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id="headerTableRow2"><td align="left"><span id="nsrTitle">IndexReader<span class="languageSpecificText"><span class="cs">.</span><span class="vb">.</span><span class="cpp">::</span><span class="nu">.</span><span class="fs">.</span></span>Reopen Method </span></td></tr><tr id="headerTableRow3"><td align="left"><a href="4919df1c-c434-d92d-ae43-1f44d0246cd4.htm">IndexReader Class</a> <a href="#seeAlsoToggle" onclick="OpenSection(seeAlsoToggle)">See Also</a> <span id="headfeedbackarea" class="feedbackhead"><a href="javascript:SubmitFeedback('','Lucene.Net Class 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class="heading"><span onclick="ExpandCollapse(overloadMembersTableToggle)" style="cursor:default;" onkeypress="ExpandCollapse_CheckKey(overloadMembersTableToggle, event)" tabindex="0"><img id="overloadMembersTableToggle" class="toggle" name="toggleSwitch" src="../icons/collapse_all.gif" />Overload List</span></h1><div id="overloadMembersTableSection" class="section" name="collapseableSection" style=""><table id="memberList" class="members" frame="lhs" cellpadding="2"><col width="10%" /><tr><th class="iconColumn"> | |
| </th><th class="nameColumn">Name</th><th class="descriptionColumn">Description</th></tr><tr data="public;declared;notNetfw;"><td><img src="../icons/pubmethod.gif" alt="Public method" title="Public method" /></td><td><a href="558b74b4-e8be-807a-5041-19342e99d995.htm">Reopen<span class="languageSpecificText"><span class="cs">()</span><span class="cpp">()</span><span class="nu">()</span><span class="fs">()</span></span></a></td><td><div class="summary"> Refreshes an IndexReader if the index has changed since this instance | |
| was (re)opened. | |
| <p /> | |
| Opening an IndexReader is an expensive operation. This method can be used | |
| to refresh an existing IndexReader to reduce these costs. This method | |
| tries to only load segments that have changed or were created after the | |
| IndexReader was (re)opened. | |
| <p /> | |
| If the index has not changed since this instance was (re)opened, then this | |
| call is a NOOP and returns this instance. Otherwise, a new instance is | |
| returned. The old instance is <b>not</b> closed and remains usable.<br /><p /> | |
| If the reader is reopened, even though they share | |
| resources internally, it's safe to make changes | |
| (deletions, norms) with the new reader. All shared | |
| mutable state obeys "copy on write" semantics to ensure | |
| the changes are not seen by other readers. | |
| <p /> | |
| You can determine whether a reader was actually reopened by comparing the | |
| old instance with the instance returned by this method: | |
| <pre> | |
| IndexReader reader = ... | |
| ... | |
| IndexReader newReader = r.reopen(); | |
| if (newReader != reader) { | |
| ... // reader was reopened | |
| reader.close(); | |
| } | |
| reader = newReader; | |
| ... | |
| </pre> | |
| Be sure to synchronize that code so that other threads, | |
| if present, can never use reader after it has been | |
| closed and before it's switched to newReader. | |
| <p /><b>NOTE</b>: If this reader is a near real-time | |
| reader (obtained from {@link IndexWriter#GetReader()}, | |
| reopen() will simply call writer.getReader() again for | |
| you, though this may change in the future. | |
| </div></td></tr><tr data="public;declared;notNetfw;"><td><img src="../icons/pubmethod.gif" alt="Public method" title="Public method" /></td><td><a href="4dde9004-25d5-46fb-eb87-e95346e1ed32.htm">Reopen(Boolean)</a></td><td><div class="summary">Just like {@link #Reopen()}, except you can change the | |
| readOnly of the original reader. If the index is | |
| unchanged but readOnly is different then a new reader | |
| will be returned. | |
| </div></td></tr><tr data="public;declared;notNetfw;"><td><img src="../icons/pubmethod.gif" alt="Public method" title="Public method" /></td><td><a href="0085d4a9-7640-0a39-763f-6f2b20d4e5aa.htm">Reopen(IndexCommit)</a></td><td><div class="summary">Expert: reopen this reader on a specific commit point. | |
| This always returns a readOnly reader. If the | |
| specified commit point matches what this reader is | |
| already on, and this reader is already readOnly, then | |
| this same instance is returned; if it is not already | |
| readOnly, a readOnly clone is returned. | |
| </div></td></tr></table></div><h1 class="heading"><span onclick="ExpandCollapse(seeAlsoToggle)" style="cursor:default;" onkeypress="ExpandCollapse_CheckKey(seeAlsoToggle, event)" tabindex="0"><img id="seeAlsoToggle" class="toggle" name="toggleSwitch" src="../icons/collapse_all.gif" />See Also</span></h1><div id="seeAlsoSection" class="section" name="collapseableSection" style=""><div class="seeAlsoStyle"><a href="4919df1c-c434-d92d-ae43-1f44d0246cd4.htm">IndexReader Class</a></div><div class="seeAlsoStyle"><a href="a75ca848-3f25-fa1a-cf57-b3399fdccad7.htm">IndexReader Members</a></div><div class="seeAlsoStyle"><a href="4d52bcdb-050f-b66e-6d74-d7169ebc88b0.htm">Lucene.Net.Index Namespace</a></div></div></div><div id="footer"><div class="footerLine"><img width="100%" height="3px" src="../icons/footer.gif" alt="Footer image" title="Footer image" /></div><A NAME="feedback"></A><span id="fb" class="feedbackcss"></span></div></div></body></html> |