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| <img src="../../../../boost.png" width="276" height="86" alt="C++ Boost"> |
| |
| <h1 align="center">Object Pool Implementation</h1> |
| |
| <h2>Dependencies</h2> |
| |
| <p>Includes the Boost header <span class="code">"pool.hpp"</span> (see |
| <a href="pool.html">pool.html</a>).</p> |
| |
| <h2>Extensions to Public Interface</h2> |
| |
| <p>Whenever an object of type <span class="code">ObjectPool</span> needs |
| memory from the system, it will request it from its <span class= |
| "code">UserAllocator</span> template parameter. The amount requested is |
| determined using a doubling algorithm; that is, each time more system |
| memory is allocated, the amount of system memory requested is doubled. |
| Users may control the doubling algorithm by using the following |
| extensions.</p> |
| |
| <h3>Additional constructor parameter</h3> |
| |
| <p>Users may pass an additional constructor parameter to <span class= |
| "code">ObjectPool</span>. This parameter is of type <span class= |
| "code">size_type</span>, and is the number of chunks to request from the |
| system the first time that object needs to allocate system memory. The |
| default is 32. This parameter may not be 0.</p> |
| |
| <h3><span class="code">next_size</span> accessor functions</h3> |
| |
| <p>The pair of functions <span class="code">size_type get_next_size() |
| const;</span> and <span class="code">void set_next_size(size_type);</span> |
| allow users to explicitly read and write the <span class= |
| "code">next_size</span> value. This value is the number of chunks to |
| request from the system the next time that object needs to allocate system |
| memory. This value should never be set to 0.</p> |
| |
| <h2>Protected Interface</h2> |
| |
| <h3>Synopsis</h3> |
| <pre class="code"> |
| template <typename ElementType, typename UserAllocator = default_user_allocator_new_delete> |
| class object_pool: protected pool<UserAllocator> |
| { |
| ... // public interface |
| }; |
| </pre> |
| |
| <h3>Protected Derivation</h3>ObjectPool derives from a simple segregated |
| storage via protected derivation; this exposes all the <a href= |
| "pool.html">Pool implementation details</a> to all classes derived from |
| ObjectPool as well. |
| |
| <h2><a href="../interfaces/object_pool.html">Interface Description</a></h2> |
| <hr> |
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| <p>Revised |
| <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->05 |
| December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38516" --></p> |
| |
| <p><i>Copyright © 2000, 2001 Stephen Cleary (scleary AT jerviswebb DOT |
| com)</i></p> |
| |
| <p><i>Distributed under the Boost Software License, Version 1.0. (See |
| accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> |
| or copy at <a href= |
| "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p> |
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