softreferenceobjectpool.html

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<a name="93" href="#93">93</a>              } <strong>catch</strong>(Exception e) {
<a name="94" href="#94">94</a>                  success = false;
<a name="95" href="#95">95</a>              }
<a name="96" href="#96">96</a>          }
<a name="97" href="#97">97</a>  
<a name="98" href="#98">98</a>          <strong>boolean</strong> shouldDestroy = !success;
<a name="99" href="#99">99</a>          _numActive--;
<a name="100" href="#100">100</a>         <strong>if</strong>(success) {
<a name="101" href="#101">101</a>             _pool.add(<strong>new</strong> SoftReference(obj));
<a name="102" href="#102">102</a>         }
<a name="103" href="#103">103</a>         notifyAll(); <em class="comment">// _numActive has changed</em>
<a name="104" href="#104">104</a> 
<a name="105" href="#105">105</a>         <strong>if</strong>(shouldDestroy) {
<a name="106" href="#106">106</a>             <strong>try</strong> {
<a name="107" href="#107">107</a>                 _factory.destroyObject(obj);
<a name="108" href="#108">108</a>             } <strong>catch</strong>(Exception e) {
<a name="109" href="#109">109</a>                 <em class="comment">// ignored</em>
<a name="110" href="#110">110</a>             }
<a name="111" href="#111">111</a>         }
<a name="112" href="#112">112</a> 
<a name="113" href="#113">113</a>     }
<a name="114" href="#114">114</a> 
<a name="115" href="#115">115</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> invalidateObject(Object obj) throws Exception {
<a name="116" href="#116">116</a>         assertOpen();
<a name="117" href="#117">117</a>         _numActive--;
<a name="118" href="#118">118</a>         _factory.destroyObject(obj);
<a name="119" href="#119">119</a>         notifyAll(); <em class="comment">// _numActive has changed</em>
<a name="120" href="#120">120</a>     }
<a name="121" href="#121">121</a> 
<a name="122" href="#122">122</a>     <em>/**<em>*</em></em>
<a name="123" href="#123">123</a> <em>     * Create an object, and place it into the pool.</em>
<a name="124" href="#124">124</a> <em>     * addObject() is useful for "pre-loading" a pool with idle objects.</em>
<a name="125" href="#125">125</a> <em>     */</em>
<a name="126" href="#126">126</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> addObject() throws Exception {
<a name="127" href="#127">127</a>         assertOpen();
<a name="128" href="#128">128</a>         Object obj = _factory.makeObject();
<a name="129" href="#129">129</a>         _numActive++;   <em class="comment">// A little slimy - must do this because returnObject decrements it.</em>
<a name="130" href="#130">130</a>         returnObject(obj);
<a name="131" href="#131">131</a>     }
<a name="132" href="#132">132</a> 
<a name="133" href="#133">133</a>     <em>/**<em>* Returns an approximation not less than the of the number of idle instances in the pool. */</em></em>
<a name="134" href="#134">134</a>     <strong>public</strong> <strong>synchronized</strong> <strong>int</strong> getNumIdle() {
<a name="135" href="#135">135</a>         assertOpen();
<a name="136" href="#136">136</a>         <strong>return</strong> _pool.size();
<a name="137" href="#137">137</a>     }
<a name="138" href="#138">138</a> 
<a name="139" href="#139">139</a>     <strong>public</strong> <strong>synchronized</strong> <strong>int</strong> getNumActive() {
<a name="140" href="#140">140</a>         assertOpen();
<a name="141" href="#141">141</a>         <strong>return</strong> _numActive;
<a name="142" href="#142">142</a>     }
<a name="143" href="#143">143</a> 
<a name="144" href="#144">144</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> clear() {
<a name="145" href="#145">145</a>         assertOpen();
<a name="146" href="#146">146</a>         <strong>if</strong>(<strong>null</strong> != _factory) {
<a name="147" href="#147">147</a>             Iterator iter = _pool.iterator();
<a name="148" href="#148">148</a>             <strong>while</strong>(iter.hasNext()) {
<a name="149" href="#149">149</a>                 <strong>try</strong> {
<a name="150" href="#150">150</a>                     Object obj = ((SoftReference)iter.next()).get();
<a name="151" href="#151">151</a>                     <strong>if</strong>(<strong>null</strong> != obj) {
<a name="152" href="#152">152</a>                         _factory.destroyObject(obj);
<a name="153" href="#153">153</a>                     }
<a name="154" href="#154">154</a>                 } <strong>catch</strong>(Exception e) {
<a name="155" href="#155">155</a>                     <em class="comment">// ignore error, keep destroying the rest</em>
<a name="156" href="#156">156</a>                 }
<a name="157" href="#157">157</a>             }
<a name="158" href="#158">158</a>         }
<a name="159" href="#159">159</a>         _pool.clear();
<a name="160" href="#160">160</a>     }
<a name="161" href="#161">161</a> 
<a name="162" href="#162">162</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> close() throws Exception {
<a name="163" href="#163">163</a>         clear();
<a name="164" href="#164">164</a>         _pool = <strong>null</strong>;
<a name="165" href="#165">165</a>         _factory = <strong>null</strong>;
<a name="166" href="#166">166</a>         <strong>super</strong>.close();
<a name="167" href="#167">167</a>     }
<a name="168" href="#168">168</a> 
<a name="169" href="#169">169</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="170" href="#170">170</a>         assertOpen();
<a name="171" href="#171">171</a>         <strong>if</strong>(0 &lt; getNumActive()) {
<a name="172" href="#172">172</a>             <strong>throw</strong> <strong>new</strong> IllegalStateException(<span class="string">"Objects are already active"</span>);
<a name="173" href="#173">173</a>         } <strong>else</strong> {
<a name="174" href="#174">174</a>             clear();
<a name="175" href="#175">175</a>             _factory = factory;
<a name="176" href="#176">176</a>         }
<a name="177" href="#177">177</a>     }
<a name="178" href="#178">178</a> 
<a name="179" href="#179">179</a>     <em>/**<em>* My pool. */</em></em>
<a name="180" href="#180">180</a>     <strong>private</strong> List _pool = <strong>null</strong>;
<a name="181" href="#181">181</a> 
<a name="182" href="#182">182</a>     <em>/**<em>* My {@link PoolableObjectFactory}. */</em></em>
<a name="183" href="#183">183</a>     <strong>private</strong> <a href="../../../../../org/apache/commons/pool/PoolableObjectFactory.html">PoolableObjectFactory</a> _factory = <strong>null</strong>;
<a name="184" href="#184">184</a> 
<a name="185" href="#185">185</a>     <em>/**<em>* Number of active objects. */</em></em>
<a name="186" href="#186">186</a>     <strong>private</strong> <strong>int</strong> _numActive = 0;
<a name="187" href="#187">187</a> }
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