libjava/gnu/java/nio/DoubleBufferImpl.java

   1 /* DoubleBufferImpl.java --
   2    Copyright (C) 2002 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 package gnu.java.nio;
  39
  40 import java.nio.ByteBuffer;
  41 import java.nio.ByteOrder;
  42 import java.nio.DoubleBuffer;
  43 import java.nio.ReadOnlyBufferException;
  44
  45 /**
  46  * This is a Heap memory implementation
  47  */
  48 public final class DoubleBufferImpl extends DoubleBuffer
  49 {
  50   private boolean readOnly;
  51
  52   public DoubleBufferImpl(int cap, int off, int lim)
  53   {
  54     super (cap, lim, off, 0);
  55     this.backing_buffer = new double[cap];
  56     readOnly = false;
  57   }
  58
  59   public DoubleBufferImpl(double[] array, int offset, int length)
  60   {
  61     super (array.length, length, offset, 0);
  62     this.backing_buffer = array;
  63     readOnly = false;
  64   }
  65
  66   public DoubleBufferImpl(DoubleBufferImpl copy)
  67   {
  68     super (copy.capacity (), copy.limit (), copy.position (), 0);
  69     backing_buffer = copy.backing_buffer;
  70     readOnly = copy.isReadOnly ();
  71   }
  72
  73   DoubleBufferImpl (byte[] copy)
  74   {
  75     super (copy.length, copy.length, 0, 0);
  76     this.backing_buffer = copy != null ? nio_cast (copy) : null;
  77     readOnly = false;
  78   }
  79
  80   private static native byte nio_get_Byte (DoubleBufferImpl b, int index, int limit);
  81
  82   private static native void nio_put_Byte (DoubleBufferImpl b, int index, int limit, byte value);
  83
  84   public ByteBuffer asByteBuffer ()
  85   {
  86     ByteBufferImpl res = new ByteBufferImpl (backing_buffer);
  87     res.limit ((limit () * 1) / 8);
  88     return res;
  89   }
  90
  91   private static native double[] nio_cast (byte[] copy);
  92
  93   public boolean isReadOnly ()
  94   {
  95     return readOnly;
  96   }
  97
  98   public DoubleBuffer slice ()
  99   {
 100     return new DoubleBufferImpl (this);
 101   }
 102
 103   public DoubleBuffer duplicate()
 104   {
 105     return new DoubleBufferImpl(this);
 106   }
 107
 108   public DoubleBuffer asReadOnlyBuffer()
 109   {
 110     DoubleBufferImpl result = new DoubleBufferImpl (this);
 111     result.readOnly = true;
 112     return result;
 113   }
 114
 115   public DoubleBuffer compact()
 116   {
 117     return this;
 118   }
 119
 120   public boolean isDirect()
 121   {
 122     return false;
 123   }
 124
 125   final public double get()
 126   {
 127     double e = backing_buffer[position()];
 128     position(position()+1);
 129     return e;
 130   }
 131
 132   final public DoubleBuffer put(double b)
 133   {
 134     if (readOnly)
 135       throw new ReadOnlyBufferException ();
 136
 137     backing_buffer[position()] = b;
 138     position(position()+1);
 139     return this;
 140   }
 141
 142   final public double get(int index)
 143   {
 144     return backing_buffer[index];
 145   }
 146
 147   final public DoubleBuffer put(int index, double b)
 148   {
 149     if (readOnly)
 150       throw new ReadOnlyBufferException ();
 151
 152     backing_buffer[index] = b;
 153     return this;
 154   }
 155
 156   final public ByteOrder order ()
 157   {
 158     return ByteOrder.BIG_ENDIAN;
 159   }
 160 }