statemachine.html

MINA+API 关于MINA的API

<a name="94" href="#94">94</a>  <em class="jxr_javadoccomment">     * @param id the id of the {@link State} to return.</em>
<a name="95" href="#95">95</a>  <em class="jxr_javadoccomment">     * @return the {@link State}</em>
<a name="96" href="#96">96</a>  <em class="jxr_javadoccomment">     * @throws NoSuchStateException if no matching {@link State} could be found.</em>
<a name="97" href="#97">97</a>  <em class="jxr_javadoccomment">     */</em>
<a name="98" href="#98">98</a>      <strong class="jxr_keyword">public</strong> <a href="../../../../org/apache/mina/statemachine/State.html">State</a> getState(String id) <strong class="jxr_keyword">throws</strong> NoSuchStateException {
<a name="99" href="#99">99</a>          <a href="../../../../org/apache/mina/statemachine/State.html">State</a> state = states.get(id);
<a name="100" href="#100">100</a>         <strong class="jxr_keyword">if</strong> (state == <strong class="jxr_keyword">null</strong>) {
<a name="101" href="#101">101</a>             <strong class="jxr_keyword">throw</strong> <strong class="jxr_keyword">new</strong> <a href="../../../../org/apache/mina/statemachine/NoSuchStateException.html">NoSuchStateException</a>(id);
<a name="102" href="#102">102</a>         }
<a name="103" href="#103">103</a>         <strong class="jxr_keyword">return</strong> state;
<a name="104" href="#104">104</a>     }
<a name="105" href="#105">105</a> 
<a name="106" href="#106">106</a>     <em class="jxr_javadoccomment">/**</em>
<a name="107" href="#107">107</a> <em class="jxr_javadoccomment">     * Returns an unmodifiable {@link Collection} of all {@link State}s used by</em>
<a name="108" href="#108">108</a> <em class="jxr_javadoccomment">     * this {@link StateMachine}.</em>
<a name="109" href="#109">109</a> <em class="jxr_javadoccomment">     * </em>
<a name="110" href="#110">110</a> <em class="jxr_javadoccomment">     * @return the {@link State}s.</em>
<a name="111" href="#111">111</a> <em class="jxr_javadoccomment">     */</em>
<a name="112" href="#112">112</a>     <strong class="jxr_keyword">public</strong> Collection&lt;State&gt; getStates() {
<a name="113" href="#113">113</a>         <strong class="jxr_keyword">return</strong> Collections.unmodifiableCollection(states.values());
<a name="114" href="#114">114</a>     }
<a name="115" href="#115">115</a>     
<a name="116" href="#116">116</a>     <em class="jxr_javadoccomment">/**</em>
<a name="117" href="#117">117</a> <em class="jxr_javadoccomment">     * Processes the specified {@link Event} through this {@link StateMachine}.</em>
<a name="118" href="#118">118</a> <em class="jxr_javadoccomment">     * Normally you wouldn't call this directly but rather use</em>
<a name="119" href="#119">119</a> <em class="jxr_javadoccomment">     * {@link StateMachineProxyFactory} to create a proxy for an interface of</em>
<a name="120" href="#120">120</a> <em class="jxr_javadoccomment">     * your choice. Any method calls on the proxy will be translated into</em>
<a name="121" href="#121">121</a> <em class="jxr_javadoccomment">     * {@link Event} objects and then fed to the {@link StateMachine} by the</em>
<a name="122" href="#122">122</a> <em class="jxr_javadoccomment">     * proxy using this method.</em>
<a name="123" href="#123">123</a> <em class="jxr_javadoccomment">     * </em>
<a name="124" href="#124">124</a> <em class="jxr_javadoccomment">     * @param event the {@link Event} to be handled.</em>
<a name="125" href="#125">125</a> <em class="jxr_javadoccomment">     */</em>
<a name="126" href="#126">126</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> handle(<a href="../../../../org/apache/mina/statemachine/event/Event.html">Event</a> event) {
<a name="127" href="#127">127</a>         <a href="../../../../org/apache/mina/statemachine/context/StateContext.html">StateContext</a> context = event.getContext();
<a name="128" href="#128">128</a> 
<a name="129" href="#129">129</a>         <strong class="jxr_keyword">synchronized</strong> (context) {
<a name="130" href="#130">130</a>             LinkedList&lt;Event&gt; eventQueue = eventQueueThreadLocal.get();
<a name="131" href="#131">131</a>             eventQueue.addLast(event);
<a name="132" href="#132">132</a> 
<a name="133" href="#133">133</a>             <strong class="jxr_keyword">if</strong> (processingThreadLocal.get()) {
<a name="134" href="#134">134</a>                 <em class="jxr_comment">/*</em>
<a name="135" href="#135">135</a> <em class="jxr_comment">                 * This thread is already processing an event. Queue this </em>
<a name="136" href="#136">136</a> <em class="jxr_comment">                 * event.</em>
<a name="137" href="#137">137</a> <em class="jxr_comment">                 */</em>
<a name="138" href="#138">138</a>                 <strong class="jxr_keyword">if</strong> (log.isDebugEnabled()) {
<a name="139" href="#139">139</a>                     log.debug(<span class="jxr_string">"State machine called recursively. Queuing event "</span> + event
<a name="140" href="#140">140</a>                             + <span class="jxr_string">" for later processing."</span>);
<a name="141" href="#141">141</a>                 }
<a name="142" href="#142">142</a>             } <strong class="jxr_keyword">else</strong> {
<a name="143" href="#143">143</a>                 processingThreadLocal.set(<strong class="jxr_keyword">true</strong>);
<a name="144" href="#144">144</a>                 <strong class="jxr_keyword">try</strong> {
<a name="145" href="#145">145</a>                     <strong class="jxr_keyword">if</strong> (context.getCurrentState() == <strong class="jxr_keyword">null</strong>) {
<a name="146" href="#146">146</a>                         context.setCurrentState(startState);
<a name="147" href="#147">147</a>                     }
<a name="148" href="#148">148</a>                     processEvents(eventQueue);
<a name="149" href="#149">149</a>                 } <strong class="jxr_keyword">finally</strong> {
<a name="150" href="#150">150</a>                     processingThreadLocal.set(false);
<a name="151" href="#151">151</a>                 }
<a name="152" href="#152">152</a>             }
<a name="153" href="#153">153</a>         }
<a name="154" href="#154">154</a> 
<a name="155" href="#155">155</a>     }
<a name="156" href="#156">156</a> 
<a name="157" href="#157">157</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> processEvents(LinkedList&lt;Event&gt; eventQueue) {
<a name="158" href="#158">158</a>         <strong class="jxr_keyword">while</strong> (!eventQueue.isEmpty()) {
<a name="159" href="#159">159</a>             <a href="../../../../org/apache/mina/statemachine/event/Event.html">Event</a> event = eventQueue.removeFirst();
<a name="160" href="#160">160</a>             <a href="../../../../org/apache/mina/statemachine/context/StateContext.html">StateContext</a> context = event.getContext();
<a name="161" href="#161">161</a>             handle(context.getCurrentState(), event);
<a name="162" href="#162">162</a>         }
<a name="163" href="#163">163</a>     }
<a name="164" href="#164">164</a>     
<a name="165" href="#165">165</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> handle(<a href="../../../../org/apache/mina/statemachine/State.html">State</a> state, <a href="../../../../org/apache/mina/statemachine/event/Event.html">Event</a> event) {
<a name="166" href="#166">166</a>         <a href="../../../../org/apache/mina/statemachine/context/StateContext.html">StateContext</a> context = event.getContext();
<a name="167" href="#167">167</a> 
<a name="168" href="#168">168</a>         <strong class="jxr_keyword">for</strong> (Transition t : state.getTransitions()) {
<a name="169" href="#169">169</a>             <strong class="jxr_keyword">if</strong> (log.isDebugEnabled()) {
<a name="170" href="#170">170</a>                 log.debug(<span class="jxr_string">"Trying transition "</span> + t);
<a name="171" href="#171">171</a>             }
<a name="172" href="#172">172</a> 
<a name="173" href="#173">173</a>             <strong class="jxr_keyword">try</strong> {
<a name="174" href="#174">174</a>                 <strong class="jxr_keyword">if</strong> (t.execute(event)) {
<a name="175" href="#175">175</a>                     <strong class="jxr_keyword">if</strong> (log.isDebugEnabled()) {
<a name="176" href="#176">176</a>                         log.debug(<span class="jxr_string">"Transition "</span> + t + <span class="jxr_string">" executed successfully."</span>);
<a name="177" href="#177">177</a>                     }
<a name="178" href="#178">178</a>                     setCurrentState(context, t.getNextState());
<a name="179" href="#179">179</a> 
<a name="180" href="#180">180</a>                     <strong class="jxr_keyword">return</strong>;
<a name="181" href="#181">181</a>                 }
<a name="182" href="#182">182</a>             } <strong class="jxr_keyword">catch</strong> (BreakAndContinueException bace) {
<a name="183" href="#183">183</a>                 <strong class="jxr_keyword">if</strong> (log.isDebugEnabled()) {
<a name="184" href="#184">184</a>                     log.debug(<span class="jxr_string">"BreakAndContinueException thrown in "</span> 
<a name="185" href="#185">185</a>                             + <span class="jxr_string">"transition "</span> + t
<a name="186" href="#186">186</a>                             + <span class="jxr_string">". Continuing with next transition."</span>);
<a name="187" href="#187">187</a>                 }
<a name="188" href="#188">188</a>             } <strong class="jxr_keyword">catch</strong> (BreakAndGotoException bage) {
<a name="189" href="#189">189</a>                 <a href="../../../../org/apache/mina/statemachine/State.html">State</a> newState = getState(bage.getStateId());
<a name="190" href="#190">190</a> 
<a name="191" href="#191">191</a>                 <strong class="jxr_keyword">if</strong> (bage.isNow()) {
<a name="192" href="#192">192</a>                     <strong class="jxr_keyword">if</strong> (log.isDebugEnabled()) {
<a name="193" href="#193">193</a>                         log.debug(<span class="jxr_string">"BreakAndGotoException thrown in "</span> 
<a name="194" href="#194">194</a>                                 + <span class="jxr_string">"transition "</span> + t + <span class="jxr_string">". Moving to state "</span>
<a name="195" href="#195">195</a>                                 + newState.getId() + <span class="jxr_string">" now."</span>);
<a name="196" href="#196">196</a>                     }