/*
 Copyright  2002-2004 MySQL AB, 2008 Sun Microsystems

 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.IOException;
import java.io.StringReader;
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 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;

	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()
		}
	}

	/**
	 * 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();
	}

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

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

		return outputBuf.toString();
	}

	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;
	}

	/**
	 * 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) {
		return firstNonWsCharUc(searchIn, 0);
	}
	
	public static char firstNonWsCharUc(String searchIn, int startAt) {
		if (searchIn == null) {
			return 0;
		}

		int length = searchIn.length();

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

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

		return 0;
	}

	public static char firstAlphaCharUc(String searchIn, int startAt) {
		if (searchIn == null) {
			return 0;
		}

		int length = searchIn.length();

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

			if (Character.isLetter(c)) {
				return Character.toUpperCase(c);
			}
		}

		return 0;
	}
	
	/**
	 * 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;
	}

	public static final byte[] getBytes(char[] c,
			SingleByteCharsetConverter converter, String encoding,
			String serverEncoding, boolean parserKnowsUnicode)
			throws SQLException {
		try {
			byte[] b = null;

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

				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 SQLError.createSQLException(Messages.getString("StringUtils.5") //$NON-NLS-1$
					+ encoding + Messages.getString("StringUtils.6"),
					SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
		}
	}

	public static final byte[] getBytes(char[] c,
			SingleByteCharsetConverter converter, String encoding,
			String serverEncoding, int offset, int length,
			boolean parserKnowsUnicode) throws SQLException {
		try {
			byte[] b = null;

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

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

				byte[] temp = s.getBytes(encoding);

				length = temp.length;
				
				b = new byte[length];
				System.arraycopy(temp, 0, 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 SQLError.createSQLException(Messages.getString("StringUtils.10") //$NON-NLS-1$
					+ encoding + Messages.getString("StringUtils.11"),
					SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
		}
	}

	public static final byte[] getBytes(char[] c, String encoding,
			String serverEncoding, boolean parserKnowsUnicode, 
			ConnectionImpl conn)
			throws SQLException {
		try {
			
			SingleByteCharsetConverter converter = null;
			
			if (conn != null) {
				converter = conn.getCharsetConverter(encoding);
			} else {
				converter = SingleByteCharsetConverter.getInstance(encoding, null);
			}

			return getBytes(c, converter, encoding, serverEncoding,
					parserKnowsUnicode);
		} catch (UnsupportedEncodingException uee) {
			throw SQLError.createSQLException(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 SQLError.createSQLException(Messages.getString("StringUtils.5") //$NON-NLS-1$
					+ encoding + Messages.getString("StringUtils.6"),
					SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
		}
	}

	public static final byte[] getBytesWrapped(String s, char beginWrap, char endWrap,
			SingleByteCharsetConverter converter, String encoding,
			String serverEncoding, boolean parserKnowsUnicode)
			throws SQLException {
		try {
			byte[] b = null;

			if (converter != null) {
				b = converter.toBytesWrapped(s, beginWrap, endWrap);
			} else if (encoding == null) {
				StringBuffer buf = new StringBuffer(s.length() + 2);
				buf.append(beginWrap);
				buf.append(s);
				buf.append(endWrap);
				
				b = buf.toString().getBytes();
			} else {
				StringBuffer buf = new StringBuffer(s.length() + 2);
				buf.append(beginWrap);
				buf.append(s);
				buf.append(endWrap);
				
				b = buf.toString().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 SQLError.createSQLException(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.substring(offset, offset + length).getBytes();

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

				byte[] temp = s.substring(offset, offset + length)
					.getBytes(encoding);

				length = temp.length;
				
				b = new byte[length];
				System.arraycopy(temp, 0, 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 SQLError.createSQLException(Messages.getString("StringUtils.10") //$NON-NLS-1$
					+ encoding + Messages.getString("StringUtils.11"),
					SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
		}
	}

	/**
	 * 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, 
			ConnectionImpl conn)
			throws SQLException {
		try {
			SingleByteCharsetConverter converter = null;
			
			if (conn != null) {
				converter = conn.getCharsetConverter(encoding);
			} else {
				converter = SingleByteCharsetConverter.getInstance(encoding, null);
			}

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

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

		int s = offset;

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

		if (s == endPos) {
			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 < endPos; 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 {
		return getInt(buf, 0, buf.length);
	}

	public static long getLong(byte[] buf) throws NumberFormatException {
		return getLong(buf, 0, buf.length);
	}
	
	public static long getLong(byte[] buf, int offset, int endpos) throws NumberFormatException {
		int base = 10;

		int s = offset;

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

		if (s == endpos) {
			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 < endpos; 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);
	}

	public final static int indexOfIgnoreCase(int startingPosition,
			String searchIn, String searchFor) {
		if ((searchIn == null) || (searchFor == null)
				|| startingPosition > searchIn.length()) {
			return -1;
		}

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

		int i = startingPosition;

		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
		}
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @param searchIn
	 *            DOCUMENT ME!
	 * @param searchFor
	 *            DOCUMENT ME!
	 * 
	 * @return DOCUMENT ME!
	 */
	public final static int indexOfIgnoreCase(String searchIn, String searchFor) {
		return indexOfIgnoreCase(0, searchIn, searchFor);
	}

	public static int indexOfIgnoreCaseRespectMarker(int startAt, String src,
			String target, String marker, String markerCloses,
			boolean allowBackslashEscapes) {
		char contextMarker = Character.MIN_VALUE;
		boolean escaped = false;
		int markerTypeFound = 0;
		int srcLength = src.length();
		int ind = 0;

		for (int i = startAt; i < srcLength; i++) {
			char c = src.charAt(i);

			if (allowBackslashEscapes && c == '\\') {
				escaped = !escaped;
			} else if (c == markerCloses.charAt(markerTypeFound) && !escaped) {
				contextMarker = Character.MIN_VALUE;
			} else if ((ind = marker.indexOf(c)) != -1 && !escaped
					&& contextMarker == Character.MIN_VALUE) {
				markerTypeFound = ind;
				contextMarker = c;
			} else if (c == target.charAt(0) && !escaped
					&& contextMarker == Character.MIN_VALUE) {
				if (indexOfIgnoreCase(i, src, target) != -1)
					return i;
			}
		}

		return -1;

	}

	public static int indexOfIgnoreCaseRespectQuotes(int startAt, String src,
			String target, char quoteChar, boolean allowBackslashEscapes) {
		char contextMarker = Character.MIN_VALUE;
		boolean escaped = false;

		int srcLength = src.length();

		for (int i = startAt; i < srcLength; i++) {
			char c = src.charAt(i);

			if (allowBackslashEscapes && c == '\\') {
				escaped = !escaped;
			} else if (c == contextMarker && !escaped) {
				contextMarker = Character.MIN_VALUE;
			} else if (c == quoteChar && !escaped
					&& contextMarker == Character.MIN_VALUE) {
				contextMarker = c;
			// This test looks complex, but remember that in certain locales, upper case
			// of two different codepoints coverts to same codepoint, and vice-versa.
			} else if ((Character.toUpperCase(c) == Character.toUpperCase(target.charAt(0)) ||
					Character.toLowerCase(c) == Character.toLowerCase(target.charAt(0))) && !escaped
					&& contextMarker == Character.MIN_VALUE) {
				if (startsWithIgnoreCase(src, i, target))
					return i;
			}
		}

		return -1;

	}

	/**
	 * 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;
	}

	/**
	 * 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 delimiter
	 * 
	 * @throws IllegalArgumentException
	 *             DOCUMENT ME!
	 */
	public static final List split(String stringToSplit, String delimiter,
			String markers, String markerCloses, boolean trim) {
		if (stringToSplit == null) {
			return new ArrayList();
		}

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

		int delimPos = 0;
		int currentPos = 0;

		List splitTokens = new ArrayList();

		while ((delimPos = indexOfIgnoreCaseRespectMarker(currentPos,
				stringToSplit, delimiter, markers, markerCloses, false)) != -1) {
			String token = stringToSplit.substring(currentPos, delimPos);

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

			splitTokens.add(token);
			currentPos = delimPos + 1;
		}

		if (currentPos < stringToSplit.length()) {
			String token = stringToSplit.substring(currentPos);

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

			splitTokens.add(token);
		}

		return splitTokens;
	}

	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;
	}

	/**
	 * 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, startAt, searchFor, 0, searchFor
				.length());
	}

	/**
	 * 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 sting 'searchIn' contains the string
	 * 'searchFor', disregarding case,leading whitespace and non-alphanumeric
	 * characters.
	 * 
	 * @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 startsWithIgnoreCaseAndNonAlphaNumeric(
			String searchIn, String searchFor) {
		if (searchIn == null) {
			return searchFor == null;
		}

		int beginPos = 0;

		int inLength = searchIn.length();

		for (beginPos = 0; beginPos < inLength; beginPos++) {
			char c = searchIn.charAt(beginPos);

			if (Character.isLetterOrDigit(c)) {
				break;
			}
		}

		return startsWithIgnoreCase(searchIn, beginPos, searchFor);
	}

	/**
	 * Determines whether or not the sting 'searchIn' contains the string
	 * 'searchFor', disregarding 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) {
		return startsWithIgnoreCaseAndWs(searchIn, searchFor, 0);
	}
	
	/**
	 * Determines whether or not the sting 'searchIn' contains the string
	 * 'searchFor', disregarding case and leading whitespace
	 * 
	 * @param searchIn
	 *            the string to search in
	 * @param searchFor
	 *            the string to search for
	 * @param beginPos
	 *            where to start searching
	 * 
	 * @return true if the string starts with 'searchFor' ignoring whitespace
	 */
	
	public static boolean startsWithIgnoreCaseAndWs(String searchIn,
			String searchFor, int beginPos) {
		if (searchIn == null) {
			return searchFor == null;
		}

		int inLength = searchIn.length();

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

		return startsWithIgnoreCase(searchIn, beginPos, searchFor);
	}

	/**
	 * @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;
	}

	/**
	 * 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);
	}

	/**
	 * 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);
	}
	
	static byte[] s2b(String s, ConnectionImpl conn) throws SQLException {
		if (s == null) {
			return null;
		}
		
		if ((conn != null) && conn.getUseUnicode()) {
			try {
				String encoding = conn.getEncoding();

				if (encoding == null) {
					return s.getBytes();
				}

				SingleByteCharsetConverter converter = conn
						.getCharsetConverter(encoding);

				if (converter != null) {
					return converter.toBytes(s);
				}

				return s.getBytes(encoding);
			} catch (java.io.UnsupportedEncodingException E) {
				return s.getBytes();
			}
		}

		return s.getBytes();
	}
	
	public static int lastIndexOf(byte[] s, char c) {
		if (s == null) {
			return -1;
		}
		
		for (int i = s.length - 1; i >= 0; i--) {
			if (s[i] == c) {
				return i;
			}
		}
		
		return -1;
	}

	public static int indexOf(byte[] s, char c) {
		if (s == null) {
			return -1;
		}
		
		int length = s.length;
		
		for (int i = 0; i < length; i++) {
			if (s[i] == c) {
				return i;
			}
		}
		
		return -1;
	}
	
	public static boolean isNullOrEmpty(String toTest) {
		return (toTest == null || toTest.length() == 0);
	}
	
	/**
	 * Returns the given string, with comments removed
	 * 
	 * @param src
	 *            the source string
	 * @param stringOpens
	 *            characters which delimit the "open" of a string
	 * @param stringCloses
	 *            characters which delimit the "close" of a string, in
	 *            counterpart order to <code>stringOpens</code>
	 * @param slashStarComments
	 *            strip slash-star type "C" style comments
	 * @param slashSlashComments
	 *            strip slash-slash C++ style comments to end-of-line
	 * @param hashComments
	 *            strip #-style comments to end-of-line
	 * @param dashDashComments
	 *            strip "--" style comments to end-of-line
	 * @return the input string with all comment-delimited data removed
	 */
	public static String stripComments(String src, String stringOpens,
			String stringCloses, boolean slashStarComments,
			boolean slashSlashComments, boolean hashComments,
			boolean dashDashComments) {
		if (src == null) {
			return null;
		}

		StringBuffer buf = new StringBuffer(src.length());

		// It's just more natural to deal with this as a stream
		// when parsing..This code is currently only called when
		// parsing the kind of metadata that developers are strongly
		// recommended to cache anyways, so we're not worried
		// about the _1_ extra object allocation if it cleans
		// up the code

		StringReader sourceReader = new StringReader(src);

		int contextMarker = Character.MIN_VALUE;
		boolean escaped = false;
		int markerTypeFound = -1;

		int ind = 0;

		int currentChar = 0;

		try {
			while ((currentChar = sourceReader.read()) != -1) {

				if (false && currentChar == '\\') {
					escaped = !escaped;
				} else if (markerTypeFound != -1 && currentChar == stringCloses.charAt(markerTypeFound)
						&& !escaped) {
					contextMarker = Character.MIN_VALUE;
					markerTypeFound = -1;
				} else if ((ind = stringOpens.indexOf(currentChar)) != -1
						&& !escaped && contextMarker == Character.MIN_VALUE) {
					markerTypeFound = ind;
					contextMarker = currentChar;
				}

				if (contextMarker == Character.MIN_VALUE && currentChar == '/'
						&& (slashSlashComments || slashStarComments)) {
					currentChar = sourceReader.read();
					if (currentChar == '*' && slashStarComments) {
						int prevChar = 0;
						while ((currentChar = sourceReader.read()) != '/'
								|| prevChar != '*') {
							if (currentChar == '\r') {

								currentChar = sourceReader.read();
								if (currentChar == '\n') {
									currentChar = sourceReader.read();
								}
							} else {
								if (currentChar == '\n') {

									currentChar = sourceReader.read();
								}
							}
							if (currentChar < 0)
								break;
							prevChar = currentChar;
						}
						continue;
					} else if (currentChar == '/' && slashSlashComments) {
						while ((currentChar = sourceReader.read()) != '\n'
								&& currentChar != '\r' && currentChar >= 0)
							;
					}
				} else if (contextMarker == Character.MIN_VALUE
						&& currentChar == '#' && hashComments) {
					// Slurp up everything until the newline
					while ((currentChar = sourceReader.read()) != '\n'
							&& currentChar != '\r' && currentChar >= 0)
						;
				} else if (contextMarker == Character.MIN_VALUE
						&& currentChar == '-' && dashDashComments) {
					currentChar = sourceReader.read();

					if (currentChar == -1 || currentChar != '-') {
						buf.append('-');

						if (currentChar != -1) {
							buf.append(currentChar);
						}

						continue;
					}

					// Slurp up everything until the newline

					while ((currentChar = sourceReader.read()) != '\n'
							&& currentChar != '\r' && currentChar >= 0)
						;
				}

				if (currentChar != -1) {
					buf.append((char) currentChar);
				}
			}
		} catch (IOException ioEx) {
			// we'll never see this from a StringReader
		}

		return buf.toString();
	}
	
	public static final boolean isEmptyOrWhitespaceOnly(String str) {
		if (str == null || str.length() == 0) {
			return true;
		}
		
		int length = str.length();
		
		for (int i = 0; i < length; i++) {
			if (!Character.isWhitespace(str.charAt(i))) {
				return false;
			}
		}
		
		return true;
	}
}
