libjava/java/nio/ByteBufferImpl.java

   1 /* ByteBufferImpl.java --
   2    Copyright (C) 2002, 2003, 2004, 2005  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., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 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 ByteBufferImpl extends ByteBuffer
  45 {
  46   private boolean readOnly;
  47
  48   ByteBufferImpl (byte[] buffer, int offset, int capacity, int limit, int position, int mark, boolean readOnly)
  49   {
  50     super (capacity, limit, position, mark);
  51     this.backing_buffer = buffer;
  52     this.array_offset = offset;
  53     this.readOnly = readOnly;
  54   }
  55
  56   public CharBuffer asCharBuffer ()
  57   {
  58     return new CharViewBufferImpl (this, remaining() >> 1);
  59   }
  60
  61   public ShortBuffer asShortBuffer ()
  62   {
  63     return new ShortViewBufferImpl (this, remaining() >> 1);
  64   }
  65
  66   public IntBuffer asIntBuffer ()
  67   {
  68     return new IntViewBufferImpl (this, remaining() >> 2);
  69   }
  70
  71   public LongBuffer asLongBuffer ()
  72   {
  73     return new LongViewBufferImpl (this, remaining() >> 3);
  74   }
  75
  76   public FloatBuffer asFloatBuffer ()
  77   {
  78     return new FloatViewBufferImpl (this, remaining() >> 2);
  79   }
  80
  81   public DoubleBuffer asDoubleBuffer ()
  82   {
  83     return new DoubleViewBufferImpl (this, remaining() >> 3);
  84   }
  85
  86   public boolean isReadOnly ()
  87   {
  88     return readOnly;
  89   }
  90
  91   public ByteBuffer slice ()
  92   {
  93     return new ByteBufferImpl (backing_buffer, array_offset + position (), remaining (), remaining (), 0, -1, isReadOnly ());
  94   }
  95
  96   public ByteBuffer duplicate ()
  97   {
  98     return new ByteBufferImpl (backing_buffer, array_offset, capacity (), limit (), position (), mark, isReadOnly ());
  99   }
 100
 101   public ByteBuffer asReadOnlyBuffer ()
 102   {
 103     return new ByteBufferImpl (backing_buffer, array_offset, capacity (), limit (), position (), mark, true);
 104   }
 105
 106   void shiftDown (int dst_offset, int src_offset, int count)
 107   {
 108     System.arraycopy(backing_buffer, array_offset + src_offset,
 109                      backing_buffer, array_offset + dst_offset,
 110                      count);
 111   }
 112
 113   public ByteBuffer compact ()
 114   {
 115     checkIfReadOnly();
 116     mark = -1;
 117     int pos = position();
 118     if (pos > 0)
 119       {
 120         int count = remaining();
 121         shiftDown(0, pos, count);
 122         position(count);
 123         limit(capacity());
 124       }
 125     else
 126       {
 127         position(limit());
 128         limit(capacity());
 129       }
 130     return this;
 131   }
 132
 133   public boolean isDirect ()
 134   {
 135     return false;
 136   }
 137
 138   /**
 139    * Reads the <code>byte</code> at this buffer's current position,
 140    * and then increments the position.
 141    *
 142    * @exception BufferUnderflowException If there are no remaining
 143    * <code>bytes</code> in this buffer.
 144    */
 145   public byte get ()
 146   {
 147     checkForUnderflow();
 148
 149     byte result = backing_buffer [position () + array_offset];
 150     position (position () + 1);
 151     return result;
 152   }
 153
 154   /**
 155    * Relative put method. Writes <code>value</code> to the next position
 156    * in the buffer.
 157    *
 158    * @exception BufferOverflowException If there is no remaining
 159    * space in this buffer.
 160    * @exception ReadOnlyBufferException If this buffer is read-only.
 161    */
 162   public ByteBuffer put (byte value)
 163   {
 164     checkIfReadOnly();
 165     checkForOverflow();
 166
 167     int pos = position();
 168     backing_buffer [pos + array_offset] = value;
 169     position (pos + 1);
 170     return this;
 171   }
 172
 173   /**
 174    * Absolute get method. Reads the <code>byte</code> at position
 175    * <code>index</code>.
 176    *
 177    * @exception IndexOutOfBoundsException If index is negative or not smaller
 178    * than the buffer's limit.
 179    */
 180   public byte get (int index)
 181   {
 182     checkIndex(index);
 183
 184     return backing_buffer [index + array_offset];
 185   }
 186
 187   /**
 188    * Absolute put method. Writes <code>value</code> to position
 189    * <code>index</code> in the buffer.
 190    *
 191    * @exception IndexOutOfBoundsException If index is negative or not smaller
 192    * than the buffer's limit.
 193    * @exception ReadOnlyBufferException If this buffer is read-only.
 194    */
 195   public ByteBuffer put (int index, byte value)
 196   {
 197     checkIfReadOnly();
 198     checkIndex(index);
 199
 200     backing_buffer [index + array_offset] = value;
 201     return this;
 202   }
 203
 204   public char getChar ()
 205   {
 206     return ByteBufferHelper.getChar(this, order());
 207   }
 208
 209   public ByteBuffer putChar (char value)
 210   {
 211     ByteBufferHelper.putChar(this, value, order());
 212     return this;
 213   }
 214
 215   public char getChar (int index)
 216   {
 217     return ByteBufferHelper.getChar(this, index, order());
 218   }
 219
 220   public ByteBuffer putChar (int index, char value)
 221   {
 222     ByteBufferHelper.putChar(this, index, value, order());
 223     return this;
 224   }
 225
 226   public short getShort ()
 227   {
 228     return ByteBufferHelper.getShort(this, order());
 229   }
 230
 231   public ByteBuffer putShort (short value)
 232   {
 233     ByteBufferHelper.putShort(this, value, order());
 234     return this;
 235   }
 236
 237   public short getShort (int index)
 238   {
 239     return ByteBufferHelper.getShort(this, index, order());
 240   }
 241
 242   public ByteBuffer putShort (int index, short value)
 243   {
 244     ByteBufferHelper.putShort(this, index, value, order());
 245     return this;
 246   }
 247
 248   public int getInt ()
 249   {
 250     return ByteBufferHelper.getInt(this, order());
 251   }
 252
 253   public ByteBuffer putInt (int value)
 254   {
 255     ByteBufferHelper.putInt(this, value, order());
 256     return this;
 257   }
 258
 259   public int getInt (int index)
 260   {
 261     return ByteBufferHelper.getInt(this, index, order());
 262   }
 263
 264   public ByteBuffer putInt (int index, int value)
 265   {
 266     ByteBufferHelper.putInt(this, index, value, order());
 267     return this;
 268   }
 269
 270   public long getLong ()
 271   {
 272     return ByteBufferHelper.getLong(this, order());
 273   }
 274
 275   public ByteBuffer putLong (long value)
 276   {
 277     ByteBufferHelper.putLong (this, value, order());
 278     return this;
 279   }
 280
 281   public long getLong (int index)
 282   {
 283     return ByteBufferHelper.getLong (this, index, order());
 284   }
 285
 286   public ByteBuffer putLong (int index, long value)
 287   {
 288     ByteBufferHelper.putLong (this, index, value, order());
 289     return this;
 290   }
 291
 292   public float getFloat ()
 293   {
 294     return ByteBufferHelper.getFloat (this, order());
 295   }
 296
 297   public ByteBuffer putFloat (float value)
 298   {
 299     ByteBufferHelper.putFloat (this, value, order());
 300     return this;
 301   }
 302
 303   public float getFloat (int index)
 304   {
 305     return ByteBufferHelper.getFloat (this, index, order());
 306   }
 307
 308   public ByteBuffer putFloat (int index, float value)
 309   {
 310     ByteBufferHelper.putFloat (this, index, value, order());
 311     return this;
 312   }
 313
 314   public double getDouble ()
 315   {
 316     return ByteBufferHelper.getDouble (this, order());
 317   }
 318
 319   public ByteBuffer putDouble (double value)
 320   {
 321     ByteBufferHelper.putDouble (this, value, order());
 322     return this;
 323   }
 324
 325   public double getDouble (int index)
 326   {
 327     return ByteBufferHelper.getDouble (this, index, order());
 328   }
 329
 330   public ByteBuffer putDouble (int index, double value)
 331   {
 332     ByteBufferHelper.putDouble (this, index, value, order());
 333     return this;
 334   }
 335 }