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54   * Portions of this software are based upon public domain software
55   * originally written at the National Center for Supercomputing Applications,
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58    * Portions of this software are based upon public domain software
59    * originally written at the National Center for Supercomputing Applications,
60    * University of Illinois, Urbana-Champaign.
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62   
63   package org.apache.poi.hpsf.littleendian;
64   
65   /**
66    * <p>A data item in the little-endian format. Little-endian means
67    * that lower bytes come before higher bytes.</p>
68    *
69    * @author Rainer Klute (klute@rainer-klute.de)
70    * @version $Id: LittleEndian.java,v 1.2 2002/04/30 03:51:02 acoliver Exp $
71    * @since 2002-02-09
72    */
73   public abstract class LittleEndian
74   {
75   
76       /* This class could be optimized by not copying the bytes, but
77        * instead maintaining just references to the original byte
78        * arrays. However, before implementing this it should be
79        * investigated whether it is worth the while. */
80   
81   
82       /**
83        * <p>The bytes making out the little-endian field. They are in
84        * correct order, i.e. high-endian.</p>
85        */
86       protected byte[] bytes;
87   
88   
89   
90       /**
91        * <p>Creates a {@link LittleEndian} and reads its value from a
92        * byte array.</p>
93        *
94        * @param src The byte array to read from.
95        *
96        * @param offset The offset of the first byte to read.
97        */
98       public LittleEndian(final byte[] src, final int offset)
99       {
100          read(src, offset);
101      }
102  
103  
104  
105      /**
106       * <p>Returns the bytes making out the little-endian field in
107       * big-endian order.
108       </p> */
109      public byte[] getBytes()
110      {
111          return bytes;
112      }
113  
114  
115  
116      /**
117       * <p>Reads the little-endian field from a byte array.</p>
118       *
119       * @param src The byte array to read from
120       *
121       * @param offset The offset within the <var>src</var> byte array
122       */
123      public byte[] read(final byte[] src, final int offset)
124      {
125          final int length = length();
126          bytes = new byte[length];
127          for (int i = 0; i < length; i++)
128              bytes[i] = src[offset + length - 1 - i];
129          return bytes;
130      }
131  
132  
133      /**
134       * <p>Returns the number of bytes of this little-endian field.</p>
135       */
136      public abstract int length();
137  
138  }
139