1 /* LongViewBufferImpl.java --
2 Copyright (C) 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 final class LongViewBufferImpl extends LongBuffer
42 {
43 /** Position in bb (i.e. a byte offset) where this buffer starts. */
44 private int offset;
45 private ByteBuffer bb;
46 private boolean readOnly;
47 private ByteOrder endian;
48
49 LongViewBufferImpl (ByteBuffer bb, int capacity)
50 {
51 super (capacity, capacity, 0, -1);
52 this.bb = bb;
53 this.offset = bb.position();
54 this.readOnly = bb.isReadOnly();
55 this.endian = bb.order();
56 if (bb.isDirect())
57 this.address = VMDirectByteBuffer.adjustAddress(bb.address, offset);
58 }
59
60 public LongViewBufferImpl (ByteBuffer bb, int offset, int capacity,
61 int limit, int position, int mark,
62 boolean readOnly, ByteOrder endian)
63 {
64 super (capacity, limit, position, mark);
65 this.bb = bb;
66 this.offset = offset;
67 this.readOnly = readOnly;
68 this.endian = endian;
69 if (bb.isDirect())
70 this.address = VMDirectByteBuffer.adjustAddress(bb.address, offset);
71 }
72
73 /**
74 * Reads the <code>long</code> at this buffer's current position,
75 * and then increments the position.
76 *
77 * @exception BufferUnderflowException If there are no remaining
78 * <code>longs</code> in this buffer.
79 */
80 public long get ()
81 {
82 int p = position();
83 long result = ByteBufferHelper.getLong(bb, (p << 3) + offset, endian);
84 position(p + 1);
85 return result;
86 }
87
88 /**
89 * Absolute get method. Reads the <code>long</code> at position
90 * <code>index</code>.
91 *
92 * @exception IndexOutOfBoundsException If index is negative or not smaller
93 * than the buffer's limit.
94 */
95 public long get (int index)
96 {
97 return ByteBufferHelper.getLong(bb, (index << 3) + offset, endian);
98 }
99
100 public LongBuffer put (long value)
101 {
102 int p = position();
103 ByteBufferHelper.putLong(bb, (p << 3) + offset, value, endian);
104 position(p + 1);
105 return this;
106 }
107
108 public LongBuffer put (int index, long value)
109 {
110 ByteBufferHelper.putLong(bb, (index << 3) + offset, value, endian);
111 return this;
112 }
113
114 public LongBuffer compact ()
115 {
116 if (position () > 0)
117 {
118 int count = limit () - position ();
119 bb.shiftDown(offset, offset + 8 * position(), 8 * count);
120 position (count);
121 limit (capacity ());
122 }
123 else
124 {
125 position(limit());
126 limit(capacity());
127 }
128 return this;
129 }
130
131 public LongBuffer slice ()
132 {
133 // Create a sliced copy of this object that shares its content.
134 return new LongViewBufferImpl (bb, (position () >> 3) + offset,
135 remaining(), remaining(), 0, -1,
136 readOnly, endian);
137 }
138
139 LongBuffer duplicate (boolean readOnly)
140 {
141 int pos = position();
142 reset();
143 int mark = position();
144 position(pos);
145 return new LongViewBufferImpl (bb, offset, capacity(), limit(),
146 pos, mark, readOnly, endian);
147 }
148
149 public LongBuffer duplicate ()
150 {
151 return duplicate(readOnly);
152 }
153
154 public LongBuffer asReadOnlyBuffer ()
155 {
156 return duplicate(true);
157 }
158
159 public boolean isReadOnly ()
160 {
161 return readOnly;
162 }
163
164 public boolean isDirect ()
165 {
166 return bb.isDirect ();
167 }
168
169 public ByteOrder order ()
170 {
171 return endian;
172 }
173 }
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