException will be thrown     */    public int parseNumber() throws ParseException {	int length = orig.length;	boolean gotNum = false;	int result = 0;					while (index < length) {	    switch( orig[index] ) {		case '0':		    result *= 10;		    gotNum = true;		    break;		    		case '1':		    result = result * 10 + 1;		    gotNum = true;		    break;		    		case '2':		    result = result * 10 + 2;		    gotNum = true;		    break;		    		case '3':		    result = result * 10 + 3;		    gotNum = true;		    break;		    		case '4':		    result = result * 10 + 4;		    gotNum = true;		    break;		    		case '5':		    result = result * 10 + 5;		    gotNum = true;		    break;		    		case '6':		    result = result * 10 + 6;		    gotNum = true;		    break;		    		case '7':		    result = result * 10 + 7;		    gotNum = true;		    break;		    		case '8':		    result = result * 10 + 8;		    gotNum = true;		    break;		    		case '9':		    result = result * 10 + 9;		    gotNum = true;		    break;			default:		    if (gotNum)			return result;		    else			throw new ParseException("No Number found", index);	    }	    	    index++;	}			// check the result	if (gotNum)	    return result;				// else, throw a parse error	throw new ParseException("No Number found", index);    }	    /**     * will look for one of "Jan/Feb/Mar/Apr/May/Jun/Jul/Aug/Sep/Oct/Nov/Dev"     * and return the numerical version of the month. (0-11).  a ParseException     * error is thrown if a month cannot be found.     */    public int parseMonth() throws ParseException {	char curr;			try {	    switch(orig[index++]) {	    case 'J':	    case 'j': // "Jan" (0) /  "Jun" (5) /  "Jul" (6)		// check next char		switch(orig[index++]) {		case 'A':		case 'a':		    curr = orig[index++];		    if (curr == 'N' || curr == 'n') {			return 0;		    }		    break;									case 'U':		case 'u':		    curr = orig[index++];		    if (curr == 'N' || curr == 'n') {			return 5;		    } else if (curr == 'L' || curr == 'l') {			return 6;		    }		    break;		}		break;					    case 'F':	    case 'f': // "Feb"		curr = orig[index++];		if (curr == 'E' || curr == 'e') {		    curr = orig[index++];		    if (curr == 'B' || curr == 'b') {			return 1;		    }		}		break;					    case 'M':	    case 'm': // "Mar" (2) /  "May" (4)		curr = orig[index++];		if (curr == 'A' || curr == 'a') {		    curr = orig[index++];		    if (curr == 'R' || curr == 'r') {			return 2;		    } else if (curr == 'Y' || curr == 'y') {			return 4;		    }		}		break;								    case 'A':	    case 'a': // "Apr" (3) /  "Aug" (7)		curr = orig[index++];		if (curr == 'P' || curr == 'p') {		    curr = orig[index++];		    if (curr == 'R' || curr == 'r') {			return 3;		    }		} else if (curr == 'U' || curr == 'u') {		    curr = orig[index++];		    if (curr == 'G' || curr == 'g') {			return 7;		    }		}		break;								    case 'S':	    case 's': // "Sep" (8)		curr = orig[index++];		if (curr == 'E' || curr == 'e') {		    curr = orig[index++];		    if (curr == 'P' || curr == 'p') {			return 8;		    }		}		break;								    case 'O':	    case 'o': // "Oct"		curr = orig[index++];		if (curr == 'C' || curr == 'c') {		    curr = orig[index++];		    if (curr == 'T' || curr == 't') {			return 9;		    }		}		break;								    case 'N':	    case 'n': // "Nov"		curr = orig[index++];		if (curr == 'O' || curr == 'o') {		    curr = orig[index++];		    if (curr == 'V' || curr == 'v') {			return 10;		    }		}		break;				    case 'D':	    case 'd': // "Dec"		curr = orig[index++];		if (curr == 'E' || curr == 'e') {		    curr = orig[index++];		    if (curr == 'C' || curr == 'c') {			return 11;		    }		}		break;		    }	} catch (ArrayIndexOutOfBoundsException e) {	}			throw new ParseException("Bad Month", index);    }	    /**     * will parse the timezone - either Numerical version (e.g. +0800, -0500)     * or the alpha version (e.g. PDT, PST).  the result will be returned in     * minutes needed to be added to the date to bring it to GMT.     */    public int parseTimeZone() throws ParseException {	if (index >= orig.length) 	    throw new ParseException("No more characters", index);			char test = orig[index];	if ( test == '+' || test == '-' ) {	    return parseNumericTimeZone();	} else {	    return parseAlphaTimeZone();	}    }        /**     * will parse the Numerical time zone version (e.g. +0800, -0500)     * the result will be returned in minutes needed to be added     * to the date to bring it to GMT.     */    public int parseNumericTimeZone() throws ParseException {	// we switch the sign if it is a '+'	// since the time in the string we are	// parsing is off from GMT by that amount.	// and we want to get the time back into	// GMT, so we substract it.	boolean switchSign = false;	char first = orig[index++];	if (first == '+') {	    switchSign = true;	} else if (first != '-') {	    throw new ParseException("Bad Numeric TimeZone", index);		}			int tz = parseNumber();	int offset = (tz / 100) * 60  + (tz % 100);	if (switchSign) {	    return -offset;	} else {	    return offset;	}    }    /**     * will parse the alpha time zone version (e.g. PDT, PST).     * the result will be returned in minutes needed to be added     * to the date to bring it to GMT.     */    public int parseAlphaTimeZone() throws ParseException {	int result = 0;	boolean foundCommon = false;	char curr;			try {	    switch(orig[index++]) {	    case 'U':	    case 'u': // "UT"	/	Universal Time		curr = orig[index++];		if (curr == 'T' || curr == 't') {		    result = 0;		    break;		}		throw new ParseException("Bad Alpha TimeZone", index);						    case 'G':	    case 'g': // "GMT" ; Universal Time		curr = orig[index++];		if (curr == 'M' || curr == 'm') {		    curr = orig[index++];		    if (curr == 'T' || curr == 't') {			result = 0;			break;		    }				}		throw new ParseException("Bad Alpha TimeZone", index);							    case 'E':	    case 'e': // "EST" / "EDT" ;  Eastern:  - 5/ - 4		result = 300;		foundCommon = true;		break;						    case 'C':	    case 'c': // "CST" / "CDT" ;  Central:  - 6/ - 5		result = 360;		foundCommon = true;		break;						    case 'M':	    case 'm': // "MST" / "MDT" ;  Mountain: - 7/ - 6		result = 420;		foundCommon = true;		break;						    case 'P':	    case 'p': // "PST" / "PDT" ;  Pacific:  - 8/ - 7 		result = 480;		foundCommon = true;		break;	    default:		throw new ParseException("Bad Alpha TimeZone", index);	    }	} catch (ArrayIndexOutOfBoundsException e) {	    throw new ParseException("Bad Alpha TimeZone", index);	}			if (foundCommon) {	    curr = orig[index++];	    if (curr == 'S' || curr == 's') {		curr = orig[index++];		if (curr != 'T' && curr != 't') {		    throw new ParseException("Bad Alpha TimeZone", index);		}	    } else if (curr == 'D' || curr == 'd') {		curr = orig[index++];		if (curr == 'T' || curr != 't') {		    // for daylight time		    result -= 60;		} else {		    throw new ParseException("Bad Alpha TimeZone", index);		}	    }	}	return result;    }    int getIndex() {	return index;    }}