UserContext.java<TITLE> <LINK rel="stylesheet" href="../..//java.css" type="text/css" media="all" /> </HEAD> <BODY id="java">  <SCRIPT type="text/javascript" src="../..//java.js" /> <TABLE class="tabs"><TR> <TD id="tab_colour" class="active"><A HREF='javascript:set_style("colour")'>Coloured</A></TD> <TD id="tab_raw" class="inactive"><A HREF='javascript:set_style("raw")'>Raw</A></TD> </TR></TABLE> <DIV id="colour" class="display"> <PRE class="colour" id="code"> <SPAN id='line_0' class='line_number'> </SPAN> <SPAN id='line_1' class='line_number'> 1</SPAN><span class='comment'>// Copyright 2007, Tim Vernum</span> <SPAN id='line_2' class='line_number'> 2</SPAN><span class='comment'>// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation </span> <SPAN id='line_3' class='line_number'> 3</SPAN><span class='comment'>// files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy,</span> <SPAN id='line_4' class='line_number'> 4</SPAN><span class='comment'>// modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the</span> <SPAN id='line_5' class='line_number'> 5</SPAN><span class='comment'>// Software is furnished to do so, subject to the following conditions:</span> <SPAN id='line_6' class='line_number'> 6</SPAN><span class='comment'>// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.</span> <SPAN id='line_7' class='line_number'> 7</SPAN><span class='comment'>// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE </span> <SPAN id='line_8' class='line_number'> 8</SPAN><span class='comment'>// WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR </span> <SPAN id='line_9' class='line_number'> 9</SPAN><span class='comment'>// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,</span> <SPAN id='line_10' class='line_number'>10</SPAN><span class='comment'>// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.</span> <SPAN id='line_11' class='line_number'>11</SPAN> <SPAN id='line_12' class='line_number'>12</SPAN><span class='package'>package</span> security<span class='operator'>.</span>user<span class='operator'>;</span> <SPAN id='line_13' class='line_number'>13</SPAN> <SPAN id='line_14' class='line_number'>14</SPAN><span class='access'>public</span> <span class='typedef'>class</span> UserContext <SPAN id='line_15' class='line_number'>15</SPAN>{ <SPAN id='line_16' class='line_number'>16</SPAN> <span class='access'>private</span> <span class='storage'>static</span> <span class='storage'>final</span> ThreadLocal<span class='generic'><UserContext></span> CURRENT <span class='operator'>=</span> <span class='operator'>new</span> ThreadLocal<span class='generic'><UserContext></span>()<span class='operator'>;</span> <SPAN id='line_17' class='line_number'>17</SPAN> <SPAN id='line_18' class='line_number'>18</SPAN> <span class='access'>private</span> User <span class='member'>_user</span><span class='operator'>;</span> <SPAN id='line_19' class='line_number'>19</SPAN> <SPAN id='line_20' class='line_number'>20</SPAN> <span class='access'>public</span> <span class='storage'>static</span> UserContext begin(User user) <SPAN id='line_21' class='line_number'>21</SPAN> { <SPAN id='line_22' class='line_number'>22</SPAN> checkNotActive()<span class='operator'>;</span> <SPAN id='line_23' class='line_number'>23</SPAN> UserContext context <span class='operator'>=</span> <span class='operator'>new</span> UserContext(user)<span class='operator'>;</span> <SPAN id='line_24' class='line_number'>24</SPAN> CURRENT<span class='operator'>.</span>set(context)<span class='operator'>;</span> <SPAN id='line_25' class='line_number'>25</SPAN> <span class='flow'>return</span> context<span class='operator'>;</span> <SPAN id='line_26' class='line_number'>26</SPAN> } <SPAN id='line_27' class='line_number'>27</SPAN> <SPAN id='line_28' class='line_number'>28</SPAN> <span class='access'>private</span> <span class='storage'>static</span> <span class='type'>void</span> checkNotActive() <SPAN id='line_29' class='line_number'>29</SPAN> { <SPAN id='line_30' class='line_number'>30</SPAN> UserContext active <span class='operator'>=</span> CURRENT<span class='operator'>.</span>get()<span class='operator'>;</span> <SPAN id='line_31' class='line_number'>31</SPAN> <span class='loop'>if</span> (active !<span class='operator'>=</span> <span class='operator'>null</span>) <SPAN id='line_32' class='line_number'>32</SPAN> { <SPAN id='line_33' class='line_number'>33</SPAN> <span class='throw'>throw</span> <span class='operator'>new</span> <span class='type'>IllegalStateException</span>(<span class='string'>"There is already an active user context: "</span> <span class='operator'>+</span> active)<span class='operator'>;</span> <SPAN id='line_34' class='line_number'>34</SPAN> } <SPAN id='line_35' class='line_number'>35</SPAN> } <SPAN id='line_36' class='line_number'>36</SPAN> <SPAN id='line_37' class='line_number'>37</SPAN> <span class='access'>public</span> <span class='storage'>static</span> UserContext get() <SPAN id='line_38' class='line_number'>38</SPAN> { <SPAN id='line_39' class='line_number'>39</SPAN> UserContext active <span class='operator'>=</span> CURRENT<span class='operator'>.</span>get()<span class='operator'>;</span> <SPAN id='line_40' class='line_number'>40</SPAN> <span class='loop'>if</span> (active <span class='operator'>=</span><span class='operator'>=</span> <span class='operator'>null</span>) <SPAN id='line_41' class='line_number'>41</SPAN> { <SPAN id='line_42' class='line_number'>42</SPAN> <span class='throw'>throw</span> <span class='operator'>new</span> <span class='type'>IllegalStateException</span>(<span class='string'>"There is no active user context"</span>)<span class='operator'>;</span> <SPAN id='line_43' class='line_number'>43</SPAN> } <SPAN id='line_44' class='line_number'>44</SPAN> <span class='flow'>return</span> active<span class='operator'>;</span> <SPAN id='line_45' class='line_number'>45</SPAN> } <SPAN id='line_46' class='line_number'>46</SPAN> <SPAN id='line_47' class='line_number'>47</SPAN> <span class='access'>private</span> UserContext(User user) <SPAN id='line_48' class='line_number'>48</SPAN> { <SPAN id='line_49' class='line_number'>49</SPAN> <span class='member'>_user</span> <span class='operator'>=</span> user<span class='operator'>;</span> <SPAN id='line_50' class='line_number'>50</SPAN> } <SPAN id='line_51' class='line_number'>51</SPAN> <SPAN id='line_52' class='line_number'>52</SPAN> <span class='access'>public</span> <span class='type'>void</span> end() <SPAN id='line_53' class='line_number'>53</SPAN> { <SPAN id='line_54' class='line_number'>54</SPAN> CURRENT<span class='operator'>.</span>set(<span class='operator'>null</span>)<span class='operator'>;</span> <SPAN id='line_55' class='line_number'>55</SPAN> <span class='member'>_user</span> <span class='operator'>=</span> <span class='operator'>null</span><span class='operator'>;</span> <SPAN id='line_56' class='line_number'>56</SPAN> } <SPAN id='line_57' class='line_number'>57</SPAN> <SPAN id='line_58' class='line_number'>58</SPAN> <span class='access'>public</span> <span class='type'>String</span> toString() <SPAN id='line_59' class='line_number'>59</SPAN> { <SPAN id='line_60' class='line_number'>60</SPAN> <span class='flow'>return</span> getClass()<span class='operator'>.</span>getSimpleName() <span class='operator'>+</span> <span class='string'>":"</span> <span class='operator'>+</span> <span class='member'>_user</span><span class='operator'>.</span>toString()<span class='operator'>;</span> <SPAN id='line_61' class='line_number'>61</SPAN> } <SPAN id='line_62' class='line_number'>62</SPAN> <SPAN id='line_63' class='line_number'>63</SPAN> <span class='access'>public</span> User getUser() <SPAN id='line_64' class='line_number'>64</SPAN> { <SPAN id='line_65' class='line_number'>65</SPAN> <span class='flow'>return</span> <span class='member'>_user</span><span class='operator'>;</span> <SPAN id='line_66' class='line_number'>66</SPAN> } <SPAN id='line_67' class='line_number'>67</SPAN>} <SPAN id='line_last' class='line_number'> </SPAN> </PRE></DIV> <DIV id='raw' class='hidden'><PRE class='raw'>// Copyright 2007, Tim Vernum // Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation // files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, // modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the // Software is furnished to do so, subject to the following conditions: // The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE // WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR // COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. package security.user; public class UserContext { private static final ThreadLocal<UserContext> CURRENT = new ThreadLocal<UserContext>(); private User _user; public static UserContext begin(User user) { checkNotActive(); UserContext context = new UserContext(user); CURRENT.set(context); return context; } private static void checkNotActive() { UserContext active = CURRENT.get(); if (active != null) { throw new IllegalStateException("There is already an active user context: " + active); } } public static UserContext get() { UserContext active = CURRENT.get(); if (active == null) { throw new IllegalStateException("There is no active user context"); } return active; } private UserContext(User user) { _user = user; } public void end() { CURRENT.set(null); _user = null; } public String toString() { return getClass().getSimpleName() + ":" + _user.toString(); } public User getUser() { return