bytereplaycharsequence.html

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<a name="244" href="#244">244</a>             }
<a name="245" href="#245">245</a>             <strong>return</strong> charAt(index - <strong>this</strong>.contentOffset);
<a name="246" href="#246">246</a>         }
<a name="247" href="#247">247</a>         <em class="comment">// Moving backward</em>
<a name="248" href="#248">248</a>         recenterBuffer(index);
<a name="249" href="#249">249</a>         <strong>return</strong> charAt(index - <strong>this</strong>.contentOffset);
<a name="250" href="#250">250</a>     }
<a name="251" href="#251">251</a> 
<a name="252" href="#252">252</a>     <em>/**<em>*</em></em>
<a name="253" href="#253">253</a> <em>     * Move the buffer window on backing file back centering current access</em>
<a name="254" href="#254">254</a> <em>     * position in middle of window.</em>
<a name="255" href="#255">255</a> <em>     *</em>
<a name="256" href="#256">256</a> <em>     * @param index Index of character to access.</em>
<a name="257" href="#257">257</a> <em>     */</em>
<a name="258" href="#258">258</a>     <strong>private</strong> <strong>void</strong> recenterBuffer(<strong>int</strong> index) {
<a name="259" href="#259">259</a>         <strong>if</strong> (logger.isLoggable(Level.FINE)) {
<a name="260" href="#260">260</a>             logger.fine(<span class="string">"Recentering around "</span> + index + <span class="string">" in "</span> +
<a name="261" href="#261">261</a>                 <strong>this</strong>.backingFilename);
<a name="262" href="#262">262</a>         }
<a name="263" href="#263">263</a>         <strong>this</strong>.wrapOrigin = index - (<strong>this</strong>.wraparoundBuffer.length / 2);
<a name="264" href="#264">264</a>         <strong>if</strong>(<strong>this</strong>.wrapOrigin &lt; <strong>this</strong>.prefixBuffer.length) {
<a name="265" href="#265">265</a>             <strong>this</strong>.wrapOrigin = <strong>this</strong>.prefixBuffer.length;
<a name="266" href="#266">266</a>         }
<a name="267" href="#267">267</a>         <strong>this</strong>.wrapOffset = 0;
<a name="268" href="#268">268</a>         loadBuffer();
<a name="269" href="#269">269</a>     }
<a name="270" href="#270">270</a> 
<a name="271" href="#271">271</a>     <em>/**<em>*</em></em>
<a name="272" href="#272">272</a> <em>     * Load from backing file into the wrapper buffer.</em>
<a name="273" href="#273">273</a> <em>     */</em>
<a name="274" href="#274">274</a>     <strong>private</strong> <strong>void</strong> loadBuffer()
<a name="275" href="#275">275</a>     {
<a name="276" href="#276">276</a>         <strong>long</strong> len = -1;
<a name="277" href="#277">277</a>         <strong>try</strong> {
<a name="278" href="#278">278</a>             len = <strong>this</strong>.raFile.length();
<a name="279" href="#279">279</a>             <strong>this</strong>.raFile.seek(<strong>this</strong>.wrapOrigin - <strong>this</strong>.prefixBuffer.length);
<a name="280" href="#280">280</a>             <strong>this</strong>.raFile.readFully(<strong>this</strong>.wraparoundBuffer, 0,
<a name="281" href="#281">281</a>                 Math.min(<strong>this</strong>.wraparoundBuffer.length,
<a name="282" href="#282">282</a>                      <strong>this</strong>.absoluteLength - <strong>this</strong>.wrapOrigin));
<a name="283" href="#283">283</a>         }
<a name="284" href="#284">284</a> 
<a name="285" href="#285">285</a>         <strong>catch</strong> (IOException e) {
<a name="286" href="#286">286</a>             <em class="comment">// TODO convert this to a runtime error?</em>
<a name="287" href="#287">287</a>             DevUtils.logger.log (
<a name="288" href="#288">288</a>                 Level.SEVERE,
<a name="289" href="#289">289</a>                 <span class="string">"raFile.seek("</span> +
<a name="290" href="#290">290</a>                 (<strong>this</strong>.wrapOrigin - <strong>this</strong>.prefixBuffer.length) +
<a name="291" href="#291">291</a>                 <span class="string">")\n"</span> +
<a name="292" href="#292">292</a>                 <span class="string">"raFile.readFully(wraparoundBuffer,0,"</span> +
<a name="293" href="#293">293</a>                 (Math.min(<strong>this</strong>.wraparoundBuffer.length,
<a name="294" href="#294">294</a>                     <strong>this</strong>.length - <strong>this</strong>.wrapOrigin )) +
<a name="295" href="#295">295</a>                 <span class="string">")\n"</span>+
<a name="296" href="#296">296</a>                 <span class="string">"raFile.length()"</span> + len + <span class="string">"\n"</span> +
<a name="297" href="#297">297</a>                 DevUtils.extraInfo(),
<a name="298" href="#298">298</a>                 e);
<a name="299" href="#299">299</a>             <strong>throw</strong> <strong>new</strong> RuntimeException(e);
<a name="300" href="#300">300</a>         }
<a name="301" href="#301">301</a>     }
<a name="302" href="#302">302</a> 
<a name="303" href="#303">303</a>     <em>/**<em>*</em></em>
<a name="304" href="#304">304</a> <em>     * Roll the wraparound buffer forward one position</em>
<a name="305" href="#305">305</a> <em>     */</em>
<a name="306" href="#306">306</a>     <strong>private</strong> <strong>void</strong> advanceBuffer() {
<a name="307" href="#307">307</a>         <strong>try</strong> {
<a name="308" href="#308">308</a>             <strong>this</strong>.wraparoundBuffer[<strong>this</strong>.wrapOffset] =
<a name="309" href="#309">309</a>                 (byte)<strong>this</strong>.raFile.read();
<a name="310" href="#310">310</a>             <strong>this</strong>.wrapOffset++;
<a name="311" href="#311">311</a>             <strong>this</strong>.wrapOffset %= <strong>this</strong>.wraparoundBuffer.length;
<a name="312" href="#312">312</a>             <strong>this</strong>.wrapOrigin++;
<a name="313" href="#313">313</a>         } <strong>catch</strong> (IOException e) {
<a name="314" href="#314">314</a>             DevUtils.logger.log(Level.SEVERE, <span class="string">"advanceBuffer()"</span> +
<a name="315" href="#315">315</a>                 DevUtils.extraInfo(), e);
<a name="316" href="#316">316</a>             <strong>throw</strong> <strong>new</strong> RuntimeException(e);
<a name="317" href="#317">317</a>         }
<a name="318" href="#318">318</a>     }
<a name="319" href="#319">319</a> 
<a name="320" href="#320">320</a>     <strong>public</strong> CharSequence subSequence(<strong>int</strong> start, <strong>int</strong> end) {
<a name="321" href="#321">321</a>         <strong>return</strong> <strong>new</strong> <a href="../../../org/archive/io/CharSubSequence.html">CharSubSequence</a>(<strong>this</strong>, start, end);
<a name="322" href="#322">322</a>     }
<a name="323" href="#323">323</a> 
<a name="324" href="#324">324</a>     <em>/**<em>*</em></em>
<a name="325" href="#325">325</a> <em>     * Cleanup resources.</em>
<a name="326" href="#326">326</a> <em>     *</em>
<a name="327" href="#327">327</a> <em>     * @exception IOException Failed close of random access file.</em>
<a name="328" href="#328">328</a> <em>     */</em>
<a name="329" href="#329">329</a>     <strong>public</strong> <strong>void</strong> close() throws IOException
<a name="330" href="#330">330</a>     {
<a name="331" href="#331">331</a>         <strong>this</strong>.prefixBuffer = <strong>null</strong>;
<a name="332" href="#332">332</a>         <strong>if</strong> (<strong>this</strong>.raFile != <strong>null</strong>) {
<a name="333" href="#333">333</a>             <strong>this</strong>.raFile.close();
<a name="334" href="#334">334</a>             <strong>this</strong>.raFile = <strong>null</strong>;
<a name="335" href="#335">335</a>         }
<a name="336" href="#336">336</a>     }
<a name="337" href="#337">337</a> 
<a name="338" href="#338">338</a>     <em class="comment">/*<em class="comment"> (non-Javadoc)</em></em>
<a name="339" href="#339">339</a> <em class="comment">     * @see java.lang.Object#finalize()</em>
<a name="340" href="#340">340</a> <em class="comment">     */</em>
<a name="341" href="#341">341</a>     <strong>protected</strong> <strong>void</strong> finalize() throws Throwable
<a name="342" href="#342">342</a>     {
<a name="343" href="#343">343</a>         <strong>super</strong>.finalize();
<a name="344" href="#344">344</a>         close();
<a name="345" href="#345">345</a>     }
<a name="346" href="#346">346</a>     
<a name="347" href="#347">347</a>     <em>/**<em>*</em></em>
<a name="348" href="#348">348</a> <em>     * Convenience method for getting a substring. </em>
<a name="349" href="#349">349</a> <em>     * @deprecated please use subSequence() and then toString() directly </em>
<a name="350" href="#350">350</a> <em>     */</em>
<a name="351" href="#351">351</a>     <strong>public</strong> String substring(<strong>int</strong> offset, <strong>int</strong> len) {
<a name="352" href="#352">352</a>         <strong>return</strong> subSequence(offset, offset+len).toString();
<a name="353" href="#353">353</a>     }
<a name="354" href="#354">354</a> 
<a name="355" href="#355">355</a>     <em class="comment">/*<em class="comment"> (non-Javadoc)</em></em>
<a name="356" href="#356">356</a> <em class="comment">     * @see java.lang.Object#toString()</em>
<a name="357" href="#357">357</a> <em class="comment">     */</em>
<a name="358" href="#358">358</a>     <strong>public</strong> String toString() {
<a name="359" href="#359">359</a>         StringBuilder sb = <strong>new</strong> StringBuilder(<strong>this</strong>.length());
<a name="360" href="#360">360</a>         sb.append(<strong>this</strong>);
<a name="361" href="#361">361</a>         <strong>return</strong> sb.toString();
<a name="362" href="#362">362</a>     }
<a name="363" href="#363">363</a> }
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