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| <h1 id="Lucene_Net_Store" data-uid="Lucene.Net.Store" class="text-break">Namespace Lucene.Net.Store |
| </h1> |
| <div class="markdown level0 summary"><!-- |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You under the Apache License, Version 2.0 |
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| Unless required by applicable law or agreed to in writing, software |
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| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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| limitations under the License. |
| --> |
| <p>Binary i/o API, used for all index data.</p> |
| </div> |
| <div class="markdown level0 conceptual"></div> |
| <div class="markdown level0 remarks"></div> |
| <h3 id="classes">Classes |
| </h3> |
| <h4><a class="xref" href="Lucene.Net.Store.BaseDirectory.html">BaseDirectory</a></h4> |
| <section><p>Base implementation for a concrete <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a>. |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.BufferedChecksumIndexInput.html">BufferedChecksumIndexInput</a></h4> |
| <section><p>Simple implementation of <a class="xref" href="Lucene.Net.Store.ChecksumIndexInput.html">ChecksumIndexInput</a> that wraps |
| another input and delegates calls.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.BufferedIndexInput.html">BufferedIndexInput</a></h4> |
| <section><p>Base implementation class for buffered <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a>. </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.BufferedIndexOutput.html">BufferedIndexOutput</a></h4> |
| <section><p>Base implementation class for buffered <a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a>. </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.ByteArrayDataInput.html">ByteArrayDataInput</a></h4> |
| <section><p>DataInput backed by a byte array. |
| <strong>WARNING:</strong> this class omits all low-level checks. |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.ByteArrayDataOutput.html">ByteArrayDataOutput</a></h4> |
| <section><p>DataOutput backed by a byte array. |
| <strong>WARNING:</strong> this class omits most low-level checks, |
| so be sure to test heavily with assertions enabled. |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.ByteBufferIndexInput.html">ByteBufferIndexInput</a></h4> |
| <section><p>Base <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a> implementation that uses an array |
| of <span class="xref">J2N.IO.ByteBuffer</span>s to represent a file. |
| <p> |
| Because Java's <span class="xref">J2N.IO.ByteBuffer</span> uses an <span class="xref">System.Int32</span> to address the |
| values, it's necessary to access a file greater |
| <span class="xref">System.Int32.MaxValue</span> in size using multiple byte buffers. |
| <p> |
| For efficiency, this class requires that the buffers |
| are a power-of-two (<code>chunkSizePower</code>).</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.ChecksumIndexInput.html">ChecksumIndexInput</a></h4> |
| <section><p>Extension of <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a>, computing checksum as it goes. |
| Callers can retrieve the checksum via <a class="xref" href="Lucene.Net.Store.ChecksumIndexInput.html#Lucene_Net_Store_ChecksumIndexInput_Checksum">Checksum</a>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.CompoundFileDirectory.html">CompoundFileDirectory</a></h4> |
| <section><p>Class for accessing a compound stream. |
| This class implements a directory, but is limited to only read operations. |
| Directory methods that would normally modify data throw an exception. |
| <p> |
| All files belonging to a segment have the same name with varying extensions. |
| The extensions correspond to the different file formats used by the <a class="xref" href="Lucene.Net.Codecs.Codec.html">Codec</a>. |
| When using the Compound File format these files are collapsed into a |
| single <code>.cfs</code> file (except for the <a class="xref" href="Lucene.Net.Codecs.LiveDocsFormat.html">LiveDocsFormat</a>, with a |
| corresponding <code>.cfe</code> file indexing its sub-files. |
| <p> |
| Files: |
| <ul><li><code>.cfs</code>: An optional "virtual" file consisting of all the other |
| index files for systems that frequently run out of file handles.</li><li><code>.cfe</code>: The "virtual" compound file's entry table holding all |
| entries in the corresponding .cfs file.</li></ul> |
| <p>Description:</p> |
| <ul><li>Compound (.cfs) --> Header, FileData <sup>FileCount</sup></li><li>Compound Entry Table (.cfe) --> Header, FileCount, <FileName, |
| DataOffset, DataLength> <sup>FileCount</sup>, Footer</li><li>Header --> <a class="xref" href="Lucene.Net.Codecs.CodecUtil.html#Lucene_Net_Codecs_CodecUtil_WriteHeader_Lucene_Net_Store_DataOutput_System_String_System_Int32_">WriteHeader(DataOutput, String, Int32)</a></li><li>FileCount --> <a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteVInt32_System_Int32_">WriteVInt32(Int32)</a></li><li>DataOffset,DataLength --> <a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteInt64_System_Int64_">WriteInt64(Int64)</a></li><li>FileName --> <a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteString_System_String_">WriteString(String)</a></li><li>FileData --> raw file data</li><li>Footer --> <a class="xref" href="Lucene.Net.Codecs.CodecUtil.html#Lucene_Net_Codecs_CodecUtil_WriteFooter_Lucene_Net_Store_IndexOutput_">WriteFooter(IndexOutput)</a></li></ul> |
| <p>Notes:</p> |
| <ul><li>FileCount indicates how many files are contained in this compound file. |
| The entry table that follows has that many entries.</li><li>Each directory entry contains a long pointer to the start of this file's data |
| section, the files length, and a <span class="xref">System.String</span> with that file's name.</li></ul> |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.CompoundFileDirectory.FileEntry.html">CompoundFileDirectory.FileEntry</a></h4> |
| <section><p>Offset/Length for a slice inside of a compound file </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.DataInput.html">DataInput</a></h4> |
| <section><p>Abstract base class for performing read operations of Lucene's low-level |
| data types.</p> |
| <p><p><a class="xref" href="Lucene.Net.Store.DataInput.html">DataInput</a> may only be used from one thread, because it is not |
| thread safe (it keeps internal state like file position). To allow |
| multithreaded use, every <a class="xref" href="Lucene.Net.Store.DataInput.html">DataInput</a> instance must be cloned before |
| used in another thread. Subclasses must therefore implement <a class="xref" href="Lucene.Net.Store.DataInput.html#Lucene_Net_Store_DataInput_Clone">Clone()</a>, |
| returning a new <a class="xref" href="Lucene.Net.Store.DataInput.html">DataInput</a> which operates on the same underlying |
| resource, but positioned independently.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.DataOutput.html">DataOutput</a></h4> |
| <section><p>Abstract base class for performing write operations of Lucene's low-level |
| data types.</p> |
| <p><p><a class="xref" href="Lucene.Net.Store.DataOutput.html">DataOutput</a> may only be used from one thread, because it is not |
| thread safe (it keeps internal state like file position).</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> is a flat list of files. Files may be written once, when they |
| are created. Once a file is created it may only be opened for read, or |
| deleted. Random access is permitted both when reading and writing. |
| <p> |
| .NET's i/o APIs not used directly, but rather all i/o is |
| through this API. This permits things such as: |
| <ul><li> implementation of RAM-based indices;</li><li> implementation indices stored in a database;</li><li> implementation of an index as a single file;</li></ul> |
| <p> |
| Directory locking is implemented by an instance of |
| <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a>, and can be changed for each <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> |
| instance using <a class="xref" href="Lucene.Net.Store.Directory.html#Lucene_Net_Store_Directory_SetLockFactory_Lucene_Net_Store_LockFactory_">SetLockFactory(LockFactory)</a>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.Directory.IndexInputSlicer.html">Directory.IndexInputSlicer</a></h4> |
| <section><p>Allows to create one or more sliced <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a> instances from a single |
| file handle. Some <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> implementations may be able to efficiently map slices of a file |
| into memory when only certain parts of a file are required. |
| <p> |
| <div class="lucene-block lucene-internal">This is a Lucene.NET INTERNAL API, use at your own risk</div><div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.FileSwitchDirectory.html">FileSwitchDirectory</a></h4> |
| <section><p>Expert: A <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> instance that switches files between |
| two other <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> instances.</p> |
| <p><p>Files with the specified extensions are placed in the |
| primary directory; others are placed in the secondary |
| directory. The provided <span class="xref">ISet{string}</span> must not change once passed |
| to this class, and must allow multiple threads to call |
| contains at once. |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.FilterDirectory.html">FilterDirectory</a></h4> |
| <section><p>Directory implementation that delegates calls to another directory. |
| This class can be used to add limitations on top of an existing |
| <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> implementation such as |
| rate limiting (<a class="xref" href="Lucene.Net.Store.RateLimitedDirectoryWrapper.html">RateLimitedDirectoryWrapper</a>) or to add additional |
| sanity checks for tests. However, if you plan to write your own |
| <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> implementation, you should consider extending directly |
| <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> or <a class="xref" href="Lucene.Net.Store.BaseDirectory.html">BaseDirectory</a> rather than try to reuse |
| functionality of existing <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a>s by extending this class. |
| <p> |
| <div class="lucene-block lucene-internal">This is a Lucene.NET INTERNAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.FlushInfo.html">FlushInfo</a></h4> |
| <section><p>A FlushInfo provides information required for a FLUSH context. |
| It is used as part of an <a class="xref" href="Lucene.Net.Store.IOContext.html">IOContext</a> in case of FLUSH context.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.FSDirectory.html">FSDirectory</a></h4> |
| <section><p>Base class for <a class="xref" href="Lucene.Net.Store.FSDirectory.html#Lucene_Net_Store_FSDirectory_Directory">Directory</a> implementations that store index |
| files in the file system. |
| <p> |
| There are currently three core |
| subclasses:</p> |
| <ul><li> <a class="xref" href="Lucene.Net.Store.SimpleFSDirectory.html">SimpleFSDirectory</a> is a straightforward |
| implementation using <span class="xref">System.IO.FileStream</span>. |
| However, it has poor concurrent performance |
| (multiple threads will bottleneck) as it |
| synchronizes when multiple threads read from the |
| same file.</li><li> <a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a> uses java.nio's |
| FileChannel's positional io when reading to avoid |
| synchronization when reading from the same file. |
| Unfortunately, due to a Windows-only <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6265734">Sun |
| JRE bug</a> this is a poor choice for Windows, but |
| on all other platforms this is the preferred |
| choice. Applications using <span class="xref">System.Threading.Thread.Interrupt</span> or |
| <span class="xref">System.Threading.Tasks.Task`1</span> should use |
| <a class="xref" href="Lucene.Net.Store.SimpleFSDirectory.html">SimpleFSDirectory</a> instead. See <a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a> java doc |
| for details.</li><li> <a class="xref" href="Lucene.Net.Store.MMapDirectory.html">MMapDirectory</a> uses memory-mapped IO when |
| reading. This is a good choice if you have plenty |
| of virtual memory relative to your index size, eg |
| if you are running on a 64 bit runtime, or you are |
| running on a 32 bit runtime but your index sizes are |
| small enough to fit into the virtual memory space. |
| <p> |
| Applications using <span class="xref">System.Threading.Thread.Interrupt</span> or |
| <span class="xref">System.Threading.Tasks.Task`1</span> should use |
| <a class="xref" href="Lucene.Net.Store.SimpleFSDirectory.html">SimpleFSDirectory</a> instead. See <a class="xref" href="Lucene.Net.Store.MMapDirectory.html">MMapDirectory</a> |
| doc for details.</li></ul> |
| |
| <p>Unfortunately, because of system peculiarities, there is |
| no single overall best implementation. Therefore, we've |
| added the <a class="xref" href="Lucene.Net.Store.FSDirectory.html#Lucene_Net_Store_FSDirectory_Open_System_String_">Open(String)</a> method (or one of its overloads), to allow Lucene to choose |
| the best <a class="xref" href="Lucene.Net.Store.FSDirectory.html">FSDirectory</a> implementation given your |
| environment, and the known limitations of each |
| implementation. For users who have no reason to prefer a |
| specific implementation, it's best to simply use |
| <a class="xref" href="Lucene.Net.Store.FSDirectory.html#Lucene_Net_Store_FSDirectory_Open_System_String_">Open(String)</a> (or one of its overloads). For all others, you should instantiate the |
| desired implementation directly.</p> |
| <p><p>The locking implementation is by default |
| <a class="xref" href="Lucene.Net.Store.NativeFSLockFactory.html">NativeFSLockFactory</a>, but can be changed by |
| passing in a custom <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> instance.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.FSDirectory.FSIndexOutput.html">FSDirectory.FSIndexOutput</a></h4> |
| <section><p>Writes output with <span class="xref">System.IO.FileStream.Write(System.Byte[],System.Int32,System.Int32)</span></p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.FSLockFactory.html">FSLockFactory</a></h4> |
| <section><p>Base class for file system based locking implementation.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a></h4> |
| <section><p>Abstract base class for input from a file in a <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a>. A |
| random-access input stream. Used for all Lucene index input operations.</p> |
| <p><p><a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a> may only be used from one thread, because it is not |
| thread safe (it keeps internal state like file position). To allow |
| multithreaded use, every <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a> instance must be cloned before |
| used in another thread. Subclasses must therefore implement <a class="xref" href="Lucene.Net.Store.IndexInput.html#Lucene_Net_Store_IndexInput_Clone">Clone()</a>, |
| returning a new <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a> which operates on the same underlying |
| resource, but positioned independently. Lucene never closes cloned |
| <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a>s, it will only do this on the original one. |
| The original instance must take care that cloned instances throw |
| <span class="xref">System.ObjectDisposedException</span> when the original one is closed.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a></h4> |
| <section><p>Abstract base class for output to a file in a <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a>. A random-access |
| output stream. Used for all Lucene index output operations.</p> |
| <p><p><a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a> may only be used from one thread, because it is not |
| thread safe (it keeps internal state like file position).</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.InputStreamDataInput.html">InputStreamDataInput</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.DataInput.html">DataInput</a> wrapping a plain <span class="xref">System.IO.Stream</span>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.IOContext.html">IOContext</a></h4> |
| <section><a class="xref" href="Lucene.Net.Store.IOContext.html">IOContext</a> holds additional details on the merge/search context. A <a class="xref" href="Lucene.Net.Store.IOContext.html">IOContext</a> |
| object can never be initialized as null as passed as a parameter to either |
| <a class="xref" href="Lucene.Net.Store.Directory.html#Lucene_Net_Store_Directory_OpenInput_System_String_Lucene_Net_Store_IOContext_">OpenInput(String, IOContext)</a> or |
| <a class="xref" href="Lucene.Net.Store.Directory.html#Lucene_Net_Store_Directory_CreateOutput_System_String_Lucene_Net_Store_IOContext_">CreateOutput(String, IOContext)</a> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.Lock.html">Lock</a></h4> |
| <section><p>An interprocess mutex lock. |
| <p>Typical use might look like:</p> |
| <pre><code> var result = Lock.With.NewAnonymous<string>( |
| @lock: directory.MakeLock("my.lock"), |
| lockWaitTimeout: Lock.LOCK_OBTAIN_WAIT_FOREVER, |
| doBody: () => |
| { |
| //... code to execute while locked ... |
| return "the result"; |
| }).Run();</code></pre> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.Lock.With-1.html">Lock.With<T></a></h4> |
| <section><p>Utility class for executing code with exclusive access. </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a></h4> |
| <section><p>Base class for Locking implementation. <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> uses |
| instances of this class to implement locking.</p> |
| |
| <p>Lucene uses <a class="xref" href="Lucene.Net.Store.NativeFSLockFactory.html">NativeFSLockFactory</a> by default for |
| <a class="xref" href="Lucene.Net.Store.FSDirectory.html">FSDirectory</a>-based index directories.</p> |
| |
| <p>Special care needs to be taken if you change the locking |
| implementation: First be certain that no writer is in fact |
| writing to the index otherwise you can easily corrupt |
| your index. Be sure to do the <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> change on all Lucene |
| instances and clean up all leftover lock files before starting |
| the new configuration for the first time. Different implementations |
| can not work together!</p> |
| |
| <p>If you suspect that some <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> implementation is |
| not working properly in your environment, you can easily |
| test it by using <a class="xref" href="Lucene.Net.Store.VerifyingLockFactory.html">VerifyingLockFactory</a>, |
| <a class="xref" href="Lucene.Net.Store.LockVerifyServer.html">LockVerifyServer</a> and <a class="xref" href="Lucene.Net.Store.LockStressTest.html">LockStressTest</a>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.LockObtainFailedException.html">LockObtainFailedException</a></h4> |
| <section><p>This exception is thrown when the <code>write.lock</code> |
| could not be acquired. This |
| happens when a writer tries to open an index |
| that another writer already has open. </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.LockReleaseFailedException.html">LockReleaseFailedException</a></h4> |
| <section><p>This exception is thrown when the <code>write.lock</code> |
| could not be released. </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.LockStressTest.html">LockStressTest</a></h4> |
| <section><p>Simple standalone tool that forever acquires & releases a |
| lock using a specific <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a>. Run without any args |
| to see usage.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.LockVerifyServer.html">LockVerifyServer</a></h4> |
| <section><p>Simple standalone server that must be running when you |
| use <a class="xref" href="Lucene.Net.Store.VerifyingLockFactory.html">VerifyingLockFactory</a>. This server simply |
| verifies at most one process holds the lock at a time. |
| Run without any args to see usage.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.MergeInfo.html">MergeInfo</a></h4> |
| <section><p>A MergeInfo provides information required for a MERGE context. |
| It is used as part of an <a class="xref" href="Lucene.Net.Store.IOContext.html">IOContext</a> in case of MERGE context.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.MMapDirectory.html">MMapDirectory</a></h4> |
| <section><p>File-based <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> implementation that uses |
| <span class="xref">System.IO.MemoryMappedFiles.MemoryMappedFile</span> for reading, and |
| <a class="xref" href="Lucene.Net.Store.FSDirectory.FSIndexOutput.html">FSDirectory.FSIndexOutput</a> for writing.</p> |
| <p><strong>NOTE</strong>: memory mapping uses up a portion of the |
| virtual memory address space in your process equal to the |
| size of the file being mapped. Before using this class, |
| be sure your have plenty of virtual address space, e.g. by |
| using a 64 bit runtime, or a 32 bit runtime with indexes that are |
| guaranteed to fit within the address space. |
| On 32 bit platforms also consult <a class="xref" href="Lucene.Net.Store.MMapDirectory.html#Lucene_Net_Store_MMapDirectory__ctor_System_IO_DirectoryInfo_Lucene_Net_Store_LockFactory_System_Int32_">MMapDirectory(DirectoryInfo, LockFactory, Int32)</a> |
| if you have problems with mmap failing because of fragmented |
| address space. If you get an <span class="xref">System.OutOfMemoryException</span>, it is recommended |
| to reduce the chunk size, until it works. |
| <p> |
| <strong>NOTE:</strong> Accessing this class either directly or |
| indirectly from a thread while it's interrupted can close the |
| underlying channel immediately if at the same time the thread is |
| blocked on IO. The channel will remain closed and subsequent access |
| to <a class="xref" href="Lucene.Net.Store.MMapDirectory.html">MMapDirectory</a> will throw a <span class="xref">System.ObjectDisposedException</span>. |
| </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.MMapDirectory.MMapIndexInput.html">MMapDirectory.MMapIndexInput</a></h4> |
| <section></section> |
| <h4><a class="xref" href="Lucene.Net.Store.NativeFSLockFactory.html">NativeFSLockFactory</a></h4> |
| <section><p>Implements <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> using native OS file |
| locks. For NFS based access to an index, it's |
| recommended that you try <a class="xref" href="Lucene.Net.Store.SimpleFSLockFactory.html">SimpleFSLockFactory</a> |
| first and work around the one limitation that a lock file |
| could be left when the runtime exits abnormally.</p> |
| |
| <p>The primary benefit of <a class="xref" href="Lucene.Net.Store.NativeFSLockFactory.html">NativeFSLockFactory</a> is |
| that locks (not the lock file itsself) will be properly |
| removed (by the OS) if the runtime has an abnormal exit.</p> |
| |
| <p>Note that, unlike <a class="xref" href="Lucene.Net.Store.SimpleFSLockFactory.html">SimpleFSLockFactory</a>, the existence of |
| leftover lock files in the filesystem is fine because the OS |
| will free the locks held against these files even though the |
| files still remain. Lucene will never actively remove the lock |
| files, so although you see them, the index may not be locked.</p> |
| |
| <p>Special care needs to be taken if you change the locking |
| implementation: First be certain that no writer is in fact |
| writing to the index otherwise you can easily corrupt |
| your index. Be sure to do the <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> change on all Lucene |
| instances and clean up all leftover lock files before starting |
| the new configuration for the first time. Different implementations |
| can not work together!</p> |
| |
| <p>If you suspect that this or any other <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> is |
| not working properly in your environment, you can easily |
| test it by using <a class="xref" href="Lucene.Net.Store.VerifyingLockFactory.html">VerifyingLockFactory</a>, |
| <a class="xref" href="Lucene.Net.Store.LockVerifyServer.html">LockVerifyServer</a> and <a class="xref" href="Lucene.Net.Store.LockStressTest.html">LockStressTest</a>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a></h4> |
| <section><p>An <a class="xref" href="Lucene.Net.Store.FSDirectory.html">FSDirectory</a> implementation that uses <span class="xref">System.IO.FileStream</span>'s |
| positional read, which allows multiple threads to read from the same file |
| without synchronizing. |
| <p> |
| This class only uses <span class="xref">System.IO.FileStream</span> when reading; writing is achieved with |
| <a class="xref" href="Lucene.Net.Store.FSDirectory.FSIndexOutput.html">FSDirectory.FSIndexOutput</a>. |
| <p> |
| <strong>NOTE</strong>: <a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a> is not recommended on Windows because of a bug in |
| how FileChannel.read is implemented in Sun's JRE. Inside of the |
| implementation the position is apparently synchronized. See <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6265734">here</a> |
| for details. |
| </p> |
| <p> |
| <font color="red"><strong>NOTE:</strong> Accessing this class either directly or |
| indirectly from a thread while it's interrupted can close the |
| underlying file descriptor immediately if at the same time the thread is |
| blocked on IO. The file descriptor will remain closed and subsequent access |
| to <a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a> will throw a <span class="xref">System.ObjectDisposedException</span>. If |
| your application uses either <span class="xref">System.Threading.Thread.Interrupt</span> or |
| <span class="xref">System.Threading.Tasks.Task</span> you should use <a class="xref" href="Lucene.Net.Store.SimpleFSDirectory.html">SimpleFSDirectory</a> in |
| favor of <a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a>.</font> |
| </p></p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.NIOFSDirectory.NIOFSIndexInput.html">NIOFSDirectory.NIOFSIndexInput</a></h4> |
| <section><p>Reads bytes with the <span class="xref">Lucene.Net.Support.IO.StreamExtensions.Read(System.IO.Stream,J2N.IO.ByteBuffer,System.Int64)</span> |
| extension method for <span class="xref">System.IO.Stream</span>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.NoLockFactory.html">NoLockFactory</a></h4> |
| <section><p>Use this <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> to disable locking entirely. |
| Only one instance of this lock is created. You should call |
| <a class="xref" href="Lucene.Net.Store.NoLockFactory.html#Lucene_Net_Store_NoLockFactory_GetNoLockFactory">GetNoLockFactory()</a> to get the instance.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.NRTCachingDirectory.html">NRTCachingDirectory</a></h4> |
| <section><p>Wraps a <a class="xref" href="Lucene.Net.Store.RAMDirectory.html">RAMDirectory</a> |
| around any provided delegate directory, to |
| be used during NRT search.</p> |
| <p>This class is likely only useful in a near-real-time |
| context, where indexing rate is lowish but reopen |
| rate is highish, resulting in many tiny files being |
| written. This directory keeps such segments (as well as |
| the segments produced by merging them, as long as they |
| are small enough), in RAM.</p> |
| |
| <p>This is safe to use: when your app calls <a class="xref" href="Lucene.Net.Index.IndexWriter.html#Lucene_Net_Index_IndexWriter_Commit">Commit()</a>, |
| all cached files will be flushed from the cached and sync'd.</p> |
| |
| <p><p>Here's a simple example usage:</p> |
| <pre><code> Directory fsDir = FSDirectory.Open(new DirectoryInfo("/path/to/index")); |
| NRTCachingDirectory cachedFSDir = new NRTCachingDirectory(fsDir, 5.0, 60.0); |
| IndexWriterConfig conf = new IndexWriterConfig(Version.LUCENE_48, analyzer); |
| IndexWriter writer = new IndexWriter(cachedFSDir, conf);</code></pre> |
| |
| <p><p>This will cache all newly flushed segments, all merges |
| whose expected segment size is <= 5 MB, unless the net |
| cached bytes exceeds 60 MB at which point all writes will |
| not be cached (until the net bytes falls below 60 MB).</p> |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.OutputStreamDataOutput.html">OutputStreamDataOutput</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.DataOutput.html">DataOutput</a> wrapping a plain <span class="xref">System.IO.Stream</span>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.RAMDirectory.html">RAMDirectory</a></h4> |
| <section><p>A memory-resident <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> implementation. Locking |
| implementation is by default the <a class="xref" href="Lucene.Net.Store.SingleInstanceLockFactory.html">SingleInstanceLockFactory</a> |
| but can be changed with <a class="xref" href="Lucene.Net.Store.Directory.html#Lucene_Net_Store_Directory_SetLockFactory_Lucene_Net_Store_LockFactory_">SetLockFactory(LockFactory)</a>.</p> |
| <p><p><strong>Warning:</strong> This class is not intended to work with huge |
| indexes. Everything beyond several hundred megabytes will waste |
| resources (GC cycles), because it uses an internal buffer size |
| of 1024 bytes, producing millions of <span class="xref">byte[1024]</span> arrays. |
| This class is optimized for small memory-resident indexes. |
| It also has bad concurrency on multithreaded environments.</p> |
| <p><p>It is recommended to materialize large indexes on disk and use |
| <a class="xref" href="Lucene.Net.Store.MMapDirectory.html">MMapDirectory</a>, which is a high-performance directory |
| implementation working directly on the file system cache of the |
| operating system, so copying data to heap space is not useful.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.RAMFile.html">RAMFile</a></h4> |
| <section><p>Represents a file in RAM as a list of <span class="xref">byte[]</span> buffers. |
| <p> |
| <div class="lucene-block lucene-internal">This is a Lucene.NET INTERNAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.RAMInputStream.html">RAMInputStream</a></h4> |
| <section><p>A memory-resident <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a> implementation. |
| <p> |
| <div class="lucene-block lucene-internal">This is a Lucene.NET INTERNAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.RAMOutputStream.html">RAMOutputStream</a></h4> |
| <section><p>A memory-resident <a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a> implementation. |
| <p> |
| <div class="lucene-block lucene-internal">This is a Lucene.NET INTERNAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.RateLimitedDirectoryWrapper.html">RateLimitedDirectoryWrapper</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> wrapper that allows <a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a> rate limiting using |
| IO context (<a class="xref" href="Lucene.Net.Store.IOContext.UsageContext.html">IOContext.UsageContext</a>) specific rate limiters (<a class="xref" href="Lucene.Net.Store.RateLimiter.html">RateLimiter</a>). |
| <p> |
| <div class="lucene-block lucene-experimental">This is a Lucene.NET EXPERIMENTAL API, use at your own risk</div></section> |
| <h4><a class="xref" href="Lucene.Net.Store.RateLimiter.html">RateLimiter</a></h4> |
| <section><p>Abstract base class to rate limit IO. Typically implementations are |
| shared across multiple <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a>s or <a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a>s (for example |
| those involved all merging). Those <a class="xref" href="Lucene.Net.Store.IndexInput.html">IndexInput</a>s and |
| <a class="xref" href="Lucene.Net.Store.IndexOutput.html">IndexOutput</a>s would call <a class="xref" href="Lucene.Net.Store.RateLimiter.html#Lucene_Net_Store_RateLimiter_Pause_System_Int64_">Pause(Int64)</a> whenever they |
| want to read bytes or write bytes.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.RateLimiter.SimpleRateLimiter.html">RateLimiter.SimpleRateLimiter</a></h4> |
| <section><p>Simple class to rate limit IO.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.SimpleFSDirectory.html">SimpleFSDirectory</a></h4> |
| <section><p>A straightforward implementation of <a class="xref" href="Lucene.Net.Store.FSDirectory.html">FSDirectory</a> |
| using <span class="xref">System.IO.FileStream</span>. However, this class has |
| poor concurrent performance (multiple threads will |
| bottleneck) as it synchronizes when multiple threads |
| read from the same file. It's usually better to use |
| <a class="xref" href="Lucene.Net.Store.NIOFSDirectory.html">NIOFSDirectory</a> or <a class="xref" href="Lucene.Net.Store.MMapDirectory.html">MMapDirectory</a> instead.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.SimpleFSDirectory.SimpleFSIndexInput.html">SimpleFSDirectory.SimpleFSIndexInput</a></h4> |
| <section><p>Reads bytes with <span class="xref">System.IO.FileStream.Seek(System.Int64,System.IO.SeekOrigin)</span> followed by |
| <span class="xref">System.IO.FileStream.Read(System.Byte[],System.Int32,System.Int32)</span>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.SimpleFSLockFactory.html">SimpleFSLockFactory</a></h4> |
| <section><p>Implements <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> using |
| <span class="xref">System.IO.File.WriteAllText(System.String,System.String,System.Text.Encoding)</span> |
| (writes the file with UTF8 encoding and no byte order mark).</p> |
| |
| <p>Special care needs to be taken if you change the locking |
| implementation: First be certain that no writer is in fact |
| writing to the index otherwise you can easily corrupt |
| your index. Be sure to do the <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> change to all Lucene |
| instances and clean up all leftover lock files before starting |
| the new configuration for the first time. Different implementations |
| can not work together!</p> |
| |
| <p>If you suspect that this or any other <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> is |
| not working properly in your environment, you can easily |
| test it by using <a class="xref" href="Lucene.Net.Store.VerifyingLockFactory.html">VerifyingLockFactory</a>, |
| <a class="xref" href="Lucene.Net.Store.LockVerifyServer.html">LockVerifyServer</a> and <a class="xref" href="Lucene.Net.Store.LockStressTest.html">LockStressTest</a>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.SingleInstanceLockFactory.html">SingleInstanceLockFactory</a></h4> |
| <section><p>Implements <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> for a single in-process instance, |
| meaning all locking will take place through this one instance. |
| Only use this <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> when you are certain all |
| <a class="xref" href="Lucene.Net.Index.IndexReader.html">IndexReader</a>s and <a class="xref" href="Lucene.Net.Index.IndexWriter.html">IndexWriter</a>s for a given index are running |
| against a single shared in-process <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> instance. This is |
| currently the default locking for <a class="xref" href="Lucene.Net.Store.RAMDirectory.html">RAMDirectory</a>.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.TrackingDirectoryWrapper.html">TrackingDirectoryWrapper</a></h4> |
| <section><p>A delegating <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> that records which files were |
| written to and deleted.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Store.VerifyingLockFactory.html">VerifyingLockFactory</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> that wraps another |
| <a class="xref" href="Lucene.Net.Store.LockFactory.html">LockFactory</a> and verifies that each lock obtain/release |
| is "correct" (never results in two processes holding the |
| lock at the same time). It does this by contacting an |
| external server (<a class="xref" href="Lucene.Net.Store.LockVerifyServer.html">LockVerifyServer</a>) to assert that |
| at most one process holds the lock at a time. To use |
| this, you should also run <a class="xref" href="Lucene.Net.Store.LockVerifyServer.html">LockVerifyServer</a> on the |
| host & port matching what you pass to the constructor.</p> |
| </section> |
| <h3 id="enums">Enums |
| </h3> |
| <h4><a class="xref" href="Lucene.Net.Store.IOContext.UsageContext.html">IOContext.UsageContext</a></h4> |
| <section><p><a class="xref" href="Lucene.Net.Store.IOContext.UsageContext.html">IOContext.UsageContext</a> is a enumeration which specifies the context in which the <a class="xref" href="Lucene.Net.Store.Directory.html">Directory</a> |
| is being used for. |
| <p> |
| NOTE: This was Context in Lucene</p> |
| </section> |
| </article> |
| </div> |
| |
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