recordingoutputstream.html

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<a name="152" href="#152">152</a> 
<a name="153" href="#153">153</a>     <em>/**<em>*</em></em>
<a name="154" href="#154">154</a> <em>     * Create a new RecordingOutputStream.</em>
<a name="155" href="#155">155</a> <em>     *</em>
<a name="156" href="#156">156</a> <em>     * @param bufferSize Buffer size to use.</em>
<a name="157" href="#157">157</a> <em>     * @param backingFilename Name of backing file to use.</em>
<a name="158" href="#158">158</a> <em>     */</em>
<a name="159" href="#159">159</a>     <strong>public</strong> <a href="../../../org/archive/io/RecordingOutputStream.html">RecordingOutputStream</a>(<strong>int</strong> bufferSize, String backingFilename) {
<a name="160" href="#160">160</a>         <strong>this</strong>.buffer = <strong>new</strong> byte[bufferSize];
<a name="161" href="#161">161</a>         <strong>this</strong>.backingFilename = backingFilename;
<a name="162" href="#162">162</a>         recording = <strong>true</strong>;
<a name="163" href="#163">163</a>     }
<a name="164" href="#164">164</a> 
<a name="165" href="#165">165</a>     <em>/**<em>*</em></em>
<a name="166" href="#166">166</a> <em>     * Wrap the given stream, both recording and passing along any data written</em>
<a name="167" href="#167">167</a> <em>     * to this RecordingOutputStream.</em>
<a name="168" href="#168">168</a> <em>     *</em>
<a name="169" href="#169">169</a> <em>     * @throws IOException If failed creation of backing file.</em>
<a name="170" href="#170">170</a> <em>     */</em>
<a name="171" href="#171">171</a>     <strong>public</strong> <strong>void</strong> open() throws IOException {
<a name="172" href="#172">172</a>         <strong>this</strong>.open(<strong>null</strong>);
<a name="173" href="#173">173</a>     }
<a name="174" href="#174">174</a> 
<a name="175" href="#175">175</a>     <em>/**<em>*</em></em>
<a name="176" href="#176">176</a> <em>     * Wrap the given stream, both recording and passing along any data written</em>
<a name="177" href="#177">177</a> <em>     * to this RecordingOutputStream.</em>
<a name="178" href="#178">178</a> <em>     *</em>
<a name="179" href="#179">179</a> <em>     * @param wrappedStream Stream to wrap.  May be null for case where we</em>
<a name="180" href="#180">180</a> <em>     * want to write to a file backed stream only.</em>
<a name="181" href="#181">181</a> <em>     *</em>
<a name="182" href="#182">182</a> <em>     * @throws IOException If failed creation of backing file.</em>
<a name="183" href="#183">183</a> <em>     */</em>
<a name="184" href="#184">184</a>     <strong>public</strong> <strong>void</strong> open(OutputStream wrappedStream) throws IOException {
<a name="185" href="#185">185</a>         <strong>if</strong>(isOpen()) {
<a name="186" href="#186">186</a>             <em class="comment">// error; should not be opening/wrapping in an unclosed </em>
<a name="187" href="#187">187</a>             <em class="comment">// stream remains open</em>
<a name="188" href="#188">188</a>             <strong>throw</strong> <strong>new</strong> IOException(<span class="string">"ROS already open for "</span>
<a name="189" href="#189">189</a>                     +Thread.currentThread().getName());
<a name="190" href="#190">190</a>         }
<a name="191" href="#191">191</a>         <strong>this</strong>.out = wrappedStream;
<a name="192" href="#192">192</a>         <strong>this</strong>.position = 0;
<a name="193" href="#193">193</a>         <strong>this</strong>.markPosition = 0;
<a name="194" href="#194">194</a>         <strong>this</strong>.maxPosition = 0; 
<a name="195" href="#195">195</a>         <strong>this</strong>.size = 0;
<a name="196" href="#196">196</a>         <strong>this</strong>.contentBeginMark = -1;
<a name="197" href="#197">197</a>         <em class="comment">// ensure recording turned on</em>
<a name="198" href="#198">198</a>         <strong>this</strong>.recording = <strong>true</strong>;
<a name="199" href="#199">199</a>         <em class="comment">// Always begins false; must use startDigest() to begin</em>
<a name="200" href="#200">200</a>         <strong>this</strong>.shouldDigest = false;
<a name="201" href="#201">201</a>         <strong>if</strong> (<strong>this</strong>.diskStream != <strong>null</strong>) {
<a name="202" href="#202">202</a>             closeDiskStream();
<a name="203" href="#203">203</a>         }
<a name="204" href="#204">204</a>         <strong>if</strong> (<strong>this</strong>.diskStream == <strong>null</strong>) {
<a name="205" href="#205">205</a>             <em class="comment">// TODO: Fix so we only make file when its actually needed.</em>
<a name="206" href="#206">206</a>             FileOutputStream fis = <strong>new</strong> FileOutputStream(<strong>this</strong>.backingFilename);
<a name="207" href="#207">207</a>             
<a name="208" href="#208">208</a>             <strong>this</strong>.diskStream = <strong>new</strong> <a href="../../../org/archive/io/RecyclingFastBufferedOutputStream.html">RecyclingFastBufferedOutputStream</a>(fis, bufStreamBuf);
<a name="209" href="#209">209</a>         }
<a name="210" href="#210">210</a>         startTime = System.currentTimeMillis();
<a name="211" href="#211">211</a>     }
<a name="212" href="#212">212</a> 
<a name="213" href="#213">213</a>     <strong>public</strong> <strong>void</strong> write(<strong>int</strong> b) throws IOException {
<a name="214" href="#214">214</a>         <strong>if</strong>(position&lt;maxPosition) {
<a name="215" href="#215">215</a>             <em class="comment">// revisiting previous content; do nothing but advance position</em>
<a name="216" href="#216">216</a>             position++;
<a name="217" href="#217">217</a>             <strong>return</strong>; 
<a name="218" href="#218">218</a>         }
<a name="219" href="#219">219</a>         <strong>if</strong>(recording) {
<a name="220" href="#220">220</a>             record(b);
<a name="221" href="#221">221</a>         }
<a name="222" href="#222">222</a>         <strong>if</strong> (<strong>this</strong>.out != <strong>null</strong>) {
<a name="223" href="#223">223</a>             <strong>this</strong>.out.write(b);
<a name="224" href="#224">224</a>         }
<a name="225" href="#225">225</a>         checkLimits();
<a name="226" href="#226">226</a>     }
<a name="227" href="#227">227</a> 
<a name="228" href="#228">228</a>     <strong>public</strong> <strong>void</strong> write(byte[] b, <strong>int</strong> off, <strong>int</strong> len) throws IOException {
<a name="229" href="#229">229</a>         <strong>if</strong>(position &lt; maxPosition) {
<a name="230" href="#230">230</a>             <strong>if</strong>(position+len&lt;=maxPosition) {
<a name="231" href="#231">231</a>                 <em class="comment">// revisiting; do nothing but advance position</em>
<a name="232" href="#232">232</a>                 position += len;
<a name="233" href="#233">233</a>                 <strong>return</strong>;
<a name="234" href="#234">234</a>             }
<a name="235" href="#235">235</a>             <em class="comment">// consume part of the array doing nothing but advancing position</em>
<a name="236" href="#236">236</a>             <strong>long</strong> consumeRange = maxPosition - position; 
<a name="237" href="#237">237</a>             position += consumeRange;
<a name="238" href="#238">238</a>             off += consumeRange;
<a name="239" href="#239">239</a>             len -= consumeRange; 
<a name="240" href="#240">240</a>         }
<a name="241" href="#241">241</a>         <strong>if</strong>(recording) {
<a name="242" href="#242">242</a>             record(b, off, len);
<a name="243" href="#243">243</a>         }
<a name="244" href="#244">244</a>         <strong>if</strong> (<strong>this</strong>.out != <strong>null</strong>) {
<a name="245" href="#245">245</a>             <strong>this</strong>.out.write(b, off, len);
<a name="246" href="#246">246</a>         }
<a name="247" href="#247">247</a>         checkLimits();
<a name="248" href="#248">248</a>     }
<a name="249" href="#249">249</a>     
<a name="250" href="#250">250</a>     <em>/**<em>*</em></em>
<a name="251" href="#251">251</a> <em>     * Check any enforced limits. </em>
<a name="252" href="#252">252</a> <em>     */</em>
<a name="253" href="#253">253</a>     <strong>protected</strong> <strong>void</strong> checkLimits() throws RecorderIOException {
<a name="254" href="#254">254</a>         <em class="comment">// too much material before finding end of headers? </em>
<a name="255" href="#255">255</a>         <strong>if</strong> (contentBeginMark&lt;0) {
<a name="256" href="#256">256</a>             <em class="comment">// no mark yet</em>
<a name="257" href="#257">257</a>             <strong>if</strong>(position>MAX_HEADER_MATERIAL) {
<a name="258" href="#258">258</a>                 <strong>throw</strong> <strong>new</strong> <a href="../../../org/archive/io/RecorderTooMuchHeaderException.html">RecorderTooMuchHeaderException</a>();
<a name="259" href="#259">259</a>             }
<a name="260" href="#260">260</a>         }
<a name="261" href="#261">261</a>         <em class="comment">// overlong?</em>
<a name="262" href="#262">262</a>         <strong>if</strong>(position>maxLength) {
<a name="263" href="#263">263</a>             <strong>throw</strong> <strong>new</strong> <a href="../../../org/archive/io/RecorderLengthExceededException.html">RecorderLengthExceededException</a>(); 
<a name="264" href="#264">264</a>         }
<a name="265" href="#265">265</a>         <em class="comment">// taking too long? </em>
<a name="266" href="#266">266</a>         <strong>long</strong> duration = System.currentTimeMillis() - startTime + 1; <em class="comment">// !divzero</em>
<a name="267" href="#267">267</a>         <strong>if</strong>(duration>timeoutMs) {
<a name="268" href="#268">268</a>             <strong>throw</strong> <strong>new</strong> <a href="../../../org/archive/io/RecorderTimeoutException.html">RecorderTimeoutException</a>(); 
<a name="269" href="#269">269</a>         }
<a name="270" href="#270">270</a>         <em class="comment">// need to throttle reading to hit max configured rate? </em>
<a name="271" href="#271">271</a>         <strong>if</strong>(position/duration > maxRateBytesPerMs) {
<a name="272" href="#272">272</a>             <strong>long</strong> desiredDuration = position / maxRateBytesPerMs;
<a name="273" href="#273">273</a>             <strong>try</strong> {
<a name="274" href="#274">274</a>                 Thread.sleep(desiredDuration-duration);
<a name="275" href="#275">275</a>             } <strong>catch</strong> (InterruptedException e) {
<a name="276" href="#276">276</a>                 logger.log(Level.WARNING,
<a name="277" href="#277">277</a>                         <span class="string">"bandwidth throttling sleep interrupted"</span>, e);
<a name="278" href="#278">278</a>             } 
<a name="279" href="#279">279</a>         }
<a name="280" href="#280">280</a>     }
<a name="281" href="#281">281</a> 
<a name="282" href="#282">282</a>     <em>/**<em>*</em></em>
<a name="283" href="#283">283</a> <em>     * Record the given byte for later recovery</em>
<a name="284" href="#284">284</a> <em>     *</em>
<a name="285" href="#285">285</a> <em>     * @param b Int to record.</em>
<a name="286" href="#286">286</a> <em>     *</em>
<a name="287" href="#287">287</a> <em>     * @exception IOException Failed write to backing file.</em>
<a name="288" href="#288">288</a> <em>     */</em>
<a name="289" href="#289">289</a>     <strong>private</strong> <strong>void</strong> record(<strong>int</strong> b) throws IOException {
<a name="290" href="#290">290</a>         <strong>if</strong> (<strong>this</strong>.shouldDigest) {
<a name="291" href="#291">291</a>             <strong>this</strong>.digest.update((byte)b);
<a name="292" href="#292">292</a>         }
<a name="293" href="#293">293</a>         <strong>if</strong> (<strong>this</strong>.position >= <strong>this</strong>.buffer.length) {
<a name="294" href="#294">294</a>             <em class="comment">// TODO: Its possible to call write w/o having first opened a</em>
<a name="295" href="#295">295</a>             <em class="comment">// stream.  Protect ourselves against this.</em>
<a name="296" href="#296">296</a>             assert <strong>this</strong>.diskStream != <strong>null</strong>: <span class="string">"Diskstream is null"</span>;
<a name="297" href="#297">297</a>             <strong>this</strong>.diskStream.write(b);
<a name="298" href="#298">298</a>         } <strong>else</strong> {
<a name="299" href="#299">299</a>             <strong>this</strong>.buffer[(<strong>int</strong>) <strong>this</strong>.position] = (byte) b;
<a name="300" href="#300">300</a>         }
<a name="301" href="#301">301</a>         <strong>this</strong>.position++;
<a name="302" href="#302">302</a>     }
<a name="303" href="#303">303</a> 
<a name="304" href="#304">304</a>     <em>/**<em>*</em></em>
<a name="305" href="#305">305</a> <em>     * Record the given byte-array range for recovery later</em>
<a name="306" href="#306">306</a> <em>     *</em>
<a name="307" href="#307">307</a> <em>     * @param b Buffer to record.</em>
<a name="308" href="#308">308</a> <em>     * @param off Offset into buffer at which to start recording.</em>
<a name="309" href="#309">309</a> <em>     * @param len Length of buffer to record.</em>
<a name="310" href="#310">310</a> <em>     *</em>
<a name="311" href="#311">311</a> <em>     * @exception IOException Failed write to backing file.</em>