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<FONT color="green">001</FONT> /*<a name="line.1"></a>
<FONT color="green">002</FONT> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<FONT color="green">003</FONT> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a>
<FONT color="green">004</FONT> * distributed with this work for additional information<a name="line.4"></a>
<FONT color="green">005</FONT> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a>
<FONT color="green">006</FONT> * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
<FONT color="green">007</FONT> * "License"); you may not use this file except in compliance<a name="line.7"></a>
<FONT color="green">008</FONT> * with the License. You may obtain a copy of the License at<a name="line.8"></a>
<FONT color="green">009</FONT> *<a name="line.9"></a>
<FONT color="green">010</FONT> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<FONT color="green">011</FONT> *<a name="line.11"></a>
<FONT color="green">012</FONT> * Unless required by applicable law or agreed to in writing,<a name="line.12"></a>
<FONT color="green">013</FONT> * software distributed under the License is distributed on an<a name="line.13"></a>
<FONT color="green">014</FONT> * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY<a name="line.14"></a>
<FONT color="green">015</FONT> * KIND, either express or implied. See the License for the<a name="line.15"></a>
<FONT color="green">016</FONT> * specific language governing permissions and limitations<a name="line.16"></a>
<FONT color="green">017</FONT> * under the License.<a name="line.17"></a>
<FONT color="green">018</FONT> */<a name="line.18"></a>
<FONT color="green">019</FONT> package org.apache.shiro.session.mgt;<a name="line.19"></a>
<FONT color="green">020</FONT> <a name="line.20"></a>
<FONT color="green">021</FONT> import org.apache.shiro.authz.AuthorizationException;<a name="line.21"></a>
<FONT color="green">022</FONT> import org.apache.shiro.session.*;<a name="line.22"></a>
<FONT color="green">023</FONT> import org.apache.shiro.util.CollectionUtils;<a name="line.23"></a>
<FONT color="green">024</FONT> import org.slf4j.Logger;<a name="line.24"></a>
<FONT color="green">025</FONT> import org.slf4j.LoggerFactory;<a name="line.25"></a>
<FONT color="green">026</FONT> <a name="line.26"></a>
<FONT color="green">027</FONT> import java.util.ArrayList;<a name="line.27"></a>
<FONT color="green">028</FONT> import java.util.Collection;<a name="line.28"></a>
<FONT color="green">029</FONT> import java.util.Collections;<a name="line.29"></a>
<FONT color="green">030</FONT> import java.util.Date;<a name="line.30"></a>
<FONT color="green">031</FONT> <a name="line.31"></a>
<FONT color="green">032</FONT> /**<a name="line.32"></a>
<FONT color="green">033</FONT> * Abstract implementation supporting the {@link NativeSessionManager NativeSessionManager} interface, supporting<a name="line.33"></a>
<FONT color="green">034</FONT> * {@link SessionListener SessionListener}s and application of the<a name="line.34"></a>
<FONT color="green">035</FONT> * {@link #getGlobalSessionTimeout() globalSessionTimeout}.<a name="line.35"></a>
<FONT color="green">036</FONT> *<a name="line.36"></a>
<FONT color="green">037</FONT> * @since 1.0<a name="line.37"></a>
<FONT color="green">038</FONT> */<a name="line.38"></a>
<FONT color="green">039</FONT> public abstract class AbstractNativeSessionManager extends AbstractSessionManager implements NativeSessionManager {<a name="line.39"></a>
<FONT color="green">040</FONT> <a name="line.40"></a>
<FONT color="green">041</FONT> private static final Logger log = LoggerFactory.getLogger(AbstractSessionManager.class);<a name="line.41"></a>
<FONT color="green">042</FONT> <a name="line.42"></a>
<FONT color="green">043</FONT> private Collection&lt;SessionListener&gt; listeners;<a name="line.43"></a>
<FONT color="green">044</FONT> <a name="line.44"></a>
<FONT color="green">045</FONT> public AbstractNativeSessionManager() {<a name="line.45"></a>
<FONT color="green">046</FONT> this.listeners = new ArrayList&lt;SessionListener&gt;();<a name="line.46"></a>
<FONT color="green">047</FONT> }<a name="line.47"></a>
<FONT color="green">048</FONT> <a name="line.48"></a>
<FONT color="green">049</FONT> public void setSessionListeners(Collection&lt;SessionListener&gt; listeners) {<a name="line.49"></a>
<FONT color="green">050</FONT> this.listeners = listeners != null ? listeners : new ArrayList&lt;SessionListener&gt;();<a name="line.50"></a>
<FONT color="green">051</FONT> }<a name="line.51"></a>
<FONT color="green">052</FONT> <a name="line.52"></a>
<FONT color="green">053</FONT> @SuppressWarnings({"UnusedDeclaration"})<a name="line.53"></a>
<FONT color="green">054</FONT> public Collection&lt;SessionListener&gt; getSessionListeners() {<a name="line.54"></a>
<FONT color="green">055</FONT> return this.listeners;<a name="line.55"></a>
<FONT color="green">056</FONT> }<a name="line.56"></a>
<FONT color="green">057</FONT> <a name="line.57"></a>
<FONT color="green">058</FONT> public Session start(SessionContext context) {<a name="line.58"></a>
<FONT color="green">059</FONT> Session session = createSession(context);<a name="line.59"></a>
<FONT color="green">060</FONT> applyGlobalSessionTimeout(session);<a name="line.60"></a>
<FONT color="green">061</FONT> onStart(session, context);<a name="line.61"></a>
<FONT color="green">062</FONT> notifyStart(session);<a name="line.62"></a>
<FONT color="green">063</FONT> //Don't expose the EIS-tier Session object to the client-tier:<a name="line.63"></a>
<FONT color="green">064</FONT> return createExposedSession(session, context);<a name="line.64"></a>
<FONT color="green">065</FONT> }<a name="line.65"></a>
<FONT color="green">066</FONT> <a name="line.66"></a>
<FONT color="green">067</FONT> /**<a name="line.67"></a>
<FONT color="green">068</FONT> * Creates a new {@code Session Session} instance based on the specified (possibly {@code null})<a name="line.68"></a>
<FONT color="green">069</FONT> * initialization data. Implementing classes must manage the persistent state of the returned session such that it<a name="line.69"></a>
<FONT color="green">070</FONT> * could later be acquired via the {@link #getSession(SessionKey)} method.<a name="line.70"></a>
<FONT color="green">071</FONT> *<a name="line.71"></a>
<FONT color="green">072</FONT> * @param context the initialization data that can be used by the implementation or underlying<a name="line.72"></a>
<FONT color="green">073</FONT> * {@link SessionFactory} when instantiating the internal {@code Session} instance.<a name="line.73"></a>
<FONT color="green">074</FONT> * @return the new {@code Session} instance.<a name="line.74"></a>
<FONT color="green">075</FONT> * @throws org.apache.shiro.authz.HostUnauthorizedException<a name="line.75"></a>
<FONT color="green">076</FONT> * if the system access control policy restricts access based<a name="line.76"></a>
<FONT color="green">077</FONT> * on client location/IP and the specified hostAddress hasn't been enabled.<a name="line.77"></a>
<FONT color="green">078</FONT> * @throws AuthorizationException if the system access control policy does not allow the currently executing<a name="line.78"></a>
<FONT color="green">079</FONT> * caller to start sessions.<a name="line.79"></a>
<FONT color="green">080</FONT> */<a name="line.80"></a>
<FONT color="green">081</FONT> protected abstract Session createSession(SessionContext context) throws AuthorizationException;<a name="line.81"></a>
<FONT color="green">082</FONT> <a name="line.82"></a>
<FONT color="green">083</FONT> protected void applyGlobalSessionTimeout(Session session) {<a name="line.83"></a>
<FONT color="green">084</FONT> session.setTimeout(getGlobalSessionTimeout());<a name="line.84"></a>
<FONT color="green">085</FONT> onChange(session);<a name="line.85"></a>
<FONT color="green">086</FONT> }<a name="line.86"></a>
<FONT color="green">087</FONT> <a name="line.87"></a>
<FONT color="green">088</FONT> /**<a name="line.88"></a>
<FONT color="green">089</FONT> * Template method that allows subclasses to react to a new session being created.<a name="line.89"></a>
<FONT color="green">090</FONT> * &lt;p/&gt;<a name="line.90"></a>
<FONT color="green">091</FONT> * This method is invoked &lt;em&gt;before&lt;/em&gt; any session listeners are notified.<a name="line.91"></a>
<FONT color="green">092</FONT> *<a name="line.92"></a>
<FONT color="green">093</FONT> * @param session the session that was just {@link #createSession created}.<a name="line.93"></a>
<FONT color="green">094</FONT> * @param context the {@link SessionContext SessionContext} that was used to start the session.<a name="line.94"></a>
<FONT color="green">095</FONT> */<a name="line.95"></a>
<FONT color="green">096</FONT> protected void onStart(Session session, SessionContext context) {<a name="line.96"></a>
<FONT color="green">097</FONT> }<a name="line.97"></a>
<FONT color="green">098</FONT> <a name="line.98"></a>
<FONT color="green">099</FONT> public Session getSession(SessionKey key) throws SessionException {<a name="line.99"></a>
<FONT color="green">100</FONT> Session session = lookupSession(key);<a name="line.100"></a>
<FONT color="green">101</FONT> return session != null ? createExposedSession(session, key) : null;<a name="line.101"></a>
<FONT color="green">102</FONT> }<a name="line.102"></a>
<FONT color="green">103</FONT> <a name="line.103"></a>
<FONT color="green">104</FONT> private Session lookupSession(SessionKey key) throws SessionException {<a name="line.104"></a>
<FONT color="green">105</FONT> if (key == null) {<a name="line.105"></a>
<FONT color="green">106</FONT> throw new NullPointerException("SessionKey argument cannot be null.");<a name="line.106"></a>
<FONT color="green">107</FONT> }<a name="line.107"></a>
<FONT color="green">108</FONT> return doGetSession(key);<a name="line.108"></a>
<FONT color="green">109</FONT> }<a name="line.109"></a>
<FONT color="green">110</FONT> <a name="line.110"></a>
<FONT color="green">111</FONT> private Session lookupRequiredSession(SessionKey key) throws SessionException {<a name="line.111"></a>
<FONT color="green">112</FONT> Session session = lookupSession(key);<a name="line.112"></a>
<FONT color="green">113</FONT> if (session == null) {<a name="line.113"></a>
<FONT color="green">114</FONT> String msg = "Unable to locate required Session instance based on SessionKey [" + key + "].";<a name="line.114"></a>
<FONT color="green">115</FONT> throw new UnknownSessionException(msg);<a name="line.115"></a>
<FONT color="green">116</FONT> }<a name="line.116"></a>
<FONT color="green">117</FONT> return session;<a name="line.117"></a>
<FONT color="green">118</FONT> }<a name="line.118"></a>
<FONT color="green">119</FONT> <a name="line.119"></a>
<FONT color="green">120</FONT> protected abstract Session doGetSession(SessionKey key) throws InvalidSessionException;<a name="line.120"></a>
<FONT color="green">121</FONT> <a name="line.121"></a>
<FONT color="green">122</FONT> protected Session createExposedSession(Session session, SessionContext context) {<a name="line.122"></a>
<FONT color="green">123</FONT> return new DelegatingSession(this, new DefaultSessionKey(session.getId()));<a name="line.123"></a>
<FONT color="green">124</FONT> }<a name="line.124"></a>
<FONT color="green">125</FONT> <a name="line.125"></a>
<FONT color="green">126</FONT> protected Session createExposedSession(Session session, SessionKey key) {<a name="line.126"></a>
<FONT color="green">127</FONT> return new DelegatingSession(this, new DefaultSessionKey(session.getId()));<a name="line.127"></a>
<FONT color="green">128</FONT> }<a name="line.128"></a>
<FONT color="green">129</FONT> <a name="line.129"></a>
<FONT color="green">130</FONT> /**<a name="line.130"></a>
<FONT color="green">131</FONT> * Returns the session instance to use to pass to registered {@code SessionListener}s for notification<a name="line.131"></a>
<FONT color="green">132</FONT> * that the session has been invalidated (stopped or expired).<a name="line.132"></a>
<FONT color="green">133</FONT> * &lt;p/&gt;<a name="line.133"></a>
<FONT color="green">134</FONT> * The default implementation returns an {@link ImmutableProxiedSession ImmutableProxiedSession} instance to ensure<a name="line.134"></a>
<FONT color="green">135</FONT> * that the specified {@code session} argument is not modified by any listeners.<a name="line.135"></a>
<FONT color="green">136</FONT> *<a name="line.136"></a>
<FONT color="green">137</FONT> * @param session the {@code Session} object being invalidated.<a name="line.137"></a>
<FONT color="green">138</FONT> * @return the {@code Session} instance to use to pass to registered {@code SessionListener}s for notification.<a name="line.138"></a>
<FONT color="green">139</FONT> */<a name="line.139"></a>
<FONT color="green">140</FONT> protected Session beforeInvalidNotification(Session session) {<a name="line.140"></a>
<FONT color="green">141</FONT> return new ImmutableProxiedSession(session);<a name="line.141"></a>
<FONT color="green">142</FONT> }<a name="line.142"></a>
<FONT color="green">143</FONT> <a name="line.143"></a>
<FONT color="green">144</FONT> /**<a name="line.144"></a>
<FONT color="green">145</FONT> * Notifies any interested {@link SessionListener}s that a Session has started. This method is invoked<a name="line.145"></a>
<FONT color="green">146</FONT> * &lt;em&gt;after&lt;/em&gt; the {@link #onStart onStart} method is called.<a name="line.146"></a>
<FONT color="green">147</FONT> *<a name="line.147"></a>
<FONT color="green">148</FONT> * @param session the session that has just started that will be delivered to any<a name="line.148"></a>
<FONT color="green">149</FONT> * {@link #setSessionListeners(java.util.Collection) registered} session listeners.<a name="line.149"></a>
<FONT color="green">150</FONT> * @see SessionListener#onStart(org.apache.shiro.session.Session)<a name="line.150"></a>
<FONT color="green">151</FONT> */<a name="line.151"></a>
<FONT color="green">152</FONT> protected void notifyStart(Session session) {<a name="line.152"></a>
<FONT color="green">153</FONT> for (SessionListener listener : this.listeners) {<a name="line.153"></a>
<FONT color="green">154</FONT> listener.onStart(session);<a name="line.154"></a>
<FONT color="green">155</FONT> }<a name="line.155"></a>
<FONT color="green">156</FONT> }<a name="line.156"></a>
<FONT color="green">157</FONT> <a name="line.157"></a>
<FONT color="green">158</FONT> protected void notifyStop(Session session) {<a name="line.158"></a>
<FONT color="green">159</FONT> Session forNotification = beforeInvalidNotification(session);<a name="line.159"></a>
<FONT color="green">160</FONT> for (SessionListener listener : this.listeners) {<a name="line.160"></a>
<FONT color="green">161</FONT> listener.onStop(forNotification);<a name="line.161"></a>
<FONT color="green">162</FONT> }<a name="line.162"></a>
<FONT color="green">163</FONT> }<a name="line.163"></a>
<FONT color="green">164</FONT> <a name="line.164"></a>
<FONT color="green">165</FONT> protected void notifyExpiration(Session session) {<a name="line.165"></a>
<FONT color="green">166</FONT> Session forNotification = beforeInvalidNotification(session);<a name="line.166"></a>
<FONT color="green">167</FONT> for (SessionListener listener : this.listeners) {<a name="line.167"></a>
<FONT color="green">168</FONT> listener.onExpiration(forNotification);<a name="line.168"></a>
<FONT color="green">169</FONT> }<a name="line.169"></a>
<FONT color="green">170</FONT> }<a name="line.170"></a>
<FONT color="green">171</FONT> <a name="line.171"></a>
<FONT color="green">172</FONT> public Date getStartTimestamp(SessionKey key) {<a name="line.172"></a>
<FONT color="green">173</FONT> return lookupRequiredSession(key).getStartTimestamp();<a name="line.173"></a>
<FONT color="green">174</FONT> }<a name="line.174"></a>
<FONT color="green">175</FONT> <a name="line.175"></a>
<FONT color="green">176</FONT> public Date getLastAccessTime(SessionKey key) {<a name="line.176"></a>
<FONT color="green">177</FONT> return lookupRequiredSession(key).getLastAccessTime();<a name="line.177"></a>
<FONT color="green">178</FONT> }<a name="line.178"></a>
<FONT color="green">179</FONT> <a name="line.179"></a>
<FONT color="green">180</FONT> public long getTimeout(SessionKey key) throws InvalidSessionException {<a name="line.180"></a>
<FONT color="green">181</FONT> return lookupRequiredSession(key).getTimeout();<a name="line.181"></a>
<FONT color="green">182</FONT> }<a name="line.182"></a>
<FONT color="green">183</FONT> <a name="line.183"></a>
<FONT color="green">184</FONT> public void setTimeout(SessionKey key, long maxIdleTimeInMillis) throws InvalidSessionException {<a name="line.184"></a>
<FONT color="green">185</FONT> Session s = lookupRequiredSession(key);<a name="line.185"></a>
<FONT color="green">186</FONT> s.setTimeout(maxIdleTimeInMillis);<a name="line.186"></a>
<FONT color="green">187</FONT> onChange(s);<a name="line.187"></a>
<FONT color="green">188</FONT> }<a name="line.188"></a>
<FONT color="green">189</FONT> <a name="line.189"></a>
<FONT color="green">190</FONT> public void touch(SessionKey key) throws InvalidSessionException {<a name="line.190"></a>
<FONT color="green">191</FONT> Session s = lookupRequiredSession(key);<a name="line.191"></a>
<FONT color="green">192</FONT> s.touch();<a name="line.192"></a>
<FONT color="green">193</FONT> onChange(s);<a name="line.193"></a>
<FONT color="green">194</FONT> }<a name="line.194"></a>
<FONT color="green">195</FONT> <a name="line.195"></a>
<FONT color="green">196</FONT> public String getHost(SessionKey key) {<a name="line.196"></a>
<FONT color="green">197</FONT> return lookupRequiredSession(key).getHost();<a name="line.197"></a>
<FONT color="green">198</FONT> }<a name="line.198"></a>
<FONT color="green">199</FONT> <a name="line.199"></a>
<FONT color="green">200</FONT> public Collection&lt;Object&gt; getAttributeKeys(SessionKey key) {<a name="line.200"></a>
<FONT color="green">201</FONT> Collection&lt;Object&gt; c = lookupRequiredSession(key).getAttributeKeys();<a name="line.201"></a>
<FONT color="green">202</FONT> if (!CollectionUtils.isEmpty(c)) {<a name="line.202"></a>
<FONT color="green">203</FONT> return Collections.unmodifiableCollection(c);<a name="line.203"></a>
<FONT color="green">204</FONT> }<a name="line.204"></a>
<FONT color="green">205</FONT> return Collections.emptySet();<a name="line.205"></a>
<FONT color="green">206</FONT> }<a name="line.206"></a>
<FONT color="green">207</FONT> <a name="line.207"></a>
<FONT color="green">208</FONT> public Object getAttribute(SessionKey sessionKey, Object attributeKey) throws InvalidSessionException {<a name="line.208"></a>
<FONT color="green">209</FONT> return lookupRequiredSession(sessionKey).getAttribute(attributeKey);<a name="line.209"></a>
<FONT color="green">210</FONT> }<a name="line.210"></a>
<FONT color="green">211</FONT> <a name="line.211"></a>
<FONT color="green">212</FONT> public void setAttribute(SessionKey sessionKey, Object attributeKey, Object value) throws InvalidSessionException {<a name="line.212"></a>
<FONT color="green">213</FONT> if (value == null) {<a name="line.213"></a>
<FONT color="green">214</FONT> removeAttribute(sessionKey, attributeKey);<a name="line.214"></a>
<FONT color="green">215</FONT> } else {<a name="line.215"></a>
<FONT color="green">216</FONT> Session s = lookupRequiredSession(sessionKey);<a name="line.216"></a>
<FONT color="green">217</FONT> s.setAttribute(attributeKey, value);<a name="line.217"></a>
<FONT color="green">218</FONT> onChange(s);<a name="line.218"></a>
<FONT color="green">219</FONT> }<a name="line.219"></a>
<FONT color="green">220</FONT> }<a name="line.220"></a>
<FONT color="green">221</FONT> <a name="line.221"></a>
<FONT color="green">222</FONT> public Object removeAttribute(SessionKey sessionKey, Object attributeKey) throws InvalidSessionException {<a name="line.222"></a>
<FONT color="green">223</FONT> Session s = lookupRequiredSession(sessionKey);<a name="line.223"></a>
<FONT color="green">224</FONT> Object removed = s.removeAttribute(attributeKey);<a name="line.224"></a>
<FONT color="green">225</FONT> if (removed != null) {<a name="line.225"></a>
<FONT color="green">226</FONT> onChange(s);<a name="line.226"></a>
<FONT color="green">227</FONT> }<a name="line.227"></a>
<FONT color="green">228</FONT> return removed;<a name="line.228"></a>
<FONT color="green">229</FONT> }<a name="line.229"></a>
<FONT color="green">230</FONT> <a name="line.230"></a>
<FONT color="green">231</FONT> public boolean isValid(SessionKey key) {<a name="line.231"></a>
<FONT color="green">232</FONT> try {<a name="line.232"></a>
<FONT color="green">233</FONT> checkValid(key);<a name="line.233"></a>
<FONT color="green">234</FONT> return true;<a name="line.234"></a>
<FONT color="green">235</FONT> } catch (InvalidSessionException e) {<a name="line.235"></a>
<FONT color="green">236</FONT> return false;<a name="line.236"></a>
<FONT color="green">237</FONT> }<a name="line.237"></a>
<FONT color="green">238</FONT> }<a name="line.238"></a>
<FONT color="green">239</FONT> <a name="line.239"></a>
<FONT color="green">240</FONT> public void stop(SessionKey key) throws InvalidSessionException {<a name="line.240"></a>
<FONT color="green">241</FONT> Session session = lookupRequiredSession(key);<a name="line.241"></a>
<FONT color="green">242</FONT> try {<a name="line.242"></a>
<FONT color="green">243</FONT> if (log.isDebugEnabled()) {<a name="line.243"></a>
<FONT color="green">244</FONT> log.debug("Stopping session with id [" + session.getId() + "]");<a name="line.244"></a>
<FONT color="green">245</FONT> }<a name="line.245"></a>
<FONT color="green">246</FONT> session.stop();<a name="line.246"></a>
<FONT color="green">247</FONT> onStop(session, key);<a name="line.247"></a>
<FONT color="green">248</FONT> notifyStop(session);<a name="line.248"></a>
<FONT color="green">249</FONT> } finally {<a name="line.249"></a>
<FONT color="green">250</FONT> afterStopped(session);<a name="line.250"></a>
<FONT color="green">251</FONT> }<a name="line.251"></a>
<FONT color="green">252</FONT> }<a name="line.252"></a>
<FONT color="green">253</FONT> <a name="line.253"></a>
<FONT color="green">254</FONT> protected void onStop(Session session, SessionKey key) {<a name="line.254"></a>
<FONT color="green">255</FONT> onStop(session);<a name="line.255"></a>
<FONT color="green">256</FONT> }<a name="line.256"></a>
<FONT color="green">257</FONT> <a name="line.257"></a>
<FONT color="green">258</FONT> protected void onStop(Session session) {<a name="line.258"></a>
<FONT color="green">259</FONT> onChange(session);<a name="line.259"></a>
<FONT color="green">260</FONT> }<a name="line.260"></a>
<FONT color="green">261</FONT> <a name="line.261"></a>
<FONT color="green">262</FONT> protected void afterStopped(Session session) {<a name="line.262"></a>
<FONT color="green">263</FONT> }<a name="line.263"></a>
<FONT color="green">264</FONT> <a name="line.264"></a>
<FONT color="green">265</FONT> public void checkValid(SessionKey key) throws InvalidSessionException {<a name="line.265"></a>
<FONT color="green">266</FONT> //just try to acquire it. If there is a problem, an exception will be thrown:<a name="line.266"></a>
<FONT color="green">267</FONT> lookupRequiredSession(key);<a name="line.267"></a>
<FONT color="green">268</FONT> }<a name="line.268"></a>
<FONT color="green">269</FONT> <a name="line.269"></a>
<FONT color="green">270</FONT> protected void onChange(Session s) {<a name="line.270"></a>
<FONT color="green">271</FONT> }<a name="line.271"></a>
<FONT color="green">272</FONT> }<a name="line.272"></a>
</PRE>
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