libjava/classpath/java/nio/CharBufferImpl.java

   1 /* CharBufferImpl.java --
   2    Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.nio;
  40
  41 /**
  42  * This is a Heap memory implementation
  43  */
  44 final class CharBufferImpl extends CharBuffer
  45 {
  46   private final boolean readOnly;
  47
  48   CharBufferImpl (int capacity)
  49   {
  50     this (new char [capacity], 0, capacity, capacity, 0, -1, false);
  51   }
  52
  53   CharBufferImpl (char[] buffer, int offset, int capacity, int limit, int position, int mark, boolean readOnly)
  54   {
  55     super (capacity, limit, position, mark, null, buffer, offset);
  56     this.readOnly = readOnly;
  57   }
  58
  59   public CharBufferImpl (CharBufferImpl copy)
  60   {
  61     super (copy.capacity (), copy.limit (), copy.position (), 0, null, copy.backing_buffer, copy.array_offset);
  62     this.readOnly = copy.isReadOnly ();
  63   }
  64
  65   public boolean isReadOnly ()
  66   {
  67     return readOnly;
  68   }
  69
  70   public CharBuffer slice ()
  71   {
  72     return new CharBufferImpl (backing_buffer, array_offset + position (), remaining (), remaining (), 0, -1, isReadOnly ());
  73   }
  74
  75   public CharBuffer duplicate ()
  76   {
  77     return new CharBufferImpl (backing_buffer, array_offset, capacity (), limit (), position (), mark, isReadOnly ());
  78   }
  79
  80   public CharBuffer asReadOnlyBuffer ()
  81   {
  82     return new CharBufferImpl (backing_buffer, array_offset, capacity (), limit (), position (), mark, true);
  83   }
  84
  85   public CharBuffer compact ()
  86   {
  87     checkIfReadOnly();
  88     mark = -1;
  89     int p = position();
  90     int n = limit() - p;
  91     if (n > 0)
  92       {
  93         System.arraycopy(backing_buffer, array_offset + p,
  94                          backing_buffer, array_offset, n);
  95       }
  96     position(n);
  97     limit(capacity());
  98     return this;
  99   }
 100
 101   public boolean isDirect ()
 102   {
 103     return false;
 104   }
 105
 106   public CharSequence subSequence (int start, int end)
 107   {
 108     if (start < 0
 109         || start > length ()
 110         || end < start
 111         || end > length ())
 112       throw new IndexOutOfBoundsException ();
 113
 114     return new CharBufferImpl (backing_buffer, array_offset, capacity (), position () + end, position () + start, -1, isReadOnly ());
 115   }
 116
 117   /**
 118    * Reads the <code>char</code> at this buffer's current position,
 119    * and then increments the position.
 120    *
 121    * @exception BufferUnderflowException If there are no remaining
 122    * <code>char</code>s in this buffer.
 123    */
 124   public char get ()
 125   {
 126     if (pos >= limit)
 127         throw new BufferUnderflowException();
 128
 129     return backing_buffer [(pos++) + array_offset];
 130   }
 131
 132   /**
 133    * Relative put method. Writes <code>value</code> to the next position
 134    * in the buffer.
 135    *
 136    * @exception ReadOnlyBufferException If this buffer is read-only.
 137    */
 138   public CharBuffer put (char value)
 139   {
 140     if (readOnly)
 141         throw new ReadOnlyBufferException();
 142     if (pos >= limit)
 143         throw new BufferOverflowException();
 144
 145     backing_buffer [(pos++) + array_offset] = value;
 146     return this;
 147   }
 148
 149   /**
 150    * Absolute get method. Reads the <code>char</code> at position
 151    * <code>index</code>.
 152    *
 153    * @param index Position to read the <code>char</code> from.
 154    *
 155    * @exception IndexOutOfBoundsException If index is negative or not smaller
 156    * than the buffer's limit.
 157    */
 158   public char get (int index)
 159   {
 160     checkIndex(index);
 161
 162     return backing_buffer [index + array_offset];
 163   }
 164
 165   /**
 166    * Bulk get, overloaded for speed.
 167    */
 168   public CharBuffer get (char[] dst, int offset, int length)
 169   {
 170     checkArraySize(dst.length, offset, length);
 171     checkForUnderflow(length);
 172
 173     System.arraycopy(backing_buffer, pos + array_offset,
 174                      dst, offset, length);
 175     pos += length;
 176     return this;
 177   }
 178
 179   /**
 180    * Bulk put, overloaded for speed.
 181    */
 182   public CharBuffer put (char[] src, int offset, int length)
 183   {
 184     checkArraySize(src.length, offset, length);
 185     checkForOverflow(length);
 186
 187     System.arraycopy(src, offset,
 188                      backing_buffer, pos + array_offset, length);
 189     pos += length;
 190     return this;
 191   }
 192
 193   /**
 194    * Absolute put method. Writes <code>value</code> to position
 195    * <code>index</code> in the buffer.
 196    *
 197    * @exception IndexOutOfBoundsException If index is negative or not smaller
 198    * than the buffer's limit.
 199    * @exception ReadOnlyBufferException If this buffer is read-only.
 200    */
 201   public CharBuffer put (int index, char value)
 202   {
 203     checkIndex(index);
 204     checkIfReadOnly();
 205
 206     backing_buffer [index + array_offset] = value;
 207     return this;
 208   }
 209
 210   public ByteOrder order ()
 211   {
 212     return ByteOrder.nativeOrder ();
 213   }
 214 }