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<pre><span class="sourceLineNo">001</span>// ***************************************************************************************************************************<a name="line.1"></a>
<span class="sourceLineNo">002</span>// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file *<a name="line.2"></a>
<span class="sourceLineNo">003</span>// * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file *<a name="line.3"></a>
<span class="sourceLineNo">004</span>// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance *<a name="line.4"></a>
<span class="sourceLineNo">005</span>// * with the License. You may obtain a copy of the License at *<a name="line.5"></a>
<span class="sourceLineNo">006</span>// * *<a name="line.6"></a>
<span class="sourceLineNo">007</span>// * http://www.apache.org/licenses/LICENSE-2.0 *<a name="line.7"></a>
<span class="sourceLineNo">008</span>// * *<a name="line.8"></a>
<span class="sourceLineNo">009</span>// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an *<a name="line.9"></a>
<span class="sourceLineNo">010</span>// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the *<a name="line.10"></a>
<span class="sourceLineNo">011</span>// * specific language governing permissions and limitations under the License. *<a name="line.11"></a>
<span class="sourceLineNo">012</span>// ***************************************************************************************************************************<a name="line.12"></a>
<span class="sourceLineNo">013</span>package org.apache.juneau;<a name="line.13"></a>
<span class="sourceLineNo">014</span><a name="line.14"></a>
<span class="sourceLineNo">015</span>import java.lang.reflect.*;<a name="line.15"></a>
<span class="sourceLineNo">016</span>import java.util.*;<a name="line.16"></a>
<span class="sourceLineNo">017</span>import java.util.function.*;<a name="line.17"></a>
<span class="sourceLineNo">018</span><a name="line.18"></a>
<span class="sourceLineNo">019</span>import org.apache.juneau.reflect.*;<a name="line.19"></a>
<span class="sourceLineNo">020</span><a name="line.20"></a>
<span class="sourceLineNo">021</span>/**<a name="line.21"></a>
<span class="sourceLineNo">022</span> * Represents a simple settable value.<a name="line.22"></a>
<span class="sourceLineNo">023</span> *<a name="line.23"></a>
<span class="sourceLineNo">024</span> * &lt;p&gt;<a name="line.24"></a>
<span class="sourceLineNo">025</span> * Similar to an {@link Optional} but mutable.<a name="line.25"></a>
<span class="sourceLineNo">026</span> *<a name="line.26"></a>
<span class="sourceLineNo">027</span> * &lt;ul class='notes'&gt;<a name="line.27"></a>
<span class="sourceLineNo">028</span> * &lt;li class='warn'&gt;This class is not thread safe.<a name="line.28"></a>
<span class="sourceLineNo">029</span> * &lt;/ul&gt;<a name="line.29"></a>
<span class="sourceLineNo">030</span> *<a name="line.30"></a>
<span class="sourceLineNo">031</span> * &lt;ul class='seealso'&gt;<a name="line.31"></a>
<span class="sourceLineNo">032</span> * &lt;li class='extlink'&gt;{@source}<a name="line.32"></a>
<span class="sourceLineNo">033</span> * &lt;/ul&gt;<a name="line.33"></a>
<span class="sourceLineNo">034</span> *<a name="line.34"></a>
<span class="sourceLineNo">035</span> * @param &lt;T&gt; The value type.<a name="line.35"></a>
<span class="sourceLineNo">036</span> */<a name="line.36"></a>
<span class="sourceLineNo">037</span>public class Value&lt;T&gt; {<a name="line.37"></a>
<span class="sourceLineNo">038</span><a name="line.38"></a>
<span class="sourceLineNo">039</span> //-----------------------------------------------------------------------------------------------------------------<a name="line.39"></a>
<span class="sourceLineNo">040</span> // Static<a name="line.40"></a>
<span class="sourceLineNo">041</span> //-----------------------------------------------------------------------------------------------------------------<a name="line.41"></a>
<span class="sourceLineNo">042</span><a name="line.42"></a>
<span class="sourceLineNo">043</span> /**<a name="line.43"></a>
<span class="sourceLineNo">044</span> * Static creator.<a name="line.44"></a>
<span class="sourceLineNo">045</span> *<a name="line.45"></a>
<span class="sourceLineNo">046</span> * @param &lt;T&gt; The value type.<a name="line.46"></a>
<span class="sourceLineNo">047</span> * @param object The object being wrapped.<a name="line.47"></a>
<span class="sourceLineNo">048</span> * @return A new {@link Value} object.<a name="line.48"></a>
<span class="sourceLineNo">049</span> */<a name="line.49"></a>
<span class="sourceLineNo">050</span> public static &lt;T&gt; Value&lt;T&gt; of(T object) {<a name="line.50"></a>
<span class="sourceLineNo">051</span> return new Value&lt;&gt;(object);<a name="line.51"></a>
<span class="sourceLineNo">052</span> }<a name="line.52"></a>
<span class="sourceLineNo">053</span><a name="line.53"></a>
<span class="sourceLineNo">054</span> /**<a name="line.54"></a>
<span class="sourceLineNo">055</span> * Static creator.<a name="line.55"></a>
<span class="sourceLineNo">056</span> *<a name="line.56"></a>
<span class="sourceLineNo">057</span> * @param &lt;T&gt; The value type.<a name="line.57"></a>
<span class="sourceLineNo">058</span> * @return An empty {@link Value} object.<a name="line.58"></a>
<span class="sourceLineNo">059</span> */<a name="line.59"></a>
<span class="sourceLineNo">060</span> public static &lt;T&gt; Value&lt;T&gt; empty() {<a name="line.60"></a>
<span class="sourceLineNo">061</span> return new Value&lt;&gt;(null);<a name="line.61"></a>
<span class="sourceLineNo">062</span> }<a name="line.62"></a>
<span class="sourceLineNo">063</span><a name="line.63"></a>
<span class="sourceLineNo">064</span> /**<a name="line.64"></a>
<span class="sourceLineNo">065</span> * Returns the generic parameter type of the Value type.<a name="line.65"></a>
<span class="sourceLineNo">066</span> *<a name="line.66"></a>
<span class="sourceLineNo">067</span> * @param t The type to find the parameter type of.<a name="line.67"></a>
<span class="sourceLineNo">068</span> * @return The parameter type of the value, or &lt;jk&gt;null&lt;/jk&gt; if the type is not a subclass of &lt;c&gt;Value&lt;/c&gt;.<a name="line.68"></a>
<span class="sourceLineNo">069</span> */<a name="line.69"></a>
<span class="sourceLineNo">070</span> public static Type getParameterType(Type t) {<a name="line.70"></a>
<span class="sourceLineNo">071</span> if (t instanceof ParameterizedType) {<a name="line.71"></a>
<span class="sourceLineNo">072</span> ParameterizedType pt = (ParameterizedType)t;<a name="line.72"></a>
<span class="sourceLineNo">073</span> if (pt.getRawType() == Value.class) {<a name="line.73"></a>
<span class="sourceLineNo">074</span> Type[] ta = pt.getActualTypeArguments();<a name="line.74"></a>
<span class="sourceLineNo">075</span> if (ta.length &gt; 0)<a name="line.75"></a>
<span class="sourceLineNo">076</span> return ta[0];<a name="line.76"></a>
<span class="sourceLineNo">077</span> }<a name="line.77"></a>
<span class="sourceLineNo">078</span> } else if (t instanceof Class) {<a name="line.78"></a>
<span class="sourceLineNo">079</span> Class&lt;?&gt; c = (Class&lt;?&gt;)t;<a name="line.79"></a>
<span class="sourceLineNo">080</span> if (Value.class.isAssignableFrom(c)) {<a name="line.80"></a>
<span class="sourceLineNo">081</span> return ClassInfo.of(c).getParameterType(0, Value.class);<a name="line.81"></a>
<span class="sourceLineNo">082</span> }<a name="line.82"></a>
<span class="sourceLineNo">083</span> }<a name="line.83"></a>
<span class="sourceLineNo">084</span><a name="line.84"></a>
<span class="sourceLineNo">085</span> return null;<a name="line.85"></a>
<span class="sourceLineNo">086</span> }<a name="line.86"></a>
<span class="sourceLineNo">087</span><a name="line.87"></a>
<span class="sourceLineNo">088</span> /**<a name="line.88"></a>
<span class="sourceLineNo">089</span> * Returns the unwrapped type.<a name="line.89"></a>
<span class="sourceLineNo">090</span> *<a name="line.90"></a>
<span class="sourceLineNo">091</span> * @param t The type to unwrap.<a name="line.91"></a>
<span class="sourceLineNo">092</span> * @return The unwrapped type, or the same type if the type isn't {@link Value}.<a name="line.92"></a>
<span class="sourceLineNo">093</span> */<a name="line.93"></a>
<span class="sourceLineNo">094</span> public static Type unwrap(Type t) {<a name="line.94"></a>
<span class="sourceLineNo">095</span> Type x = getParameterType(t);<a name="line.95"></a>
<span class="sourceLineNo">096</span> return x != null ? x : t;<a name="line.96"></a>
<span class="sourceLineNo">097</span> }<a name="line.97"></a>
<span class="sourceLineNo">098</span><a name="line.98"></a>
<span class="sourceLineNo">099</span> /**<a name="line.99"></a>
<span class="sourceLineNo">100</span> * Convenience method for checking if the specified type is this class.<a name="line.100"></a>
<span class="sourceLineNo">101</span> *<a name="line.101"></a>
<span class="sourceLineNo">102</span> * @param t The type to check.<a name="line.102"></a>
<span class="sourceLineNo">103</span> * @return &lt;jk&gt;true&lt;/jk&gt; if the specified type is this class.<a name="line.103"></a>
<span class="sourceLineNo">104</span> */<a name="line.104"></a>
<span class="sourceLineNo">105</span> public static boolean isType(Type t) {<a name="line.105"></a>
<span class="sourceLineNo">106</span> return<a name="line.106"></a>
<span class="sourceLineNo">107</span> (t instanceof ParameterizedType &amp;&amp; ((ParameterizedType)t).getRawType() == Value.class)<a name="line.107"></a>
<span class="sourceLineNo">108</span> || (t instanceof Class &amp;&amp; Value.class.isAssignableFrom((Class&lt;?&gt;)t));<a name="line.108"></a>
<span class="sourceLineNo">109</span> }<a name="line.109"></a>
<span class="sourceLineNo">110</span><a name="line.110"></a>
<span class="sourceLineNo">111</span> //-----------------------------------------------------------------------------------------------------------------<a name="line.111"></a>
<span class="sourceLineNo">112</span> // Implementation<a name="line.112"></a>
<span class="sourceLineNo">113</span> //-----------------------------------------------------------------------------------------------------------------<a name="line.113"></a>
<span class="sourceLineNo">114</span><a name="line.114"></a>
<span class="sourceLineNo">115</span><a name="line.115"></a>
<span class="sourceLineNo">116</span> private T t;<a name="line.116"></a>
<span class="sourceLineNo">117</span> private ValueListener&lt;T&gt; listener;<a name="line.117"></a>
<span class="sourceLineNo">118</span><a name="line.118"></a>
<span class="sourceLineNo">119</span> /**<a name="line.119"></a>
<span class="sourceLineNo">120</span> * Constructor.<a name="line.120"></a>
<span class="sourceLineNo">121</span> */<a name="line.121"></a>
<span class="sourceLineNo">122</span> public Value() {}<a name="line.122"></a>
<span class="sourceLineNo">123</span><a name="line.123"></a>
<span class="sourceLineNo">124</span> /**<a name="line.124"></a>
<span class="sourceLineNo">125</span> * Constructor.<a name="line.125"></a>
<span class="sourceLineNo">126</span> *<a name="line.126"></a>
<span class="sourceLineNo">127</span> * @param t Initial value.<a name="line.127"></a>
<span class="sourceLineNo">128</span> */<a name="line.128"></a>
<span class="sourceLineNo">129</span> public Value(T t) {<a name="line.129"></a>
<span class="sourceLineNo">130</span> set(t);<a name="line.130"></a>
<span class="sourceLineNo">131</span> }<a name="line.131"></a>
<span class="sourceLineNo">132</span><a name="line.132"></a>
<span class="sourceLineNo">133</span> /**<a name="line.133"></a>
<span class="sourceLineNo">134</span> * Adds a listener for this value.<a name="line.134"></a>
<span class="sourceLineNo">135</span> *<a name="line.135"></a>
<span class="sourceLineNo">136</span> * @param listener The new listener for this value.<a name="line.136"></a>
<span class="sourceLineNo">137</span> * @return This object.<a name="line.137"></a>
<span class="sourceLineNo">138</span> */<a name="line.138"></a>
<span class="sourceLineNo">139</span> public Value&lt;T&gt; listener(ValueListener&lt;T&gt; listener) {<a name="line.139"></a>
<span class="sourceLineNo">140</span> this.listener = listener;<a name="line.140"></a>
<span class="sourceLineNo">141</span> return this;<a name="line.141"></a>
<span class="sourceLineNo">142</span> }<a name="line.142"></a>
<span class="sourceLineNo">143</span><a name="line.143"></a>
<span class="sourceLineNo">144</span> /**<a name="line.144"></a>
<span class="sourceLineNo">145</span> * Sets the value.<a name="line.145"></a>
<span class="sourceLineNo">146</span> *<a name="line.146"></a>
<span class="sourceLineNo">147</span> * @param t The new value.<a name="line.147"></a>
<span class="sourceLineNo">148</span> * @return This object.<a name="line.148"></a>
<span class="sourceLineNo">149</span> */<a name="line.149"></a>
<span class="sourceLineNo">150</span> public Value&lt;T&gt; set(T t) {<a name="line.150"></a>
<span class="sourceLineNo">151</span> this.t = t;<a name="line.151"></a>
<span class="sourceLineNo">152</span> if (listener != null)<a name="line.152"></a>
<span class="sourceLineNo">153</span> listener.onSet(t);<a name="line.153"></a>
<span class="sourceLineNo">154</span> return this;<a name="line.154"></a>
<span class="sourceLineNo">155</span> }<a name="line.155"></a>
<span class="sourceLineNo">156</span><a name="line.156"></a>
<span class="sourceLineNo">157</span> /**<a name="line.157"></a>
<span class="sourceLineNo">158</span> * Sets the value if it's not already set.<a name="line.158"></a>
<span class="sourceLineNo">159</span> *<a name="line.159"></a>
<span class="sourceLineNo">160</span> * @param t The new value.<a name="line.160"></a>
<span class="sourceLineNo">161</span> * @return This object.<a name="line.161"></a>
<span class="sourceLineNo">162</span> */<a name="line.162"></a>
<span class="sourceLineNo">163</span> public Value&lt;T&gt; setIfEmpty(T t) {<a name="line.163"></a>
<span class="sourceLineNo">164</span> if (isEmpty())<a name="line.164"></a>
<span class="sourceLineNo">165</span> set(t);<a name="line.165"></a>
<span class="sourceLineNo">166</span> return this;<a name="line.166"></a>
<span class="sourceLineNo">167</span> }<a name="line.167"></a>
<span class="sourceLineNo">168</span><a name="line.168"></a>
<span class="sourceLineNo">169</span> /**<a name="line.169"></a>
<span class="sourceLineNo">170</span> * Returns the value.<a name="line.170"></a>
<span class="sourceLineNo">171</span> *<a name="line.171"></a>
<span class="sourceLineNo">172</span> * @return The value, or &lt;jk&gt;null&lt;/jk&gt; if it is not set.<a name="line.172"></a>
<span class="sourceLineNo">173</span> */<a name="line.173"></a>
<span class="sourceLineNo">174</span> public T get() {<a name="line.174"></a>
<span class="sourceLineNo">175</span> return t;<a name="line.175"></a>
<span class="sourceLineNo">176</span> }<a name="line.176"></a>
<span class="sourceLineNo">177</span><a name="line.177"></a>
<span class="sourceLineNo">178</span> /**<a name="line.178"></a>
<span class="sourceLineNo">179</span> * Returns the value and then unsets it.<a name="line.179"></a>
<span class="sourceLineNo">180</span> *<a name="line.180"></a>
<span class="sourceLineNo">181</span> * @return The value before it was unset.<a name="line.181"></a>
<span class="sourceLineNo">182</span> */<a name="line.182"></a>
<span class="sourceLineNo">183</span> public T getAndUnset() {<a name="line.183"></a>
<span class="sourceLineNo">184</span> T t2 = t;<a name="line.184"></a>
<span class="sourceLineNo">185</span> t = null;<a name="line.185"></a>
<span class="sourceLineNo">186</span> return t2;<a name="line.186"></a>
<span class="sourceLineNo">187</span> }<a name="line.187"></a>
<span class="sourceLineNo">188</span><a name="line.188"></a>
<span class="sourceLineNo">189</span> /**<a name="line.189"></a>
<span class="sourceLineNo">190</span> * Returns &lt;jk&gt;true&lt;/jk&gt; if the value is set.<a name="line.190"></a>
<span class="sourceLineNo">191</span> *<a name="line.191"></a>
<span class="sourceLineNo">192</span> * @return &lt;jk&gt;true&lt;/jk&gt; if the value is set.<a name="line.192"></a>
<span class="sourceLineNo">193</span> */<a name="line.193"></a>
<span class="sourceLineNo">194</span> public boolean isPresent() {<a name="line.194"></a>
<span class="sourceLineNo">195</span> return get() != null;<a name="line.195"></a>
<span class="sourceLineNo">196</span> }<a name="line.196"></a>
<span class="sourceLineNo">197</span><a name="line.197"></a>
<span class="sourceLineNo">198</span> /**<a name="line.198"></a>
<span class="sourceLineNo">199</span> * If a value is present, invoke the specified consumer with the value, otherwise do nothing.<a name="line.199"></a>
<span class="sourceLineNo">200</span> *<a name="line.200"></a>
<span class="sourceLineNo">201</span> * @param consumer Block to be executed if a value is present.<a name="line.201"></a>
<span class="sourceLineNo">202</span> */<a name="line.202"></a>
<span class="sourceLineNo">203</span> public void ifPresent(Consumer&lt;? super T&gt; consumer) {<a name="line.203"></a>
<span class="sourceLineNo">204</span> if (t != null)<a name="line.204"></a>
<span class="sourceLineNo">205</span> consumer.accept(t);<a name="line.205"></a>
<span class="sourceLineNo">206</span> }<a name="line.206"></a>
<span class="sourceLineNo">207</span><a name="line.207"></a>
<span class="sourceLineNo">208</span> /**<a name="line.208"></a>
<span class="sourceLineNo">209</span> * Applies a mapping function against the contents of this value.<a name="line.209"></a>
<span class="sourceLineNo">210</span> *<a name="line.210"></a>
<span class="sourceLineNo">211</span> * @param &lt;T2&gt; The mapped value type.<a name="line.211"></a>
<span class="sourceLineNo">212</span> * @param mapper The mapping function.<a name="line.212"></a>
<span class="sourceLineNo">213</span> * @return The mapped value.<a name="line.213"></a>
<span class="sourceLineNo">214</span> */<a name="line.214"></a>
<span class="sourceLineNo">215</span> public &lt;T2&gt; Value&lt;T2&gt; map(Function&lt;? super T, T2&gt; mapper) {<a name="line.215"></a>
<span class="sourceLineNo">216</span> if (t != null)<a name="line.216"></a>
<span class="sourceLineNo">217</span> return Value.of(mapper.apply(t));<a name="line.217"></a>
<span class="sourceLineNo">218</span> return Value.empty();<a name="line.218"></a>
<span class="sourceLineNo">219</span> }<a name="line.219"></a>
<span class="sourceLineNo">220</span><a name="line.220"></a>
<span class="sourceLineNo">221</span> /**<a name="line.221"></a>
<span class="sourceLineNo">222</span> * Returns the contents of this value or the default value if &lt;jk&gt;null&lt;/jk&gt;.<a name="line.222"></a>
<span class="sourceLineNo">223</span> *<a name="line.223"></a>
<span class="sourceLineNo">224</span> * @param def The default value.<a name="line.224"></a>
<span class="sourceLineNo">225</span> * @return The contents of this value or the default value if &lt;jk&gt;null&lt;/jk&gt;.<a name="line.225"></a>
<span class="sourceLineNo">226</span> */<a name="line.226"></a>
<span class="sourceLineNo">227</span> public T orElse(T def) {<a name="line.227"></a>
<span class="sourceLineNo">228</span> return t == null ? def : t;<a name="line.228"></a>
<span class="sourceLineNo">229</span> }<a name="line.229"></a>
<span class="sourceLineNo">230</span> /**<a name="line.230"></a>
<span class="sourceLineNo">231</span> * Returns &lt;jk&gt;true&lt;/jk&gt; if the value is empty.<a name="line.231"></a>
<span class="sourceLineNo">232</span> *<a name="line.232"></a>
<span class="sourceLineNo">233</span> * @return &lt;jk&gt;true&lt;/jk&gt; if the value is empty.<a name="line.233"></a>
<span class="sourceLineNo">234</span> */<a name="line.234"></a>
<span class="sourceLineNo">235</span> public boolean isEmpty() {<a name="line.235"></a>
<span class="sourceLineNo">236</span> return t == null;<a name="line.236"></a>
<span class="sourceLineNo">237</span> }<a name="line.237"></a>
<span class="sourceLineNo">238</span><a name="line.238"></a>
<span class="sourceLineNo">239</span> /**<a name="line.239"></a>
<span class="sourceLineNo">240</span> * Return the value if present, otherwise invoke {@code other} and return<a name="line.240"></a>
<span class="sourceLineNo">241</span> * the result of that invocation.<a name="line.241"></a>
<span class="sourceLineNo">242</span> *<a name="line.242"></a>
<span class="sourceLineNo">243</span> * @param other a {@code Supplier} whose result is returned if no value<a name="line.243"></a>
<span class="sourceLineNo">244</span> * is present<a name="line.244"></a>
<span class="sourceLineNo">245</span> * @return the value if present otherwise the result of {@code other.get()}<a name="line.245"></a>
<span class="sourceLineNo">246</span> * @throws NullPointerException if value is not present and {@code other} is<a name="line.246"></a>
<span class="sourceLineNo">247</span> * null<a name="line.247"></a>
<span class="sourceLineNo">248</span> */<a name="line.248"></a>
<span class="sourceLineNo">249</span> public T orElseGet(Supplier&lt;? extends T&gt; other) {<a name="line.249"></a>
<span class="sourceLineNo">250</span> return t != null ? t : other.get();<a name="line.250"></a>
<span class="sourceLineNo">251</span> }<a name="line.251"></a>
<span class="sourceLineNo">252</span><a name="line.252"></a>
<span class="sourceLineNo">253</span> /**<a name="line.253"></a>
<span class="sourceLineNo">254</span> * Return the contained value, if present, otherwise throw an exception<a name="line.254"></a>
<span class="sourceLineNo">255</span> * to be created by the provided supplier.<a name="line.255"></a>
<span class="sourceLineNo">256</span> *<a name="line.256"></a>
<span class="sourceLineNo">257</span> * @param &lt;X&gt; The exception type.<a name="line.257"></a>
<span class="sourceLineNo">258</span> * @param exceptionSupplier The supplier which will return the exception to<a name="line.258"></a>
<span class="sourceLineNo">259</span> * be thrown<a name="line.259"></a>
<span class="sourceLineNo">260</span> * @return the present value<a name="line.260"></a>
<span class="sourceLineNo">261</span> * @throws X if there is no value present<a name="line.261"></a>
<span class="sourceLineNo">262</span> * @throws NullPointerException if no value is present and<a name="line.262"></a>
<span class="sourceLineNo">263</span> * {@code exceptionSupplier} is null<a name="line.263"></a>
<span class="sourceLineNo">264</span> */<a name="line.264"></a>
<span class="sourceLineNo">265</span> public &lt;X extends Throwable&gt; T orElseThrow(Supplier&lt;? extends X&gt; exceptionSupplier) throws X {<a name="line.265"></a>
<span class="sourceLineNo">266</span> if (t != null)<a name="line.266"></a>
<span class="sourceLineNo">267</span> return t;<a name="line.267"></a>
<span class="sourceLineNo">268</span> throw exceptionSupplier.get();<a name="line.268"></a>
<span class="sourceLineNo">269</span> }<a name="line.269"></a>
<span class="sourceLineNo">270</span><a name="line.270"></a>
<span class="sourceLineNo">271</span> @Override /* Object */<a name="line.271"></a>
<span class="sourceLineNo">272</span> public String toString() {<a name="line.272"></a>
<span class="sourceLineNo">273</span> return "Value("+t+")";<a name="line.273"></a>
<span class="sourceLineNo">274</span> }<a name="line.274"></a>
<span class="sourceLineNo">275</span>}<a name="line.275"></a>
</pre>
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