/*
      Copyright (C) 2002-2004 MySQL AB

      This program is free software; you can redistribute it and/or modify
      it under the terms of version 2 of the GNU General Public License as 
      published by the Free Software Foundation.

      There are special exceptions to the terms and conditions of the GPL 
      as it is applied to this software. View the full text of the 
      exception in file EXCEPTIONS-CONNECTOR-J in the directory of this 
      software distribution.

      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      GNU General Public License for more details.

      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA



 */
package com.mysql.jdbc;

import java.io.ByteArrayOutputStream;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.math.BigDecimal;

import java.sql.SQLException;

import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;



/**
 * Various utility methods for converting to/from byte arrays in the platform
 * encoding
 *
 * @author Mark Matthews
 */
public class StringUtils {
    private static final int BYTE_RANGE = (1 + Byte.MAX_VALUE) -
        Byte.MIN_VALUE;
    private static byte[] allBytes = new byte[BYTE_RANGE];
    private static char[] byteToChars = new char[BYTE_RANGE];
    private static Method toPlainStringMethod;
    
    static {
        for (int i = Byte.MIN_VALUE; i <= Byte.MAX_VALUE; i++) {
            allBytes[i - Byte.MIN_VALUE] = (byte) i;
        }

        String allBytesString = new String(allBytes, 0,
                Byte.MAX_VALUE - Byte.MIN_VALUE);

        int allBytesStringLen = allBytesString.length();

        for (int i = 0;
                (i < (Byte.MAX_VALUE - Byte.MIN_VALUE)) &&
                (i < allBytesStringLen); i++) {
            byteToChars[i] = allBytesString.charAt(i);
        }
        
        try {
        	toPlainStringMethod = BigDecimal.class.getMethod("toPlainString", new Class[0]);
        } catch (NoSuchMethodException nsme) {
        	// that's okay, we fallback to .toString()
        } 
    }

    static final int WILD_COMPARE_MATCH_NO_WILD = 0;
    static final int WILD_COMPARE_MATCH_WITH_WILD = 1;
    static final int WILD_COMPARE_NO_MATCH = -1;
	

    /**
     * Returns the byte[] representation of the given string using given
     * encoding.
     *
     * @param s the string to convert
     * @param encoding the character encoding to use
     * @param parserKnowsUnicode DOCUMENT ME!
     *
     * @return byte[] representation of the string
     *
     * @throws SQLException if an encoding unsupported by the JVM is supplied.
     */
    public static final byte[] getBytes(String s, String encoding,
        String serverEncoding, boolean parserKnowsUnicode)
        throws SQLException {
        try {
            SingleByteCharsetConverter converter = SingleByteCharsetConverter.getInstance(encoding);

            return getBytes(s, converter, encoding, serverEncoding,
                parserKnowsUnicode);
        } catch (UnsupportedEncodingException uee) {
            throw new SQLException(Messages.getString("StringUtils.0") //$NON-NLS-1$
                 +encoding + Messages.getString("StringUtils.1"),
                SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
        }
    }

    /**
     * Returns the byte[] representation of the given string (re)using the
     * given charset converter, and the given encoding.
     *
     * @param s the string to convert
     * @param converter the converter to reuse
     * @param encoding the character encoding to use
     * @param serverEncoding DOCUMENT ME!
     * @param parserKnowsUnicode DOCUMENT ME!
     *
     * @return byte[] representation of the string
     *
     * @throws SQLException if an encoding unsupported by the JVM is supplied.
     */
    public static final byte[] getBytes(String s,
        SingleByteCharsetConverter converter, String encoding,
        String serverEncoding, boolean parserKnowsUnicode)
        throws SQLException {
        try {
            byte[] b = null;

            if (converter != null) {
                b = converter.toBytes(s);
            } else if (encoding == null) {
                b = s.getBytes();
            } else {
                b = s.getBytes(encoding);

                if (!parserKnowsUnicode &&
                        (encoding.equalsIgnoreCase("SJIS") //$NON-NLS-1$
                         ||encoding.equalsIgnoreCase("BIG5") //$NON-NLS-1$
                         ||encoding.equalsIgnoreCase("GBK"))) { //$NON-NLS-1$

                    if (!encoding.equalsIgnoreCase(serverEncoding)) {
                        b = escapeEasternUnicodeByteStream(b, s, 0, s.length());
                    }
                }
            }

            return b;
        } catch (UnsupportedEncodingException uee) {
            throw new SQLException(Messages.getString("StringUtils.5") //$NON-NLS-1$
                 +encoding + Messages.getString("StringUtils.6"),
                SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
        }
    }

    /**
     * DOCUMENT ME!
     *
     * @param s DOCUMENT ME!
     * @param converter DOCUMENT ME!
     * @param encoding DOCUMENT ME!
     * @param serverEncoding DOCUMENT ME!
     * @param offset DOCUMENT ME!
     * @param length DOCUMENT ME!
     * @param parserKnowsUnicode DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     *
     * @throws SQLException DOCUMENT ME!
     */
    public static final byte[] getBytes(String s,
        SingleByteCharsetConverter converter, String encoding,
        String serverEncoding, int offset, int length,
        boolean parserKnowsUnicode) throws SQLException {
        try {
            byte[] b = null;

            if (converter != null) {
                b = converter.toBytes(s, offset, length);
            } else if (encoding == null) {
                byte[] temp = s.getBytes();

                b = new byte[length];
                System.arraycopy(temp, offset, b, 0, length);
            } else {
                byte[] temp = s.getBytes(encoding);

                b = new byte[length];
                System.arraycopy(temp, offset, b, 0, length);

                if (!parserKnowsUnicode &&
                        (encoding.equalsIgnoreCase("SJIS") //$NON-NLS-1$
                         ||encoding.equalsIgnoreCase("BIG5") //$NON-NLS-1$
                         ||encoding.equalsIgnoreCase("GBK"))) { //$NON-NLS-1$

                    if (!encoding.equalsIgnoreCase(serverEncoding)) {
                        b = escapeEasternUnicodeByteStream(b, s, offset, length);
                    }
                }
            }

            return b;
        } catch (UnsupportedEncodingException uee) {
            throw new SQLException(Messages.getString("StringUtils.10") //$NON-NLS-1$
                 +encoding + Messages.getString("StringUtils.11"),
                SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
        }
    }

    /**
     * Dumps the given bytes to STDOUT as a hex dump (up to length bytes).
     *
     * @param byteBuffer the data to print as hex
     * @param length the number of bytes to print
     *
     * @return ...
     */
    public static final String dumpAsHex(byte[] byteBuffer, int length) {
        StringBuffer outputBuf = new StringBuffer(length * 4);

        int p = 0;
        int rows = length / 8;

        for (int i = 0; (i < rows) && (p < length); i++) {
            int ptemp = p;

            for (int j = 0; j < 8; j++) {
                String hexVal = Integer.toHexString(byteBuffer[ptemp] & 0xff);

                if (hexVal.length() == 1) {
                    hexVal = "0" + hexVal; //$NON-NLS-1$
                }

                outputBuf.append(hexVal + " "); //$NON-NLS-1$
                ptemp++;
            }

            outputBuf.append("    "); //$NON-NLS-1$

            for (int j = 0; j < 8; j++) {
                if ((byteBuffer[p] > 32) && (byteBuffer[p] < 127)) {
                    outputBuf.append((char) byteBuffer[p] + " "); //$NON-NLS-1$
                } else {
                    outputBuf.append(". "); //$NON-NLS-1$
                }

                p++;
            }

            outputBuf.append("\n"); //$NON-NLS-1$
        }

        int n = 0;

        for (int i = p; i < length; i++) {
            String hexVal = Integer.toHexString(byteBuffer[i] & 0xff);

            if (hexVal.length() == 1) {
                hexVal = "0" + hexVal; //$NON-NLS-1$
            }

            outputBuf.append(hexVal + " "); //$NON-NLS-1$
            n++;
        }

        for (int i = n; i < 8; i++) {
            outputBuf.append("   "); //$NON-NLS-1$
        }

        outputBuf.append("    "); //$NON-NLS-1$

        for (int i = p; i < length; i++) {
            if ((byteBuffer[i] > 32) && (byteBuffer[i] < 127)) {
                outputBuf.append((char) byteBuffer[i] + " "); //$NON-NLS-1$
            } else {
                outputBuf.append(". "); //$NON-NLS-1$
            }
        }

        outputBuf.append("\n"); //$NON-NLS-1$

        return outputBuf.toString();
    }

    /**
     * Splits stringToSplit into a list, using the given delimitter
     *
     * @param stringToSplit the string to split
     * @param delimitter the string to split on
     * @param trim should the split strings be whitespace trimmed?
     *
     * @return the list of strings, split by delimitter
     *
     * @throws IllegalArgumentException DOCUMENT ME!
     */
    public static final List split(String stringToSplit, String delimitter,
        boolean trim) {
        if (stringToSplit == null) {
            return new ArrayList();
        }

        if (delimitter == null) {
            throw new IllegalArgumentException();
        }

        StringTokenizer tokenizer = new StringTokenizer(stringToSplit,
                delimitter, false);

        List splitTokens = new ArrayList(tokenizer.countTokens());

        while (tokenizer.hasMoreTokens()) {
            String token = tokenizer.nextToken();

            if (trim) {
                token = token.trim();
            }

            splitTokens.add(token);
        }

        return splitTokens;
    }

    /**
     * Returns the bytes as an ASCII String.
     *
     * @param buffer the bytes representing the string
     *
     * @return The ASCII String.
     */
    public static final String toAsciiString(byte[] buffer) {
        return toAsciiString(buffer, 0, buffer.length);
    }

    /**
     * Returns the bytes as an ASCII String.
     *
     * @param buffer the bytes to convert
     * @param startPos the position to start converting
     * @param length the length of the string to convert
     *
     * @return the ASCII string
     */
    public static final String toAsciiString(byte[] buffer, int startPos,
        int length) {
        char[] charArray = new char[length];
        int readpoint = startPos;

        for (int i = 0; i < length; i++) {
            charArray[i] = (char) buffer[readpoint];
            readpoint++;
        }

        return new String(charArray);
    }

    /**
     * Unfortunately, SJIS has 0x5c as a high byte in some of its double-byte
     * characters, so we need to escape it.
     *
     * @param origBytes the original bytes in SJIS format
     * @param origString the string that had .getBytes() called on it
     * @param offset where to start converting from
     * @param length how many characters to convert.
     *
     * @return byte[] with 0x5c escaped
     */
    public static byte[] escapeEasternUnicodeByteStream(byte[] origBytes,
        String origString, int offset, int length) {
        if ((origBytes == null) || (origBytes.length == 0)) {
            return origBytes;
        }

        int bytesLen = origBytes.length;
        int bufIndex = 0;
        int strIndex = 0;

        ByteArrayOutputStream bytesOut = new ByteArrayOutputStream(bytesLen);

        while (true) {
            if (origString.charAt(strIndex) == '\\') {
                // write it out as-is
                bytesOut.write(origBytes[bufIndex++]);

                //bytesOut.write(origBytes[bufIndex++]);
            } else {
                // Grab the first byte
                int loByte = origBytes[bufIndex];

                if (loByte < 0) {
                    loByte += 256; // adjust for signedness/wrap-around
                }

                // We always write the first byte
                bytesOut.write(loByte);

                //
                // The codepage characters in question exist between
                // 0x81-0x9F and 0xE0-0xFC...
                //
                // See:
                //
                // http://www.microsoft.com/GLOBALDEV/Reference/dbcs/932.htm
                //
                // Problematic characters in GBK
                //
                // U+905C : CJK UNIFIED IDEOGRAPH
                //
                // Problematic characters in Big5
                //
                // B9F0 = U+5C62 : CJK UNIFIED IDEOGRAPH
                //
                if (loByte >= 0x80) {
                    if (bufIndex < (bytesLen - 1)) {
                        int hiByte = origBytes[bufIndex + 1];

                        if (hiByte < 0) {
                            hiByte += 256; // adjust for signedness/wrap-around
                        }

                        // write the high byte here, and increment the index
                        // for the high byte
                        bytesOut.write(hiByte);
                        bufIndex++;

                        // escape 0x5c if necessary
                        if (hiByte == 0x5C) {
                            bytesOut.write(hiByte);
                        }
                    }
                } else if (loByte == 0x5c) {
                    if (bufIndex < (bytesLen - 1)) {
                        int hiByte = origBytes[bufIndex + 1];

                        if (hiByte < 0) {
                            hiByte += 256; // adjust for signedness/wrap-around
                        }

                        if (hiByte == 0x62) {
                            // we need to escape the 0x5c
                            bytesOut.write(0x5c);
                            bytesOut.write(0x62);
                            bufIndex++;
                        }
                    }
                }

                bufIndex++;
            }

            if (bufIndex >= bytesLen) {
                // we're done
                break;
            }

            strIndex++;
        }

        return bytesOut.toByteArray();
    }

    /**
     * Returns the first non whitespace char, converted to upper case
     *
     * @param searchIn the string to search in
     *
     * @return the first non-whitespace character, upper cased.
     */
    public static char firstNonWsCharUc(String searchIn) {
        if (searchIn == null) {
            return 0;
        }

        int length = searchIn.length();

        for (int i = 0; i < length; i++) {
            char c = searchIn.charAt(i);

            if (!Character.isWhitespace(c)) {
                return Character.toUpperCase(c);
            }
        }

        return 0;
    }

    /**
     * DOCUMENT ME!
     *
     * @param searchIn DOCUMENT ME!
     * @param searchFor DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public static int indexOfIgnoreCase(String searchIn, String searchFor) {
        if ((searchIn == null) || (searchFor == null)) {
            return -1;
        }

        int patternLength = searchFor.length();
        int stringLength = searchIn.length();
        int stopSearchingAt = stringLength - patternLength;
        
        int i = 0;

        if (patternLength == 0) {
            return -1;
        }

        // Brute force string pattern matching
        // Some locales don't follow upper-case rule, so need to check both
        char firstCharOfPatternUc = Character.toUpperCase(searchFor.charAt(0));
        char firstCharOfPatternLc = Character.toLowerCase(searchFor.charAt(0));
        

lookForFirstChar: 
        while (true) {
            while ((i < stopSearchingAt) &&
                    (Character.toUpperCase(searchIn.charAt(i)) != firstCharOfPatternUc) &&
					 Character.toLowerCase(searchIn.charAt(i)) != firstCharOfPatternLc) {
                i++;
            }

            if (i > stopSearchingAt) {
                return -1;
            }

            int j = i + 1;
            int end = (j + patternLength) - 1;

            int k = 1; // start at second char of pattern

            while (j < end) {
            	int searchInPos = j++;
            	int searchForPos = k++;
            	
                if (Character.toUpperCase(searchIn.charAt(searchInPos)) != Character.toUpperCase(
                            searchFor.charAt(searchForPos))) {
                    i++;

                    // start over
                    continue lookForFirstChar;
                }
                
                // Georgian and Turkish locales don't have same convention, so need to check lowercase
                // too!
                if (Character.toLowerCase(searchIn.charAt(searchInPos)) != Character.toLowerCase(
                        searchFor.charAt(searchForPos))) {
                	i++;

                	// start over
                	continue lookForFirstChar;
                }
            }

            return i; // found entire pattern
        }
    }

    /**
     * Determines whether or not the string 'searchIn' contains the string
     * 'searchFor', dis-regarding case. Shorthand for a
     * String.regionMatch(...)
     *
     * @param searchIn the string to search in
     * @param searchFor the string to search for
     *
     * @return whether searchIn starts with searchFor, ignoring case
     */
    public static boolean startsWithIgnoreCase(String searchIn, String searchFor) {
        return startsWithIgnoreCase(searchIn, 0, searchFor);
    }

    /**
     * Determines whether or not the string 'searchIn' contains the string
     * 'searchFor', dis-regarding case starting at 'startAt' Shorthand for a
     * String.regionMatch(...)
     *
     * @param searchIn the string to search in
     * @param startAt the position to start at
     * @param searchFor the string to search for
     *
     * @return whether searchIn starts with searchFor, ignoring case
     */
    public static boolean startsWithIgnoreCase(String searchIn, int startAt,
        String searchFor) {
        return searchIn.regionMatches(true, 0, searchFor, startAt,
            searchFor.length());
    }

    /**
     * Determines whether or not the sting 'searchIn' contains the string
     * 'searchFor', di-regarding case and leading whitespace
     *
     * @param searchIn the string to search in
     * @param searchFor the string to search for
     *
     * @return true if the string starts with 'searchFor' ignoring whitespace
     */
    public static boolean startsWithIgnoreCaseAndWs(String searchIn,
        String searchFor) {
        if (searchIn == null) {
            return searchFor == null;
        }

        int beginPos = 0;

        int inLength = searchIn.length();

        for (beginPos = 0; beginPos < inLength; beginPos++) {
            if (!Character.isWhitespace(searchIn.charAt(beginPos))) {
                break;
            }
        }

        return startsWithIgnoreCase(searchIn, beginPos, searchFor);
    }

    /**
     * Compares searchIn against searchForWildcard with wildcards  (heavily
     * borrowed from strings/ctype-simple.c in the server sources)
     *
     * @param searchIn the string to search in
     * @param searchForWildcard the string to search for, using the 'standard'
     *        SQL wildcard chars of '%' and '_'
     *
     * @return WILD_COMPARE_MATCH_NO_WILD if matched, WILD_COMPARE_NO_MATCH if
     *         not matched with wildcard,  WILD_COMPARE_MATCH_WITH_WILD if
     *         matched with wildcard
     */
    public static int wildCompare(String searchIn, String searchForWildcard) {
        if ((searchIn == null) || (searchForWildcard == null)) {
            return WILD_COMPARE_NO_MATCH;
        }

        if (searchForWildcard.equals("%")) { //$NON-NLS-1$

            return WILD_COMPARE_MATCH_WITH_WILD;
        }

        int result = WILD_COMPARE_NO_MATCH; /* Not found, using wildcards */

        char wildcardMany = '%';
        char wildcardOne = '_';
        char wildcardEscape = '\\';

        int searchForPos = 0;
        int searchForEnd = searchForWildcard.length();

        int searchInPos = 0;
        int searchInEnd = searchIn.length();

        while (searchForPos != searchForEnd) {
            char wildstrChar = searchForWildcard.charAt(searchForPos);

            while ((searchForWildcard.charAt(searchForPos) != wildcardMany) &&
                    (wildstrChar != wildcardOne)) {
                if ((searchForWildcard.charAt(searchForPos) == wildcardEscape) &&
                        ((searchForPos + 1) != searchForEnd)) {
                    searchForPos++;
                }

                if ((searchInPos == searchInEnd) ||
                        (Character.toUpperCase(searchForWildcard.charAt(
                                searchForPos++)) != Character.toUpperCase(
                            searchIn.charAt(searchInPos++)))) {
                    return WILD_COMPARE_MATCH_WITH_WILD; /* No match */
                }

                if (searchForPos == searchForEnd) {
                    return ((searchInPos != searchInEnd)
                    ? WILD_COMPARE_MATCH_WITH_WILD : WILD_COMPARE_MATCH_NO_WILD); /* Match if both are at end */
                }

                result = WILD_COMPARE_MATCH_WITH_WILD; /* Found an anchor char     */
            }

            if (searchForWildcard.charAt(searchForPos) == wildcardOne) {
                do {
                    if (searchInPos == searchInEnd) { /* Skip one char if possible */

                        return (result);
                    }

                    searchInPos++;
                } while ((++searchForPos < searchForEnd) &&
                        (searchForWildcard.charAt(searchForPos) == wildcardOne));

                if (searchForPos == searchForEnd) {
                    break;
                }
            }

            if (searchForWildcard.charAt(searchForPos) == wildcardMany) { /* Found w_many */

                char cmp;

                searchForPos++;

                /* Remove any '%' and '_' from the wild search string */
                for (; searchForPos != searchForEnd; searchForPos++) {
                    if (searchForWildcard.charAt(searchForPos) == wildcardMany) {
                        continue;
                    }

                    if (searchForWildcard.charAt(searchForPos) == wildcardOne) {
                        if (searchInPos == searchInEnd) {
                            return (WILD_COMPARE_NO_MATCH);
                        }

                        searchInPos++;

                        continue;
                    }

                    break; /* Not a wild character */
                }

                if (searchForPos == searchForEnd) {
                    return WILD_COMPARE_MATCH_NO_WILD; /* Ok if w_many is last */
                }

                if (searchInPos == searchInEnd) {
                    return WILD_COMPARE_NO_MATCH;
                }

                if (((cmp = searchForWildcard.charAt(searchForPos)) == wildcardEscape) &&
                        ((searchForPos + 1) != searchForEnd)) {
                    cmp = searchForWildcard.charAt(++searchForPos);
                }

                searchForPos++;

                do {
                    while ((searchInPos != searchInEnd) &&
                            (Character.toUpperCase(searchIn.charAt(searchInPos)) != Character.toUpperCase(
                                cmp)))
                        searchInPos++;

                    if (searchInPos++ == searchInEnd) {
                        return WILD_COMPARE_NO_MATCH;
                    }

                    {
                        int tmp = wildCompare(searchIn, searchForWildcard);

                        if (tmp <= 0) {
                            return (tmp);
                        }
                    }
                } while ((searchInPos != searchInEnd) &&
                        (searchForWildcard.charAt(0) != wildcardMany));

                return WILD_COMPARE_NO_MATCH;
            }
        }

        return ((searchInPos != searchInEnd) ? WILD_COMPARE_MATCH_WITH_WILD
                                             : WILD_COMPARE_MATCH_NO_WILD);
    }

    public static long getLong(byte[] buf) throws NumberFormatException {
        int base = 10;

        int s = 0;

        /* Skip white space.  */
        while (Character.isWhitespace((char) buf[s]) && (s < buf.length)) {
            ++s;
        }

        if (s == buf.length) {
            throw new NumberFormatException(new String(buf));
        }

        /* Check for a sign.  */
        boolean negative = false;

        if ((char) buf[s] == '-') {
            negative = true;
            ++s;
        } else if ((char) buf[s] == '+') {
            ++s;
        }

        /* Save the pointer so we can check later if anything happened.  */
        int save = s;

        long cutoff = Long.MAX_VALUE / base;
        long cutlim = (int) (Long.MAX_VALUE % base);

        if (negative) {
            cutlim++;
        }

        boolean overflow = false;
        long i = 0;

        for (; s < buf.length; s++) {
            char c = (char) buf[s];

            if (Character.isDigit(c)) {
                c -= '0';
            } else if (Character.isLetter(c)) {
                c = (char) (Character.toUpperCase(c) - 'A' + 10);
            } else {
                break;
            }

            if (c >= base) {
                break;
            }

            /* Check for overflow.  */
            if ((i > cutoff) || ((i == cutoff) && (c > cutlim))) {
                overflow = true;
            } else {
                i *= base;
                i += c;
            }
        }

        if (s == save) {
            throw new NumberFormatException(new String(buf));
        }

        if (overflow) {
            throw new NumberFormatException(new String(buf));
        }

        /* Return the result of the appropriate sign.  */
        return (negative ? (-i) : i);
    }

    public static int getInt(byte[] buf) throws NumberFormatException {
        int base = 10;

        int s = 0;

        /* Skip white space.  */
        while (Character.isWhitespace((char) buf[s]) && (s < buf.length)) {
            ++s;
        }

        if (s == buf.length) {
            throw new NumberFormatException(new String(buf));
        }

        /* Check for a sign.  */
        boolean negative = false;

        if ((char) buf[s] == '-') {
            negative = true;
            ++s;
        } else if ((char) buf[s] == '+') {
            ++s;
        }

        /* Save the pointer so we can check later if anything happened.  */
        int save = s;

        int cutoff = Integer.MAX_VALUE / base;
        int cutlim = (Integer.MAX_VALUE % base);

        if (negative) {
            cutlim++;
        }

        boolean overflow = false;

        int i = 0;

        for (; s < buf.length; s++) {
            char c = (char) buf[s];

            if (Character.isDigit(c)) {
                c -= '0';
            } else if (Character.isLetter(c)) {
                c = (char) (Character.toUpperCase(c) - 'A' + 10);
            } else {
                break;
            }

            if (c >= base) {
                break;
            }

            /* Check for overflow.  */
            if ((i > cutoff) || ((i == cutoff) && (c > cutlim))) {
                overflow = true;
            } else {
                i *= base;
                i += c;
            }
        }

        if (s == save) {
            throw new NumberFormatException(new String(buf));
        }

        if (overflow) {
            throw new NumberFormatException(new String(buf));
        }

        /* Return the result of the appropriate sign.  */
        return (negative ? (-i) : i);
    }

    public static short getShort(byte[] buf) throws NumberFormatException {
        short base = 10;

        int s = 0;

        /* Skip white space.  */
        while (Character.isWhitespace((char) buf[s]) && (s < buf.length)) {
            ++s;
        }

        if (s == buf.length) {
            throw new NumberFormatException(new String(buf));
        }

        /* Check for a sign.  */
        boolean negative = false;

        if ((char) buf[s] == '-') {
            negative = true;
            ++s;
        } else if ((char) buf[s] == '+') {
            ++s;
        }

        /* Save the pointer so we can check later if anything happened.  */
        int save = s;

        short cutoff = (short) (Short.MAX_VALUE / base);
        short cutlim = (short) (Short.MAX_VALUE % base);

        if (negative) {
            cutlim++;
        }

        boolean overflow = false;
        short i = 0;

        for (; s < buf.length; s++) {
            char c = (char) buf[s];

            if (Character.isDigit(c)) {
                c -= '0';
            } else if (Character.isLetter(c)) {
                c = (char) (Character.toUpperCase(c) - 'A' + 10);
            } else {
                break;
            }

            if (c >= base) {
                break;
            }

            /* Check for overflow.  */
            if ((i > cutoff) || ((i == cutoff) && (c > cutlim))) {
                overflow = true;
            } else {
                i *= base;
                i += c;
            }
        }

        if (s == save) {
            throw new NumberFormatException(new String(buf));
        }

        if (overflow) {
            throw new NumberFormatException(new String(buf));
        }

        /* Return the result of the appropriate sign.  */
        return (negative ? (short) -i : (short) i);
    }

	/**
	 * Adds '+' to decimal numbers that are positive (MySQL doesn't understand
	 * them otherwise
	 *
	 * @param dString The value as a string
	 *
	 * @return String the string with a '+' added (if needed)
	 */
	public static final String fixDecimalExponent(String dString) {
	    int ePos = dString.indexOf("E"); //$NON-NLS-1$
	
	    if (ePos == -1) {
	        ePos = dString.indexOf("e"); //$NON-NLS-1$
	    }
	
	    if (ePos != -1) {
	        if (dString.length() > (ePos + 1)) {
	            char maybeMinusChar = dString.charAt(ePos + 1);
	
	            if (maybeMinusChar != '-' && maybeMinusChar != '+') {
	                StringBuffer buf = new StringBuffer(dString.length() + 1);
	                buf.append(dString.substring(0, ePos + 1));
	                buf.append('+');
	                buf.append(dString.substring(ePos + 1, dString.length()));
	                dString = buf.toString();
	            }
	        }
	    }
	
	    return dString;
	}

    /**
     * @param bytesToStrip
     * @param prefix
     * @param suffix
     * @return
     */
    public static byte[] stripEnclosure(byte[] source, String prefix, String suffix) {
        if (source.length >= prefix.length() + suffix.length() 
                && startsWith(source, prefix) 
                && endsWith(source, suffix)) {
            
            int totalToStrip = prefix.length() + suffix.length();
            int enclosedLength = source.length - totalToStrip;
            byte[] enclosed = new byte[enclosedLength];
            
            int startPos = prefix.length();
            int numToCopy = enclosed.length;
            System.arraycopy(source, startPos, enclosed, 0, numToCopy);
    
            return enclosed;
        }
        return source;
    }

    private static boolean startsWith(byte[] dataFrom, String chars) {
        for (int i = 0; i < chars.length(); i++) {
            if (dataFrom[i] != chars.charAt(i)){
                return false;
            }
        }
        return true;
    }

    private static boolean endsWith(byte[] dataFrom, String suffix){
        for (int i = 1; i <= suffix.length(); i++) {
            int dfOffset = dataFrom.length - i;
            int suffixOffset = suffix.length() - i;
            if (dataFrom[dfOffset] != suffix.charAt(suffixOffset)) {
                return false;
            }
        }
        return true;
    }

	/**
	 * Takes care of the fact that Sun changed the output of 
	 * BigDecimal.toString() between JDK-1.4 and JDK 5
	 * 
	 * @param decimal the big decimal to stringify
	 * 
	 * @return a string representation of 'decimal'
	 */
	public static String consistentToString(BigDecimal decimal) {
		if (decimal == null) {
			return null;
		}
		
		if (toPlainStringMethod != null) {
			try {
				return (String)toPlainStringMethod.invoke(decimal, null);
			} catch (InvocationTargetException invokeEx) {
				// that's okay, we fall-through to decimal.toString()
			} catch (IllegalAccessException accessEx) {
				// that's okay, we fall-through to decimal.toString()
			}
		}
		
		return decimal.toString();
	}
}