Symbian3/SDK/Source/GUID-D37E0579-0F3B-5EE4-8264-1358E493672B.dita
author Dominic Pinkman <Dominic.Pinkman@Nokia.com>
Thu, 21 Jan 2010 18:18:20 +0000
changeset 0 89d6a7a84779
permissions -rw-r--r--
Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
0
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     1
<?xml version="1.0" encoding="utf-8"?>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     2
<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     3
<!-- This component and the accompanying materials are made available under the terms of the License 
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     4
"Eclipse Public License v1.0" which accompanies this distribution, 
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     5
and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     6
<!-- Initial Contributors:
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     7
    Nokia Corporation - initial contribution.
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     8
Contributors: 
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
     9
-->
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    10
<!DOCTYPE concept
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    11
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    12
<concept id="GUID-D37E0579-0F3B-5EE4-8264-1358E493672B" xml:lang="en"><title>Array
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    13
of variable length elements, flat buffer</title><shortdesc>Describes how elements of varying length are organised in the array
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    14
buffer.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    15
<p>This is a <codeph>CArrayVarFlat&lt;class T&gt;</codeph> object whose
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    16
elements can have different lengths. Although each element is a <codeph>class T</codeph> object,
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    17
the length of that object can vary.</p>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    18
<p>In this type of array, each element occupies its own individual cell allocated
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    19
from the heap. The array buffer contains fixed length data structures, one
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    20
for each element, which are physically contiguous within the flat array buffer.
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    21
Each fixed length data structure contains the length of an element (a <codeph>TInt</codeph> value)
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    22
and a pointer to it. The structure itself is part of the implementation but
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    23
occupies no more than eight bytes on 32-bit machines.</p>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    24
<p>A flat buffer always occupies a single cell allocated from the heap and
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    25
is always extended by the process of reallocation. A flat array buffer is
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    26
implemented using a <codeph>CBufFlat</codeph> object.</p>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    27
<p>The following diagram illustrates how elements are organised within the
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    28
array buffer:</p>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    29
<fig id="GUID-2A857FBF-943D-5665-9999-BC27EA321F73">
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    30
<image href="GUID-924E26D6-8B9D-5C76-AF61-7C5514BB3D78_d0e190846_href.png" placement="inline"/>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    31
</fig>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    32
<p>This kind of array is suitable for a small number of elements or for a
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    33
moderately large but fixed maximum number of elements. It is not suitable
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    34
for large arrays with a high turnover of elements. </p>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    35
<p>This class is immediately derived from the abstract templated base class <codeph>CArrayVar&lt;class T&gt;</codeph> which
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    36
is itself derived from the abstract non-templated base class <codeph>CArrayVarBase</codeph>.</p>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    37
<section id="GUID-59ADA2D7-56B2-44C3-8E7C-A5DE5F0BBDBA"><title>See also</title> <p><xref href="GUID-112AAFA5-B4C9-5B62-A106-FB5097C13A0E.dita">Using
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    38
Dynamic Buffers</xref>.</p> </section>
89d6a7a84779 Initial contribution of Documentation_content according to Feature bug 1266 bug 1268 bug 1269 bug 1270 bug 1372 bug 1374 bug 1375 bug 1379 bug 1380 bug 1381 bug 1382 bug 1383 bug 1385
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    39
</conbody></concept>