src/java/org/apache/poi/util/LittleEndian.java - poi - Git at Google

 /*
  *  ====================================================================
  *  The Apache Software License, Version 1.1
  *
  *  Copyright (c) 2003 The Apache Software Foundation.  All rights
  *  reserved.
  *
  *  Redistribution and use in source and binary forms, with or without
  *  modification, are permitted provided that the following conditions
  *  are met:
  *
  *  1. Redistributions of source code must retain the above copyright
  *  notice, this list of conditions and the following disclaimer.
  *
  *  2. Redistributions in binary form must reproduce the above copyright
  *  notice, this list of conditions and the following disclaimer in
  *  the documentation and/or other materials provided with the
  *  distribution.
  *
  *  3. The end-user documentation included with the redistribution,
  *  if any, must include the following acknowledgment:
  *  "This product includes software developed by the
  *  Apache Software Foundation (http://www.apache.org/)."
  *  Alternately, this acknowledgment may appear in the software itself,
  *  if and wherever such third-party acknowledgments normally appear.
  *
  *  4. The names "Apache" and "Apache Software Foundation" and
  *  "Apache POI" must not be used to endorse or promote products
  *  derived from this software without prior written permission. For
  *  written permission, please contact apache@apache.org.
  *
  *  5. Products derived from this software may not be called "Apache",
  *  "Apache POI", nor may "Apache" appear in their name, without
  *  prior written permission of the Apache Software Foundation.
  *
  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  *  DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  *  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  *  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  *  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  *  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  *  SUCH DAMAGE.
  *  ====================================================================
  *
  *  This software consists of voluntary contributions made by many
  *  individuals on behalf of the Apache Software Foundation.  For more
  *  information on the Apache Software Foundation, please see
  *  <http://www.apache.org/>.
  */
 package org.apache.poi.util;

 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Arrays;

 /**
  *  a utility class for handling little-endian numbers, which the 80x86 world is
  *  replete with. The methods are all static, and input/output is from/to byte
  *  arrays, or from InputStreams.
  *
  *@author     Marc Johnson (mjohnson at apache dot org)
  *@author     Andrew Oliver (acoliver at apache dot org)
  */

 public class LittleEndian
          implements LittleEndianConsts {

     // all methods are static, so an accessible constructor makes no
     // sense
     /**
      *  Constructor for the LittleEndian object
      */
     private LittleEndian() { }


     /**
      *  get a short value from a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@return         the short (16-bit) value
      */

     public static short getShort(final byte[] data, final int offset) {
         return (short) getNumber(data, offset, SHORT_SIZE);
     }


     /**
      *  get an unsigned short value from a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@return         the unsigned short (16-bit) value in an integer
      */
     public static int getUShort(final byte[] data, final int offset) {
         short num = (short) getNumber(data, offset, SHORT_SIZE);
         int retNum;
         if (num < 0) {
             retNum = ((int) Short.MAX_VALUE + 1) * 2 + (int) num;
         } else {
             retNum = (int) num;
         }
         return retNum;
     }


     /**
      *  get a short array from a byte array.
      *
      *@param  data    Description of the Parameter
      *@param  offset  Description of the Parameter
      *@param  size    Description of the Parameter
      *@return         The simpleShortArray value
      */
     public static short[] getSimpleShortArray(final byte[] data, final int offset, final int size) {
         short[] results = new short[size];
         for (int i = 0; i < size; i++) {
             results[i] = getShort(data, offset + 2 + (i * 2));
         }
         return results;
     }


     /**
      *  get a short array from a byte array. The short array is assumed to start
      *  with a word describing the length of the array.
      *
      *@param  data    Description of the Parameter
      *@param  offset  Description of the Parameter
      *@return         The shortArray value
      */
     public static short[] getShortArray(final byte[] data, final int offset) {
         int size = (short) getNumber(data, offset, SHORT_SIZE);
         short[] results = getSimpleShortArray(data, offset, size);
         return results;
     }


     /**
      *  get a short value from the beginning of a byte array
      *
      *@param  data  the byte array
      *@return       the short (16-bit) value
      */

     public static short getShort(final byte[] data) {
         return getShort(data, 0);
     }


     /**
      *  get an unsigned short value from the beginning of a byte array
      *
      *@param  data  the byte array
      *@return       the unsigned short (16-bit) value in an int
      */
     public static int getUShort(final byte[] data) {
         return getUShort(data, 0);
     }


     /**
      *  get an int value from a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@return         the int (32-bit) value
      */

     public static int getInt(final byte[] data, final int offset) {
         return (int) getNumber(data, offset, INT_SIZE);
     }


     /**
      *  get an int value from the beginning of a byte array
      *
      *@param  data  the byte array
      *@return       the int (32-bit) value
      */

     public static int getInt(final byte[] data) {
         return getInt(data, 0);
     }


     /**
      *  get an unsigned int value from a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@return         the unsigned int (32-bit) value in a long
      */
     public static long getUInt(final byte[] data, final int offset) {
         int num = (int) getNumber(data, offset, INT_SIZE);
         long retNum;
         if (num < 0) {
             retNum = ((long) Integer.MAX_VALUE + 1) * 2 + (long) num;
         } else {
             retNum = (int) num;
         }
         return retNum;
     }

     /**
      *  get an unsigned int value from a byte array
      *
      *@param  data    the byte array
      *@return         the unsigned int (32-bit) value in a long
      */
     public static long getUInt(final byte[] data) {
 	return getUInt(data,0);
     }

     /**
      *  get a long value from a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@return         the long (64-bit) value
      */

     public static long getLong(final byte[] data, final int offset) {
         return getNumber(data, offset, LONG_SIZE);
     }


     /**
      *  get a long value from the beginning of a byte array
      *
      *@param  data  the byte array
      *@return       the long (64-bit) value
      */

     public static long getLong(final byte[] data) {
         return getLong(data, 0);
     }


     /**
      *  get a double value from a byte array, reads it in little endian format
      *  then converts the resulting revolting IEEE 754 (curse them) floating
      *  point number to a happy java double
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@return         the double (64-bit) value
      */

     public static double getDouble(final byte[] data, final int offset) {
         return Double.longBitsToDouble(getNumber(data, offset, DOUBLE_SIZE));
     }


     /**
      *  get a double value from the beginning of a byte array
      *
      *@param  data  the byte array
      *@return       the double (64-bit) value
      */

     public static double getDouble(final byte[] data) {
         return getDouble(data, 0);
     }


     /**
      *  put a short value into a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@param  value   the short (16-bit) value
      */
     public static void putShort(final byte[] data, final int offset,
             final short value) {
         putNumber(data, offset, value, SHORT_SIZE);
     }


     /**
      *  put a array of shorts into a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@param  value   the short array
      */
     public static void putShortArray(final byte[] data, final int offset, final short[] value) {
         putNumber(data, offset, value.length, SHORT_SIZE);
         for (int i = 0; i < value.length; i++) {
             putNumber(data, offset + 2 + (i * 2), value[i], SHORT_SIZE);
         }
     }

     /**
      * put an unsigned short value into a byte array
      *
      * @param data the byte array
      * @param offset a starting offset into the byte array
      * @param value the short (16-bit) value
      *
      * @exception ArrayIndexOutOfBoundsException may be thrown
      */
     public static void putUShort(final byte[] data, final int offset,
                                 final int value)
     {
         putNumber(data, offset, value, SHORT_SIZE);
     }

     /**
      *  put a short value into beginning of a byte array
      *
      *@param  data   the byte array
      *@param  value  the short (16-bit) value
      */

     public static void putShort(final byte[] data, final short value) {
         putShort(data, 0, value);
     }


     /**
      *  put an int value into a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@param  value   the int (32-bit) value
      */

     public static void putInt(final byte[] data, final int offset,
             final int value) {
         putNumber(data, offset, value, INT_SIZE);
     }


     /**
      *  put an int value into beginning of a byte array
      *
      *@param  data   the byte array
      *@param  value  the int (32-bit) value
      */

     public static void putInt(final byte[] data, final int value) {
         putInt(data, 0, value);
     }


     /**
      *  put a long value into a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@param  value   the long (64-bit) value
      */

     public static void putLong(final byte[] data, final int offset,
             final long value) {
         putNumber(data, offset, value, LONG_SIZE);
     }


     /**
      *  put a long value into beginning of a byte array
      *
      *@param  data   the byte array
      *@param  value  the long (64-bit) value
      */

     public static void putLong(final byte[] data, final long value) {
         putLong(data, 0, value);
     }


     /**
      *  put a double value into a byte array
      *
      *@param  data    the byte array
      *@param  offset  a starting offset into the byte array
      *@param  value   the double (64-bit) value
      */

     public static void putDouble(final byte[] data, final int offset,
             final double value) {
         // Excel likes NaN to be a specific value.
         if (Double.isNaN(value))
             putNumber(data, offset, -276939487313920L, DOUBLE_SIZE);
         else
             putNumber(data, offset, Double.doubleToLongBits(value), DOUBLE_SIZE);
     }


     /**
      *  put a double value into beginning of a byte array
      *
      *@param  data   the byte array
      *@param  value  the double (64-bit) value
      */

     public static void putDouble(final byte[] data, final double value) {
         putDouble(data, 0, value);
     }


     /**
      *  Exception to handle buffer underruns
      *
      *@author     Marc Johnson (mjohnson at apache dot org)
      */

     public static class BufferUnderrunException
              extends IOException {

         /**
          *  simple constructor
          */

         BufferUnderrunException() {
             super("buffer underrun");
         }
     }


     /**
      *  get a short value from an InputStream
      *
      *@param  stream                       the InputStream from which the short
      *      is to be read
      *@return                              the short (16-bit) value
      *@exception  IOException              will be propagated back to the caller
      *@exception  BufferUnderrunException  if the stream cannot provide enough
      *      bytes
      */

     public static short readShort(final InputStream stream)
              throws IOException, BufferUnderrunException {
         return getShort(readFromStream(stream, SHORT_SIZE));
     }


     /**
      *  get an int value from an InputStream
      *
      *@param  stream                       the InputStream from which the int is
      *      to be read
      *@return                              the int (32-bit) value
      *@exception  IOException              will be propagated back to the caller
      *@exception  BufferUnderrunException  if the stream cannot provide enough
      *      bytes
      */

     public static int readInt(final InputStream stream)
              throws IOException, BufferUnderrunException {
         return getInt(readFromStream(stream, INT_SIZE));
     }


     /**
      *  get a long value from an InputStream
      *
      *@param  stream                       the InputStream from which the long
      *      is to be read
      *@return                              the long (64-bit) value
      *@exception  IOException              will be propagated back to the caller
      *@exception  BufferUnderrunException  if the stream cannot provide enough
      *      bytes
      */

     public static long readLong(final InputStream stream)
              throws IOException, BufferUnderrunException {
         return getLong(readFromStream(stream, LONG_SIZE));
     }

     /**
      *  Read the appropriate number of bytes from the stream and return them to
      *  the caller. <p>
      *
      *  However, for the purposes of the POI project, this risk is deemed
      *  negligible. It is, however, so noted.
      *
      *@param  stream                       the InputStream we're reading from
      *@param  size                         the number of bytes to read; in
      *      99.99% of cases, this will be SHORT_SIZE, INT_SIZE, or LONG_SIZE --
      *      but it doesn't have to be.
      *@return                              the byte array containing the
      *      required number of bytes. The array will contain all zero's on end
      *      of stream
      *@exception  IOException              will be propagated back to the caller
      *@exception  BufferUnderrunException  if the stream cannot provide enough
      *      bytes
      */

     public static byte[] readFromStream(final InputStream stream,
             final int size)
              throws IOException, BufferUnderrunException {
         byte[] buffer = new byte[size];

         int count = stream.read(buffer);

         if (count == -1) {

             // return a zero-filled buffer
             Arrays.fill(buffer, (byte) 0);
         } else if (count != size) {
             throw new BufferUnderrunException();
         }
         return buffer;
     }


     /**
      *  Gets the number attribute of the LittleEndian class
      *
      *@param  data    Description of the Parameter
      *@param  offset  Description of the Parameter
      *@param  size    Description of the Parameter
      *@return         The number value
      */
     private static long getNumber(final byte[] data, final int offset,
             final int size) {
         long result = 0;

         for (int j = offset + size - 1; j >= offset; j--) {
             result <<= 8;
             result |= 0xff & data[j];
         }
         return result;
     }


     /**
      *  Description of the Method
      *
      *@param  data    Description of the Parameter
      *@param  offset  Description of the Parameter
      *@param  value   Description of the Parameter
      *@param  size    Description of the Parameter
      */
     private static void putNumber(final byte[] data, final int offset,
             final long value, final int size) {
         int limit = size + offset;
         long v = value;

         for (int j = offset; j < limit; j++) {
             data[j] = (byte) (v & 0xFF);
             v >>= 8;
         }
     }


     /**
      *  Convert an 'unsigned' byte to an integer. ie, don't carry across the
      *  sign.
      *
      *@param  b  Description of the Parameter
      *@return    Description of the Return Value
      */
     public static int ubyteToInt(byte b) {
         return ((b & 0x80) == 0 ? (int) b : (int) (b & (byte) 0x7f) + 0x80);
     }


     /**
      *  get the unsigned value of a byte.
      *
      *@param  data    the byte array.
      *@param  offset  a starting offset into the byte array.
      *@return         the unsigned value of the byte as a 32 bit integer
      */
     public static int getUnsignedByte(final byte[] data, final int offset) {
         return (int) getNumber(data, offset, BYTE_SIZE);
     }


     /**
      *  get the unsigned value of a byte.
      *
      *@param  data  the byte array
      *@return       the unsigned value of the byte as a 32 bit integer
      */
     public static int getUnsignedByte(final byte[] data) {
         return getUnsignedByte(data, 0);
     }


     /**
      *  Copy a portion of a byte array
      *
      *@param  data                        the original byte array
      *@param  offset                      Where to start copying from.
      *@param  size                        Number of bytes to copy.
      *@return                             The byteArray value
      *@throws  IndexOutOfBoundsException  - if copying would cause access of
      *      data outside array bounds.
      */
     public static byte[] getByteArray(final byte[] data, int offset, int size) {
         byte[] copy = new byte[size];
         System.arraycopy(data, offset, copy, 0, size);

         return copy;
     }


 }
	/*
	* ====================================================================
	* The Apache Software License, Version 1.1
	*
	* Copyright (c) 2003 The Apache Software Foundation. All rights
	* reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	*
	* 3. The end-user documentation included with the redistribution,
	* if any, must include the following acknowledgment:
	* "This product includes software developed by the
	* Apache Software Foundation (http://www.apache.org/)."
	* Alternately, this acknowledgment may appear in the software itself,
	* if and wherever such third-party acknowledgments normally appear.
	*
	* 4. The names "Apache" and "Apache Software Foundation" and
	* "Apache POI" must not be used to endorse or promote products
	* derived from this software without prior written permission. For
	* written permission, please contact apache@apache.org.
	*
	* 5. Products derived from this software may not be called "Apache",
	* "Apache POI", nor may "Apache" appear in their name, without
	* prior written permission of the Apache Software Foundation.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	* ====================================================================
	*
	* This software consists of voluntary contributions made by many
	* individuals on behalf of the Apache Software Foundation. For more
	* information on the Apache Software Foundation, please see
	* <http://www.apache.org/>.
	*/
	package org.apache.poi.util;

	import java.io.IOException;
	import java.io.InputStream;
	import java.util.Arrays;

	/**
	* a utility class for handling little-endian numbers, which the 80x86 world is
	* replete with. The methods are all static, and input/output is from/to byte
	* arrays, or from InputStreams.
	*
	*@author Marc Johnson (mjohnson at apache dot org)
	*@author Andrew Oliver (acoliver at apache dot org)
	*/

	public class LittleEndian
	implements LittleEndianConsts {

	// all methods are static, so an accessible constructor makes no
	// sense
	/**
	* Constructor for the LittleEndian object
	*/
	private LittleEndian() { }


	/**
	* get a short value from a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@return the short (16-bit) value
	*/

	public static short getShort(final byte[] data, final int offset) {
	return (short) getNumber(data, offset, SHORT_SIZE);
	}


	/**
	* get an unsigned short value from a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@return the unsigned short (16-bit) value in an integer
	*/
	public static int getUShort(final byte[] data, final int offset) {
	short num = (short) getNumber(data, offset, SHORT_SIZE);
	int retNum;
	if (num < 0) {
	retNum = ((int) Short.MAX_VALUE + 1) * 2 + (int) num;
	} else {
	retNum = (int) num;
	}
	return retNum;
	}


	/**
	* get a short array from a byte array.
	*
	*@param data Description of the Parameter
	*@param offset Description of the Parameter
	*@param size Description of the Parameter
	*@return The simpleShortArray value
	*/
	public static short[] getSimpleShortArray(final byte[] data, final int offset, final int size) {
	short[] results = new short[size];
	for (int i = 0; i < size; i++) {
	results[i] = getShort(data, offset + 2 + (i * 2));
	}
	return results;
	}


	/**
	* get a short array from a byte array. The short array is assumed to start
	* with a word describing the length of the array.
	*
	*@param data Description of the Parameter
	*@param offset Description of the Parameter
	*@return The shortArray value
	*/
	public static short[] getShortArray(final byte[] data, final int offset) {
	int size = (short) getNumber(data, offset, SHORT_SIZE);
	short[] results = getSimpleShortArray(data, offset, size);
	return results;
	}


	/**
	* get a short value from the beginning of a byte array
	*
	*@param data the byte array
	*@return the short (16-bit) value
	*/

	public static short getShort(final byte[] data) {
	return getShort(data, 0);
	}


	/**
	* get an unsigned short value from the beginning of a byte array
	*
	*@param data the byte array
	*@return the unsigned short (16-bit) value in an int
	*/
	public static int getUShort(final byte[] data) {
	return getUShort(data, 0);
	}


	/**
	* get an int value from a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@return the int (32-bit) value
	*/

	public static int getInt(final byte[] data, final int offset) {
	return (int) getNumber(data, offset, INT_SIZE);
	}


	/**
	* get an int value from the beginning of a byte array
	*
	*@param data the byte array
	*@return the int (32-bit) value
	*/

	public static int getInt(final byte[] data) {
	return getInt(data, 0);
	}


	/**
	* get an unsigned int value from a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@return the unsigned int (32-bit) value in a long
	*/
	public static long getUInt(final byte[] data, final int offset) {
	int num = (int) getNumber(data, offset, INT_SIZE);
	long retNum;
	if (num < 0) {
	retNum = ((long) Integer.MAX_VALUE + 1) * 2 + (long) num;
	} else {
	retNum = (int) num;
	}
	return retNum;
	}

	/**
	* get an unsigned int value from a byte array
	*
	*@param data the byte array
	*@return the unsigned int (32-bit) value in a long
	*/
	public static long getUInt(final byte[] data) {
	return getUInt(data,0);
	}

	/**
	* get a long value from a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@return the long (64-bit) value
	*/

	public static long getLong(final byte[] data, final int offset) {
	return getNumber(data, offset, LONG_SIZE);
	}


	/**
	* get a long value from the beginning of a byte array
	*
	*@param data the byte array
	*@return the long (64-bit) value
	*/

	public static long getLong(final byte[] data) {
	return getLong(data, 0);
	}


	/**
	* get a double value from a byte array, reads it in little endian format
	* then converts the resulting revolting IEEE 754 (curse them) floating
	* point number to a happy java double
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@return the double (64-bit) value
	*/

	public static double getDouble(final byte[] data, final int offset) {
	return Double.longBitsToDouble(getNumber(data, offset, DOUBLE_SIZE));
	}


	/**
	* get a double value from the beginning of a byte array
	*
	*@param data the byte array
	*@return the double (64-bit) value
	*/

	public static double getDouble(final byte[] data) {
	return getDouble(data, 0);
	}


	/**
	* put a short value into a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@param value the short (16-bit) value
	*/
	public static void putShort(final byte[] data, final int offset,
	final short value) {
	putNumber(data, offset, value, SHORT_SIZE);
	}


	/**
	* put a array of shorts into a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@param value the short array
	*/
	public static void putShortArray(final byte[] data, final int offset, final short[] value) {
	putNumber(data, offset, value.length, SHORT_SIZE);
	for (int i = 0; i < value.length; i++) {
	putNumber(data, offset + 2 + (i * 2), value[i], SHORT_SIZE);
	}
	}

	/**
	* put an unsigned short value into a byte array
	*
	* @param data the byte array
	* @param offset a starting offset into the byte array
	* @param value the short (16-bit) value
	*
	* @exception ArrayIndexOutOfBoundsException may be thrown
	*/
	public static void putUShort(final byte[] data, final int offset,
	final int value)
	{
	putNumber(data, offset, value, SHORT_SIZE);
	}

	/**
	* put a short value into beginning of a byte array
	*
	*@param data the byte array
	*@param value the short (16-bit) value
	*/

	public static void putShort(final byte[] data, final short value) {
	putShort(data, 0, value);
	}


	/**
	* put an int value into a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@param value the int (32-bit) value
	*/

	public static void putInt(final byte[] data, final int offset,
	final int value) {
	putNumber(data, offset, value, INT_SIZE);
	}


	/**
	* put an int value into beginning of a byte array
	*
	*@param data the byte array
	*@param value the int (32-bit) value
	*/

	public static void putInt(final byte[] data, final int value) {
	putInt(data, 0, value);
	}


	/**
	* put a long value into a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@param value the long (64-bit) value
	*/

	public static void putLong(final byte[] data, final int offset,
	final long value) {
	putNumber(data, offset, value, LONG_SIZE);
	}


	/**
	* put a long value into beginning of a byte array
	*
	*@param data the byte array
	*@param value the long (64-bit) value
	*/

	public static void putLong(final byte[] data, final long value) {
	putLong(data, 0, value);
	}


	/**
	* put a double value into a byte array
	*
	*@param data the byte array
	*@param offset a starting offset into the byte array
	*@param value the double (64-bit) value
	*/

	public static void putDouble(final byte[] data, final int offset,
	final double value) {
	// Excel likes NaN to be a specific value.
	if (Double.isNaN(value))
	putNumber(data, offset, -276939487313920L, DOUBLE_SIZE);
	else
	putNumber(data, offset, Double.doubleToLongBits(value), DOUBLE_SIZE);
	}


	/**
	* put a double value into beginning of a byte array
	*
	*@param data the byte array
	*@param value the double (64-bit) value
	*/

	public static void putDouble(final byte[] data, final double value) {
	putDouble(data, 0, value);
	}


	/**
	* Exception to handle buffer underruns
	*
	*@author Marc Johnson (mjohnson at apache dot org)
	*/

	public static class BufferUnderrunException
	extends IOException {

	/**
	* simple constructor
	*/

	BufferUnderrunException() {
	super("buffer underrun");
	}
	}


	/**
	* get a short value from an InputStream
	*
	*@param stream the InputStream from which the short
	* is to be read
	*@return the short (16-bit) value
	*@exception IOException will be propagated back to the caller
	*@exception BufferUnderrunException if the stream cannot provide enough
	* bytes
	*/

	public static short readShort(final InputStream stream)
	throws IOException, BufferUnderrunException {
	return getShort(readFromStream(stream, SHORT_SIZE));
	}


	/**
	* get an int value from an InputStream
	*
	*@param stream the InputStream from which the int is
	* to be read
	*@return the int (32-bit) value
	*@exception IOException will be propagated back to the caller
	*@exception BufferUnderrunException if the stream cannot provide enough
	* bytes
	*/

	public static int readInt(final InputStream stream)
	throws IOException, BufferUnderrunException {
	return getInt(readFromStream(stream, INT_SIZE));
	}


	/**
	* get a long value from an InputStream
	*
	*@param stream the InputStream from which the long
	* is to be read
	*@return the long (64-bit) value
	*@exception IOException will be propagated back to the caller
	*@exception BufferUnderrunException if the stream cannot provide enough
	* bytes
	*/

	public static long readLong(final InputStream stream)
	throws IOException, BufferUnderrunException {
	return getLong(readFromStream(stream, LONG_SIZE));
	}

	/**
	* Read the appropriate number of bytes from the stream and return them to
	* the caller. <p>
	*
	* However, for the purposes of the POI project, this risk is deemed
	* negligible. It is, however, so noted.
	*
	*@param stream the InputStream we're reading from
	*@param size the number of bytes to read; in
	* 99.99% of cases, this will be SHORT_SIZE, INT_SIZE, or LONG_SIZE --
	* but it doesn't have to be.
	*@return the byte array containing the
	* required number of bytes. The array will contain all zero's on end
	* of stream
	*@exception IOException will be propagated back to the caller
	*@exception BufferUnderrunException if the stream cannot provide enough
	* bytes
	*/

	public static byte[] readFromStream(final InputStream stream,
	final int size)
	throws IOException, BufferUnderrunException {
	byte[] buffer = new byte[size];

	int count = stream.read(buffer);

	if (count == -1) {

	// return a zero-filled buffer
	Arrays.fill(buffer, (byte) 0);
	} else if (count != size) {
	throw new BufferUnderrunException();
	}
	return buffer;
	}


	/**
	* Gets the number attribute of the LittleEndian class
	*
	*@param data Description of the Parameter
	*@param offset Description of the Parameter
	*@param size Description of the Parameter
	*@return The number value
	*/
	private static long getNumber(final byte[] data, final int offset,
	final int size) {
	long result = 0;

	for (int j = offset + size - 1; j >= offset; j--) {
	result <<= 8;
	result \|= 0xff & data[j];
	}
	return result;
	}


	/**
	* Description of the Method
	*
	*@param data Description of the Parameter
	*@param offset Description of the Parameter
	*@param value Description of the Parameter
	*@param size Description of the Parameter
	*/
	private static void putNumber(final byte[] data, final int offset,
	final long value, final int size) {
	int limit = size + offset;
	long v = value;

	for (int j = offset; j < limit; j++) {
	data[j] = (byte) (v & 0xFF);
	v >>= 8;
	}
	}


	/**
	* Convert an 'unsigned' byte to an integer. ie, don't carry across the
	* sign.
	*
	*@param b Description of the Parameter
	*@return Description of the Return Value
	*/
	public static int ubyteToInt(byte b) {
	return ((b & 0x80) == 0 ? (int) b : (int) (b & (byte) 0x7f) + 0x80);
	}


	/**
	* get the unsigned value of a byte.
	*
	*@param data the byte array.
	*@param offset a starting offset into the byte array.
	*@return the unsigned value of the byte as a 32 bit integer
	*/
	public static int getUnsignedByte(final byte[] data, final int offset) {
	return (int) getNumber(data, offset, BYTE_SIZE);
	}


	/**
	* get the unsigned value of a byte.
	*
	*@param data the byte array
	*@return the unsigned value of the byte as a 32 bit integer
	*/
	public static int getUnsignedByte(final byte[] data) {
	return getUnsignedByte(data, 0);
	}


	/**
	* Copy a portion of a byte array
	*
	*@param data the original byte array
	*@param offset Where to start copying from.
	*@param size Number of bytes to copy.
	*@return The byteArray value
	*@throws IndexOutOfBoundsException - if copying would cause access of
	* data outside array bounds.
	*/
	public static byte[] getByteArray(final byte[] data, int offset, int size) {
	byte[] copy = new byte[size];
	System.arraycopy(data, offset, copy, 0, size);

	return copy;
	}


	}