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<a name="134" href="#134">134</a>             }
<a name="135" href="#135">135</a>             <strong>if</strong>(<strong>null</strong> != _factory &amp;&amp; <strong>null</strong> != obj) {
<a name="136" href="#136">136</a>                 _factory.activateObject(obj);
<a name="137" href="#137">137</a>             }
<a name="138" href="#138">138</a>             <strong>if</strong> (<strong>null</strong> != _factory &amp;&amp; <strong>null</strong> != obj &amp;&amp; !_factory.validateObject(obj)) {
<a name="139" href="#139">139</a>                 _factory.destroyObject(obj);
<a name="140" href="#140">140</a>                 obj = <strong>null</strong>;
<a name="141" href="#141">141</a>             }
<a name="142" href="#142">142</a>         }
<a name="143" href="#143">143</a>         _numActive++;
<a name="144" href="#144">144</a>         <strong>return</strong> obj;
<a name="145" href="#145">145</a>     }
<a name="146" href="#146">146</a> 
<a name="147" href="#147">147</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> returnObject(Object obj) throws Exception {
<a name="148" href="#148">148</a>         assertOpen();
<a name="149" href="#149">149</a>         <strong>boolean</strong> success = <strong>true</strong>;
<a name="150" href="#150">150</a>         <strong>if</strong>(<strong>null</strong> != _factory) {
<a name="151" href="#151">151</a>             <strong>if</strong>(!(_factory.validateObject(obj))) {
<a name="152" href="#152">152</a>                 success = false;
<a name="153" href="#153">153</a>             } <strong>else</strong> {
<a name="154" href="#154">154</a>                 <strong>try</strong> {
<a name="155" href="#155">155</a>                     _factory.passivateObject(obj);
<a name="156" href="#156">156</a>                 } <strong>catch</strong>(Exception e) {
<a name="157" href="#157">157</a>                     success = false;
<a name="158" href="#158">158</a>                 }
<a name="159" href="#159">159</a>             }
<a name="160" href="#160">160</a>         }
<a name="161" href="#161">161</a> 
<a name="162" href="#162">162</a>         <strong>boolean</strong> shouldDestroy = !success;
<a name="163" href="#163">163</a> 
<a name="164" href="#164">164</a>         _numActive--;
<a name="165" href="#165">165</a>         <strong>if</strong> (success) {
<a name="166" href="#166">166</a>             Object toBeDestroyed = <strong>null</strong>;
<a name="167" href="#167">167</a>             <strong>if</strong>(_pool.size() >= _maxSleeping) {
<a name="168" href="#168">168</a>                 shouldDestroy = <strong>true</strong>;
<a name="169" href="#169">169</a>                 toBeDestroyed = _pool.remove(0); <em class="comment">// remove the stalest object</em>
<a name="170" href="#170">170</a>             }
<a name="171" href="#171">171</a>             _pool.push(obj);
<a name="172" href="#172">172</a>             obj = toBeDestroyed; <em class="comment">// swap returned obj with the stalest one so it can be destroyed</em>
<a name="173" href="#173">173</a>         }
<a name="174" href="#174">174</a>         notifyAll(); <em class="comment">// _numActive has changed</em>
<a name="175" href="#175">175</a> 
<a name="176" href="#176">176</a>         <strong>if</strong>(shouldDestroy) { <em class="comment">// by constructor, shouldDestroy is false when _factory is null</em>
<a name="177" href="#177">177</a>             <strong>try</strong> {
<a name="178" href="#178">178</a>                 _factory.destroyObject(obj);
<a name="179" href="#179">179</a>             } <strong>catch</strong>(Exception e) {
<a name="180" href="#180">180</a>                 <em class="comment">// ignored</em>
<a name="181" href="#181">181</a>             }
<a name="182" href="#182">182</a>         }
<a name="183" href="#183">183</a>     }
<a name="184" href="#184">184</a> 
<a name="185" href="#185">185</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> invalidateObject(Object obj) throws Exception {
<a name="186" href="#186">186</a>         assertOpen();
<a name="187" href="#187">187</a>         _numActive--;
<a name="188" href="#188">188</a>         <strong>if</strong>(<strong>null</strong> != _factory ) {
<a name="189" href="#189">189</a>             _factory.destroyObject(obj);
<a name="190" href="#190">190</a>         }
<a name="191" href="#191">191</a>         notifyAll(); <em class="comment">// _numActive has changed</em>
<a name="192" href="#192">192</a>     }
<a name="193" href="#193">193</a> 
<a name="194" href="#194">194</a>     <strong>public</strong> <strong>synchronized</strong> <strong>int</strong> getNumIdle() {
<a name="195" href="#195">195</a>         assertOpen();
<a name="196" href="#196">196</a>         <strong>return</strong> _pool.size();
<a name="197" href="#197">197</a>     }
<a name="198" href="#198">198</a> 
<a name="199" href="#199">199</a>     <strong>public</strong> <strong>synchronized</strong> <strong>int</strong> getNumActive() {
<a name="200" href="#200">200</a>         assertOpen();
<a name="201" href="#201">201</a>         <strong>return</strong> _numActive;
<a name="202" href="#202">202</a>     }
<a name="203" href="#203">203</a> 
<a name="204" href="#204">204</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> clear() {
<a name="205" href="#205">205</a>         assertOpen();
<a name="206" href="#206">206</a>         <strong>if</strong>(<strong>null</strong> != _factory) {
<a name="207" href="#207">207</a>             Iterator it = _pool.iterator();
<a name="208" href="#208">208</a>             <strong>while</strong>(it.hasNext()) {
<a name="209" href="#209">209</a>                 <strong>try</strong> {
<a name="210" href="#210">210</a>                     _factory.destroyObject(it.next());
<a name="211" href="#211">211</a>                 } <strong>catch</strong>(Exception e) {
<a name="212" href="#212">212</a>                     <em class="comment">// ignore error, keep destroying the rest</em>
<a name="213" href="#213">213</a>                 }
<a name="214" href="#214">214</a>             }
<a name="215" href="#215">215</a>         }
<a name="216" href="#216">216</a>         _pool.clear();
<a name="217" href="#217">217</a>     }
<a name="218" href="#218">218</a> 
<a name="219" href="#219">219</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> close() throws Exception {
<a name="220" href="#220">220</a>         clear();
<a name="221" href="#221">221</a>         _pool = <strong>null</strong>;
<a name="222" href="#222">222</a>         _factory = <strong>null</strong>;
<a name="223" href="#223">223</a>         <strong>super</strong>.close();
<a name="224" href="#224">224</a>     }
<a name="225" href="#225">225</a> 
<a name="226" href="#226">226</a>     <em>/**<em>*</em></em>
<a name="227" href="#227">227</a> <em>     * Create an object, and place it into the pool.</em>
<a name="228" href="#228">228</a> <em>     * addObject() is useful for "pre-loading" a pool with idle objects.</em>
<a name="229" href="#229">229</a> <em>     * @throws Exception when the {@link #_factory} has a problem creating an object.</em>
<a name="230" href="#230">230</a> <em>     */</em>
<a name="231" href="#231">231</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> addObject() throws Exception {
<a name="232" href="#232">232</a>         assertOpen();
<a name="233" href="#233">233</a>         Object obj = _factory.makeObject();
<a name="234" href="#234">234</a>         _numActive++;   <em class="comment">// A little slimy - must do this because returnObject decrements it.</em>
<a name="235" href="#235">235</a>         <strong>this</strong>.returnObject(obj);
<a name="236" href="#236">236</a>     }
<a name="237" href="#237">237</a> 
<a name="238" href="#238">238</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> setFactory(<a href="../../../../../org/apache/commons/pool/PoolableObjectFactory.html">PoolableObjectFactory</a> factory) throws IllegalStateException {
<a name="239" href="#239">239</a>         assertOpen();
<a name="240" href="#240">240</a>         <strong>if</strong>(0 &lt; getNumActive()) {
<a name="241" href="#241">241</a>             <strong>throw</strong> <strong>new</strong> IllegalStateException(<span class="string">"Objects are already active"</span>);
<a name="242" href="#242">242</a>         } <strong>else</strong> {
<a name="243" href="#243">243</a>             clear();
<a name="244" href="#244">244</a>             _factory = factory;
<a name="245" href="#245">245</a>         }
<a name="246" href="#246">246</a>     }
<a name="247" href="#247">247</a> 
<a name="248" href="#248">248</a>     <em>/**<em>* The default cap on the number of "sleeping" instances in the pool. */</em></em>
<a name="249" href="#249">249</a>     <strong>protected</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_MAX_SLEEPING  = 8;
<a name="250" href="#250">250</a> 
<a name="251" href="#251">251</a>     <em>/**<em>*</em></em>
<a name="252" href="#252">252</a> <em>     * The default initial size of the pool</em>
<a name="253" href="#253">253</a> <em>     * (this specifies the size of the container, it does not</em>
<a name="254" href="#254">254</a> <em>     * cause the pool to be pre-populated.)</em>
<a name="255" href="#255">255</a> <em>     */</em>
<a name="256" href="#256">256</a>     <strong>protected</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_INIT_SLEEPING_CAPACITY = 4;
<a name="257" href="#257">257</a> 
<a name="258" href="#258">258</a>     <em>/**<em>* My pool. */</em></em>
<a name="259" href="#259">259</a>     <strong>protected</strong> Stack _pool = <strong>null</strong>;
<a name="260" href="#260">260</a> 
<a name="261" href="#261">261</a>     <em>/**<em>* My {@link PoolableObjectFactory}. */</em></em>
<a name="262" href="#262">262</a>     <strong>protected</strong> <a href="../../../../../org/apache/commons/pool/PoolableObjectFactory.html">PoolableObjectFactory</a> _factory = <strong>null</strong>;
<a name="263" href="#263">263</a> 
<a name="264" href="#264">264</a>     <em>/**<em>* The cap on the number of "sleeping" instances in the pool. */</em></em>
<a name="265" href="#265">265</a>     <strong>protected</strong> <strong>int</strong> _maxSleeping = DEFAULT_MAX_SLEEPING;
<a name="266" href="#266">266</a> 
<a name="267" href="#267">267</a>     <em>/**<em>* Number of object borrowed but not yet returned to the pool. */</em></em>
<a name="268" href="#268">268</a>     <strong>protected</strong> <strong>int</strong> _numActive = 0;
<a name="269" href="#269">269</a> }
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