gomp-20050608-branch/libjava/classpath/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., 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 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     if (pos >= limit)
 148         throw new BufferUnderflowException();
 149
 150     return backing_buffer [(pos++) + array_offset];
 151   }
 152
 153   /**
 154    * Bulk get
 155    */
 156   public ByteBuffer get (byte[] dst, int offset, int length)
 157   {
 158     checkArraySize(dst.length, offset, length);
 159     if ( (limit - pos) < length) // check for overflow
 160       throw new BufferUnderflowException();
 161
 162     System.arraycopy(backing_buffer, pos + array_offset,
 163                      dst, offset, length);
 164     pos += length;
 165
 166     return this;
 167   }
 168
 169   /**
 170    * Relative bulk put(), overloads the ByteBuffer impl.
 171    */
 172   public ByteBuffer put (byte[] src, int offset, int length)
 173   {
 174     if ( (limit - pos) < length) // check for overflow
 175       throw new BufferOverflowException();
 176     checkArraySize(src.length, offset, length);
 177
 178     System.arraycopy(src, offset, backing_buffer, pos + array_offset, length);
 179     pos += length;
 180
 181     return this;
 182   }
 183
 184   /**
 185    * Relative put method. Writes <code>value</code> to the next position
 186    * in the buffer.
 187    *
 188    * @exception BufferOverflowException If there is no remaining
 189    * space in this buffer.
 190    * @exception ReadOnlyBufferException If this buffer is read-only.
 191    */
 192   public ByteBuffer put (byte value)
 193   {
 194     if (readOnly)
 195         throw new ReadOnlyBufferException();
 196     if (pos >= limit)
 197         throw new BufferOverflowException();
 198
 199     backing_buffer [(pos++) + array_offset] = value;
 200     return this;
 201   }
 202
 203   /**
 204    * Absolute get method. Reads the <code>byte</code> at position
 205    * <code>index</code>.
 206    *
 207    * @exception IndexOutOfBoundsException If index is negative or not smaller
 208    * than the buffer's limit.
 209    */
 210   public byte get (int index)
 211   {
 212     checkIndex(index);
 213
 214     return backing_buffer [index + array_offset];
 215   }
 216
 217   /**
 218    * Absolute put method. Writes <code>value</code> to position
 219    * <code>index</code> in the buffer.
 220    *
 221    * @exception IndexOutOfBoundsException If index is negative or not smaller
 222    * than the buffer's limit.
 223    * @exception ReadOnlyBufferException If this buffer is read-only.
 224    */
 225   public ByteBuffer put (int index, byte value)
 226   {
 227     checkIfReadOnly();
 228     checkIndex(index);
 229
 230     backing_buffer [index + array_offset] = value;
 231     return this;
 232   }
 233
 234   public char getChar ()
 235   {
 236     return ByteBufferHelper.getChar(this, order());
 237   }
 238
 239   public ByteBuffer putChar (char value)
 240   {
 241     if (readOnly)
 242       throw new ReadOnlyBufferException ();
 243     if ( (limit-pos) < 2)
 244       throw new BufferOverflowException();
 245
 246     if (endian == ByteOrder.LITTLE_ENDIAN)
 247       {
 248         backing_buffer [(pos++) + array_offset] = (byte)(value&0xFF);
 249         backing_buffer [(pos++) + array_offset] = (byte)(value>>8);
 250       }
 251     else
 252       {
 253         backing_buffer [(pos++) + array_offset] = (byte)(value>>8);
 254         backing_buffer [(pos++) + array_offset] = (byte)(value&0xFF);
 255       }
 256     return this;
 257   }
 258
 259   public char getChar (int index)
 260   {
 261     return ByteBufferHelper.getChar(this, index, order());
 262   }
 263
 264   public ByteBuffer putChar (int index, char value)
 265   {
 266     ByteBufferHelper.putChar(this, index, value, order());
 267     return this;
 268   }
 269
 270   public short getShort ()
 271   {
 272     return ByteBufferHelper.getShort(this, order());
 273   }
 274
 275   public ByteBuffer putShort (short value)
 276   {
 277     ByteBufferHelper.putShort(this, value, order());
 278     return this;
 279   }
 280
 281   public short getShort (int index)
 282   {
 283     return ByteBufferHelper.getShort(this, index, order());
 284   }
 285
 286   public ByteBuffer putShort (int index, short value)
 287   {
 288     ByteBufferHelper.putShort(this, index, value, order());
 289     return this;
 290   }
 291
 292   public int getInt ()
 293   {
 294     return ByteBufferHelper.getInt(this, order());
 295   }
 296
 297   public ByteBuffer putInt (int value)
 298   {
 299     ByteBufferHelper.putInt(this, value, order());
 300     return this;
 301   }
 302
 303   public int getInt (int index)
 304   {
 305     return ByteBufferHelper.getInt(this, index, order());
 306   }
 307
 308   public ByteBuffer putInt (int index, int value)
 309   {
 310     ByteBufferHelper.putInt(this, index, value, order());
 311     return this;
 312   }
 313
 314   public long getLong ()
 315   {
 316     return ByteBufferHelper.getLong(this, order());
 317   }
 318
 319   public ByteBuffer putLong (long value)
 320   {
 321     ByteBufferHelper.putLong (this, value, order());
 322     return this;
 323   }
 324
 325   public long getLong (int index)
 326   {
 327     return ByteBufferHelper.getLong (this, index, order());
 328   }
 329
 330   public ByteBuffer putLong (int index, long value)
 331   {
 332     ByteBufferHelper.putLong (this, index, value, order());
 333     return this;
 334   }
 335
 336   public float getFloat ()
 337   {
 338     return ByteBufferHelper.getFloat (this, order());
 339   }
 340
 341   public ByteBuffer putFloat (float value)
 342   {
 343     ByteBufferHelper.putFloat (this, value, order());
 344     return this;
 345   }
 346
 347   public float getFloat (int index)
 348   {
 349     return ByteBufferHelper.getFloat (this, index, order());
 350   }
 351
 352   public ByteBuffer putFloat (int index, float value)
 353   {
 354     ByteBufferHelper.putFloat (this, index, value, order());
 355     return this;
 356   }
 357
 358   public double getDouble ()
 359   {
 360     return ByteBufferHelper.getDouble (this, order());
 361   }
 362
 363   public ByteBuffer putDouble (double value)
 364   {
 365     ByteBufferHelper.putDouble (this, value, order());
 366     return this;
 367   }
 368
 369   public double getDouble (int index)
 370   {
 371     return ByteBufferHelper.getDouble (this, index, order());
 372   }
 373
 374   public ByteBuffer putDouble (int index, double value)
 375   {
 376     ByteBufferHelper.putDouble (this, index, value, order());
 377     return this;
 378   }
 379 }