genericobjectpool.html

用JAVA编写的,在做实验的时候留下来的,本来想删的,但是传上来,大家分享吧

<a name="123" href="#123">123</a> <em> * @see GenericKeyedObjectPool</em>
<a name="124" href="#124">124</a> <em> * @author Rodney Waldhoff</em>
<a name="125" href="#125">125</a> <em> * @author Dirk Verbeeck</em>
<a name="126" href="#126">126</a> <em> * @version $Revision: 1.2 $ $Date: 2006/05/16 01:31:42 $</em>
<a name="127" href="#127">127</a> <em> */</em>
<a name="128" href="#128">128</a> <strong>public</strong> <strong>class</strong> <a href="../../../../../org/apache/commons/pool/impl/GenericObjectPool.html">GenericObjectPool</a> <strong>extends</strong> BaseObjectPool implements ObjectPool {
<a name="129" href="#129">129</a> 
<a name="130" href="#130">130</a>     <em class="comment">//--- public constants -------------------------------------------</em>
<a name="131" href="#131">131</a> 
<a name="132" href="#132">132</a>     <em>/**<em>*</em></em>
<a name="133" href="#133">133</a> <em>     * A "when exhausted action" type indicating that when the pool is</em>
<a name="134" href="#134">134</a> <em>     * exhausted (i.e., the maximum number of active objects has</em>
<a name="135" href="#135">135</a> <em>     * been reached), the {@link #borrowObject}</em>
<a name="136" href="#136">136</a> <em>     * method should fail, throwing a {@link NoSuchElementException}.</em>
<a name="137" href="#137">137</a> <em>     * @see #WHEN_EXHAUSTED_BLOCK</em>
<a name="138" href="#138">138</a> <em>     * @see #WHEN_EXHAUSTED_GROW</em>
<a name="139" href="#139">139</a> <em>     * @see #setWhenExhaustedAction</em>
<a name="140" href="#140">140</a> <em>     */</em>
<a name="141" href="#141">141</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> byte WHEN_EXHAUSTED_FAIL   = 0;
<a name="142" href="#142">142</a> 
<a name="143" href="#143">143</a>     <em>/**<em>*</em></em>
<a name="144" href="#144">144</a> <em>     * A "when exhausted action" type indicating that when the pool</em>
<a name="145" href="#145">145</a> <em>     * is exhausted (i.e., the maximum number</em>
<a name="146" href="#146">146</a> <em>     * of active objects has been reached), the {@link #borrowObject}</em>
<a name="147" href="#147">147</a> <em>     * method should block until a new object is available, or the</em>
<a name="148" href="#148">148</a> <em>     * {@link #getMaxWait maximum wait time} has been reached.</em>
<a name="149" href="#149">149</a> <em>     * @see #WHEN_EXHAUSTED_FAIL</em>
<a name="150" href="#150">150</a> <em>     * @see #WHEN_EXHAUSTED_GROW</em>
<a name="151" href="#151">151</a> <em>     * @see #setMaxWait</em>
<a name="152" href="#152">152</a> <em>     * @see #getMaxWait</em>
<a name="153" href="#153">153</a> <em>     * @see #setWhenExhaustedAction</em>
<a name="154" href="#154">154</a> <em>     */</em>
<a name="155" href="#155">155</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> byte WHEN_EXHAUSTED_BLOCK  = 1;
<a name="156" href="#156">156</a> 
<a name="157" href="#157">157</a>     <em>/**<em>*</em></em>
<a name="158" href="#158">158</a> <em>     * A "when exhausted action" type indicating that when the pool is</em>
<a name="159" href="#159">159</a> <em>     * exhausted (i.e., the maximum number</em>
<a name="160" href="#160">160</a> <em>     * of active objects has been reached), the {@link #borrowObject}</em>
<a name="161" href="#161">161</a> <em>     * method should simply create a new object anyway.</em>
<a name="162" href="#162">162</a> <em>     * @see #WHEN_EXHAUSTED_FAIL</em>
<a name="163" href="#163">163</a> <em>     * @see #WHEN_EXHAUSTED_GROW</em>
<a name="164" href="#164">164</a> <em>     * @see #setWhenExhaustedAction</em>
<a name="165" href="#165">165</a> <em>     */</em>
<a name="166" href="#166">166</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> byte WHEN_EXHAUSTED_GROW   = 2;
<a name="167" href="#167">167</a> 
<a name="168" href="#168">168</a>     <em>/**<em>*</em></em>
<a name="169" href="#169">169</a> <em>     * The default cap on the number of "sleeping" instances in the pool.</em>
<a name="170" href="#170">170</a> <em>     * @see #getMaxIdle</em>
<a name="171" href="#171">171</a> <em>     * @see #setMaxIdle</em>
<a name="172" href="#172">172</a> <em>     */</em>
<a name="173" href="#173">173</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_MAX_IDLE  = 8;
<a name="174" href="#174">174</a> 
<a name="175" href="#175">175</a>     <em>/**<em>*</em></em>
<a name="176" href="#176">176</a> <em>     * The default minimum number of "sleeping" instances in the pool</em>
<a name="177" href="#177">177</a> <em>     * before before the evictor thread (if active) spawns new objects.</em>
<a name="178" href="#178">178</a> <em>     * @see #getMinIdle</em>
<a name="179" href="#179">179</a> <em>     * @see #setMinIdle</em>
<a name="180" href="#180">180</a> <em>     */</em>
<a name="181" href="#181">181</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_MIN_IDLE = 0;
<a name="182" href="#182">182</a> 
<a name="183" href="#183">183</a>     <em>/**<em>*</em></em>
<a name="184" href="#184">184</a> <em>     * The default cap on the total number of active instances from the pool.</em>
<a name="185" href="#185">185</a> <em>     * @see #getMaxActive</em>
<a name="186" href="#186">186</a> <em>     */</em>
<a name="187" href="#187">187</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_MAX_ACTIVE  = 8;
<a name="188" href="#188">188</a> 
<a name="189" href="#189">189</a>     <em>/**<em>*</em></em>
<a name="190" href="#190">190</a> <em>     * The default "when exhausted action" for the pool.</em>
<a name="191" href="#191">191</a> <em>     * @see #WHEN_EXHAUSTED_BLOCK</em>
<a name="192" href="#192">192</a> <em>     * @see #WHEN_EXHAUSTED_FAIL</em>
<a name="193" href="#193">193</a> <em>     * @see #WHEN_EXHAUSTED_GROW</em>
<a name="194" href="#194">194</a> <em>     * @see #setWhenExhaustedAction</em>
<a name="195" href="#195">195</a> <em>     */</em>
<a name="196" href="#196">196</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> byte DEFAULT_WHEN_EXHAUSTED_ACTION = WHEN_EXHAUSTED_BLOCK;
<a name="197" href="#197">197</a> 
<a name="198" href="#198">198</a>     <em>/**<em>*</em></em>
<a name="199" href="#199">199</a> <em>     * The default maximum amount of time (in millis) the</em>
<a name="200" href="#200">200</a> <em>     * {@link #borrowObject} method should block before throwing</em>
<a name="201" href="#201">201</a> <em>     * an exception when the pool is exhausted and the</em>
<a name="202" href="#202">202</a> <em>     * {@link #getWhenExhaustedAction "when exhausted" action} is</em>
<a name="203" href="#203">203</a> <em>     * {@link #WHEN_EXHAUSTED_BLOCK}.</em>
<a name="204" href="#204">204</a> <em>     * @see #getMaxWait</em>
<a name="205" href="#205">205</a> <em>     * @see #setMaxWait</em>
<a name="206" href="#206">206</a> <em>     */</em>
<a name="207" href="#207">207</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>long</strong> DEFAULT_MAX_WAIT = -1L;
<a name="208" href="#208">208</a> 
<a name="209" href="#209">209</a>     <em>/**<em>*</em></em>
<a name="210" href="#210">210</a> <em>     * The default "test on borrow" value.</em>
<a name="211" href="#211">211</a> <em>     * @see #getTestOnBorrow</em>
<a name="212" href="#212">212</a> <em>     * @see #setTestOnBorrow</em>
<a name="213" href="#213">213</a> <em>     */</em>
<a name="214" href="#214">214</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>boolean</strong> DEFAULT_TEST_ON_BORROW = false;
<a name="215" href="#215">215</a> 
<a name="216" href="#216">216</a>     <em>/**<em>*</em></em>
<a name="217" href="#217">217</a> <em>     * The default "test on return" value.</em>
<a name="218" href="#218">218</a> <em>     * @see #getTestOnReturn</em>
<a name="219" href="#219">219</a> <em>     * @see #setTestOnReturn</em>
<a name="220" href="#220">220</a> <em>     */</em>
<a name="221" href="#221">221</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>boolean</strong> DEFAULT_TEST_ON_RETURN = false;
<a name="222" href="#222">222</a> 
<a name="223" href="#223">223</a>     <em>/**<em>*</em></em>
<a name="224" href="#224">224</a> <em>     * The default "test while idle" value.</em>
<a name="225" href="#225">225</a> <em>     * @see #getTestWhileIdle</em>
<a name="226" href="#226">226</a> <em>     * @see #setTestWhileIdle</em>
<a name="227" href="#227">227</a> <em>     * @see #getTimeBetweenEvictionRunsMillis</em>
<a name="228" href="#228">228</a> <em>     * @see #setTimeBetweenEvictionRunsMillis</em>
<a name="229" href="#229">229</a> <em>     */</em>
<a name="230" href="#230">230</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>boolean</strong> DEFAULT_TEST_WHILE_IDLE = false;
<a name="231" href="#231">231</a> 
<a name="232" href="#232">232</a>     <em>/**<em>*</em></em>
<a name="233" href="#233">233</a> <em>     * The default "time between eviction runs" value.</em>
<a name="234" href="#234">234</a> <em>     * @see #getTimeBetweenEvictionRunsMillis</em>
<a name="235" href="#235">235</a> <em>     * @see #setTimeBetweenEvictionRunsMillis</em>
<a name="236" href="#236">236</a> <em>     */</em>
<a name="237" href="#237">237</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>long</strong> DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS = -1L;
<a name="238" href="#238">238</a> 
<a name="239" href="#239">239</a>     <em>/**<em>*</em></em>
<a name="240" href="#240">240</a> <em>     * The default number of objects to examine per run in the</em>
<a name="241" href="#241">241</a> <em>     * idle object evictor.</em>
<a name="242" href="#242">242</a> <em>     * @see #getNumTestsPerEvictionRun</em>
<a name="243" href="#243">243</a> <em>     * @see #setNumTestsPerEvictionRun</em>
<a name="244" href="#244">244</a> <em>     * @see #getTimeBetweenEvictionRunsMillis</em>
<a name="245" href="#245">245</a> <em>     * @see #setTimeBetweenEvictionRunsMillis</em>
<a name="246" href="#246">246</a> <em>     */</em>
<a name="247" href="#247">247</a>     <strong>public</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_NUM_TESTS_PER_EVICTION_RUN = 3;
<a name="248" href="#248">248</a> 
<a name="249" href="#249">249</a>     <em>/**<em>*</em></em>
<a name="250" href="#250">250</a> <em>     * The default value for {@link #getMinEvictableIdleTimeMillis}.</em>
<a name="251" href="#251">251</a> <em>     * @see #getMinEvictableIdleTimeMillis</em>
<a name="252" href="#252">252</a> <em>     * @see #setMinEvictableIdleTimeMillis</em>
<a name="253" href="#253">253</a> <em>     */</em>