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| <h1 id="Lucene_Net_Util_Packed" data-uid="Lucene.Net.Util.Packed" class="text-break">Namespace Lucene.Net.Util.Packed |
| </h1> |
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| <h2 id="packed-integer-arrays-and-streams">Packed integer arrays and streams.</h2> |
| <p> The packed package provides * sequential and random access capable arrays of positive longs, * routines for efficient serialization and deserialization of streams of packed integers. The implementations provide different trade-offs between memory usage and access speed. The standard usage scenario is replacing large int or long arrays in order to reduce the memory footprint. </p> |
| <p> The main access point is the <xref:Lucene.Net.Util.Packed.PackedInts> factory. </p> |
| <h3 id="in-memory-structures">In-memory structures</h3> |
| <ul> |
| <li><p><strong><xref:Lucene.Net.Util.Packed.PackedInts.Mutable></strong></p> |
| <ul> |
| <li><p>Only supports positive longs.</p> |
| </li> |
| <li><p>Requires the number of bits per value to be known in advance.</p> |
| </li> |
| <li><p>Random-access for both writing and reading.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><a class="xref" href="Lucene.Net.Util.Packed.GrowableWriter.html">GrowableWriter</a></strong></p> |
| <ul> |
| <li><p>Same as PackedInts.Mutable but grows the number of bits per values when needed.</p> |
| </li> |
| <li><p>Useful to build a PackedInts.Mutable from a read-once stream of longs.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><a class="xref" href="Lucene.Net.Util.Packed.PagedGrowableWriter.html">PagedGrowableWriter</a></strong></p> |
| <ul> |
| <li><p>Slices data into fixed-size blocks stored in GrowableWriters.</p> |
| </li> |
| <li><p>Supports more than 2B values.</p> |
| </li> |
| <li><p>You should use Appending(Delta)PackedLongBuffer instead if you don't need random write access.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><xref:Lucene.Net.Util.Packed.AppendingDeltaPackedLongBuffer></strong></p> |
| <ul> |
| <li><p>Can store any sequence of longs.</p> |
| </li> |
| <li><p>Compression is good when values are close to each other.</p> |
| </li> |
| <li><p>Supports random reads, but only sequential writes.</p> |
| </li> |
| <li><p>Can address up to 2^42 values.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><xref:Lucene.Net.Util.Packed.AppendingPackedLongBuffer></strong></p> |
| <ul> |
| <li>Same as AppendingDeltaPackedLongBuffer but assumes values are 0-based.</li> |
| </ul> |
| </li> |
| <li><p><strong><xref:Lucene.Net.Util.Packed.MonotonicAppendingLongBuffer></strong></p> |
| <ul> |
| <li>Same as AppendingDeltaPackedLongBuffer except that compression is good when the stream is a succession of affine functions.</li> |
| </ul> |
| </li> |
| </ul> |
| <h3 id="disk-based-structures">Disk-based structures</h3> |
| <ul> |
| <li><p><strong><xref:Lucene.Net.Util.Packed.PackedInts.Writer>, <xref:Lucene.Net.Util.Packed.PackedInts.Reader>, <xref:Lucene.Net.Util.Packed.PackedInts.ReaderIterator></strong></p> |
| <ul> |
| <li><p>Only supports positive longs.</p> |
| </li> |
| <li><p>Requires the number of bits per value to be known in advance.</p> |
| </li> |
| <li><p>Supports both fast sequential access with low memory footprint with ReaderIterator and random-access by either loading values in memory or leaving them on disk with Reader.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><a class="xref" href="Lucene.Net.Util.Packed.BlockPackedWriter.html">BlockPackedWriter</a>, <a class="xref" href="Lucene.Net.Util.Packed.BlockPackedReader.html">BlockPackedReader</a>, <a class="xref" href="Lucene.Net.Util.Packed.BlockPackedReaderIterator.html">BlockPackedReaderIterator</a></strong></p> |
| <ul> |
| <li><p>Splits the stream into fixed-size blocks.</p> |
| </li> |
| <li><p>Compression is good when values are close to each other.</p> |
| </li> |
| <li><p>Can address up to 2B * blockSize values.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><a class="xref" href="Lucene.Net.Util.Packed.MonotonicBlockPackedWriter.html">MonotonicBlockPackedWriter</a>, <a class="xref" href="Lucene.Net.Util.Packed.MonotonicBlockPackedReader.html">MonotonicBlockPackedReader</a></strong></p> |
| <ul> |
| <li><p>Same as the non-monotonic variants except that compression is good when the stream is a succession of affine functions.</p> |
| </li> |
| <li><p>The reason why there is no sequential access is that if you need sequential access, you should rather delta-encode and use BlockPackedWriter.</p> |
| </li> |
| </ul> |
| </li> |
| <li><p><strong><a class="xref" href="Lucene.Net.Util.Packed.PackedDataOutput.html">PackedDataOutput</a>, <a class="xref" href="Lucene.Net.Util.Packed.PackedDataInput.html">PackedDataInput</a></strong></p> |
| <ul> |
| <li>Writes sequences of longs where each long can use any number of bits.</li> |
| </ul> |
| </li> |
| </ul> |
| </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.Util.Packed.AbstractAppendingInt64Buffer.html">AbstractAppendingInt64Buffer</a></h4> |
| <section><p>Common functionality shared by <a class="xref" href="Lucene.Net.Util.Packed.AppendingDeltaPackedInt64Buffer.html">AppendingDeltaPackedInt64Buffer</a> and <a class="xref" href="Lucene.Net.Util.Packed.MonotonicAppendingInt64Buffer.html">MonotonicAppendingInt64Buffer</a>. |
| <p> |
| NOTE: This was AbstractAppendingLongBuffer in Lucene</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.AbstractAppendingInt64Buffer.Iterator.html">AbstractAppendingInt64Buffer.Iterator</a></h4> |
| <section></section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.AbstractBlockPackedWriter.html">AbstractBlockPackedWriter</a></h4> |
| <section></section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.AbstractPagedMutable-1.html">AbstractPagedMutable<T></a></h4> |
| <section><p>Base implementation for <a class="xref" href="Lucene.Net.Util.Packed.PagedMutable.html">PagedMutable</a> and <a class="xref" href="Lucene.Net.Util.Packed.PagedGrowableWriter.html">PagedGrowableWriter</a>. |
| <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.Util.Packed.AppendingDeltaPackedInt64Buffer.html">AppendingDeltaPackedInt64Buffer</a></h4> |
| <section><p>Utility class to buffer a list of signed longs in memory. This class only |
| supports appending and is optimized for the case where values are close to |
| each other. |
| <p> |
| NOTE: This was AppendingDeltaPackedLongBuffer in Lucene |
| <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.Util.Packed.AppendingPackedInt64Buffer.html">AppendingPackedInt64Buffer</a></h4> |
| <section><p>Utility class to buffer a list of signed longs in memory. This class only |
| supports appending and is optimized for non-negative numbers with a uniform distribution over a fixed (limited) range. |
| <p> |
| NOTE: This was AppendingPackedLongBuffer in Lucene |
| <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.Util.Packed.BlockPackedReader.html">BlockPackedReader</a></h4> |
| <section><p>Provides random access to a stream written with <a class="xref" href="Lucene.Net.Util.Packed.BlockPackedWriter.html">BlockPackedWriter</a>. |
| <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.Util.Packed.BlockPackedReaderIterator.html">BlockPackedReaderIterator</a></h4> |
| <section><p>Reader for sequences of <span class="xref">System.Int64</span>s written with <a class="xref" href="Lucene.Net.Util.Packed.BlockPackedWriter.html">BlockPackedWriter</a>. |
| <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.Util.Packed.BlockPackedWriter.html">BlockPackedWriter</a></h4> |
| <section><p>A writer for large sequences of longs. |
| <p> |
| The sequence is divided into fixed-size blocks and for each block, the |
| difference between each value and the minimum value of the block is encoded |
| using as few bits as possible. Memory usage of this class is proportional to |
| the block size. Each block has an overhead between 1 and 10 bytes to store |
| the minimum value and the number of bits per value of the block. |
| <p> |
| Format: |
| <ul><li><BLock><sup>BlockCount</sup></li><li>BlockCount: ⌈ ValueCount / BlockSize ⌉</li><li>Block: <Header, (Ints)></li><li>Header: <Token, (MinValue)></li><li>Token: a byte (<a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteByte_System_Byte_">WriteByte(Byte)</a>), first 7 bits are the |
| number of bits per value (<code>bitsPerValue</code>). If the 8th bit is 1, |
| then MinValue (see next) is <code>0</code>, otherwise MinValue and needs to |
| be decoded</li><li>MinValue: a |
| <a href="https://developers.google.com/protocol-buffers/docs/encoding#types">zigzag-encoded</a> |
| variable-length <span class="xref">System.Int64</span> (<a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteVInt64_System_Int64_">WriteVInt64(Int64)</a>) whose value |
| should be added to every int from the block to restore the original |
| values</li><li>Ints: If the number of bits per value is <code>0</code>, then there is |
| nothing to decode and all ints are equal to MinValue. Otherwise: BlockSize |
| packed ints (<a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.html">PackedInt32s</a>) encoded on exactly <code>bitsPerValue</code> |
| bits per value. They are the subtraction of the original values and |
| MinValue</li></ul> |
| <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.Util.Packed.EliasFanoDecoder.html">EliasFanoDecoder</a></h4> |
| <section><p>A decoder for an <a class="xref" href="Lucene.Net.Util.Packed.EliasFanoEncoder.html">EliasFanoEncoder</a>. |
| <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.Util.Packed.EliasFanoDocIdSet.html">EliasFanoDocIdSet</a></h4> |
| <section><p>A DocIdSet in Elias-Fano encoding. |
| <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.Util.Packed.EliasFanoEncoder.html">EliasFanoEncoder</a></h4> |
| <section><p>Encode a non decreasing sequence of non negative whole numbers in the Elias-Fano encoding |
| that was introduced in the 1970's by Peter Elias and Robert Fano. |
| <p> |
| The Elias-Fano encoding is a high bits / low bits representation of |
| a monotonically increasing sequence of <code>numValues > 0</code> natural numbers <code>x[i]</code> |
| <p> |
| <code>0 <= x[0] <= x[1] <= ... <= x[numValues-2] <= x[numValues-1] <= upperBound</code> |
| <p> |
| where <code>upperBound > 0</code> is an upper bound on the last value. |
| <p> |
| The Elias-Fano encoding uses less than half a bit per encoded number more |
| than the smallest representation |
| that can encode any monotone sequence with the same bounds. |
| <p> |
| The lower <code>L</code> bits of each <code>x[i]</code> are stored explicitly and contiguously |
| in the lower-bits array, with <code>L</code> chosen as (<code>Log()</code> base 2): |
| <p> |
| <code>L = max(0, floor(log(upperBound/numValues)))</code> |
| <p> |
| The upper bits are stored in the upper-bits array as a sequence of unary-coded gaps (<code>x[-1] = 0</code>): |
| <p> |
| <code>(x[i]/2<strong>L) - (x[i-1]/2</strong>L)</code> |
| <p> |
| The unary code encodes a natural number <code>n</code> by <code>n</code> 0 bits followed by a 1 bit: |
| <code>0...01</code>. |
| <p> |
| In the upper bits the total the number of 1 bits is <code>numValues</code> |
| and the total number of 0 bits is: |
| <p> |
| <code>floor(x[numValues-1]/2<strong>L) <= upperBound/(2</strong>max(0, floor(log(upperBound/numValues)))) <= 2<em>numValues</em></code> |
| <p> |
| The Elias-Fano encoding uses at most |
| <p> |
| <code>2 + Ceil(Log(upperBound/numValues))</code> |
| <p> |
| bits per encoded number. With <code>upperBound</code> in these bounds (<code>p</code> is an integer): |
| <p> |
| <code>2<em>p < x[numValues-1] <= upperBound <= 2</em>*(p+1)</code> |
| <p> |
| the number of bits per encoded number is minimized. |
| <p> |
| In this implementation the values in the sequence can be given as <code>long</code>, |
| <code>numValues = 0</code> and <code>upperBound = 0</code> are allowed, |
| and each of the upper and lower bit arrays should fit in a <code>long[]</code>. |
| <p> |
| An index of positions of zero's in the upper bits is also built. |
| <p> |
| this implementation is based on this article: |
| <p> |
| Sebastiano Vigna, "Quasi Succinct Indices", June 19, 2012, sections 3, 4 and 9. |
| Retrieved from <a href="http://arxiv.org/pdf/1206.4300">http://arxiv.org/pdf/1206.4300</a> .</p> |
| <p><p>The articles originally describing the Elias-Fano representation are: |
| <p>Peter Elias, "Efficient storage and retrieval by content and address of static files", |
| J. Assoc. Comput. Mach., 21(2):246â€"260, 1974. |
| <p>Robert M. Fano, "On the number of bits required to implement an associative memory", |
| Memorandum 61, Computer Structures Group, Project MAC, MIT, Cambridge, Mass., 1971. |
| <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.Util.Packed.GrowableWriter.html">GrowableWriter</a></h4> |
| <section><p>Implements <a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.Mutable.html">PackedInt32s.Mutable</a>, but grows the |
| bit count of the underlying packed ints on-demand. |
| <p>Beware that this class will accept to set negative values but in order |
| to do this, it will grow the number of bits per value to 64. |
| <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.Util.Packed.MonotonicAppendingInt64Buffer.html">MonotonicAppendingInt64Buffer</a></h4> |
| <section><p>Utility class to buffer signed longs in memory, which is optimized for the |
| case where the sequence is monotonic, although it can encode any sequence of |
| arbitrary longs. It only supports appending. |
| <p> |
| NOTE: This was MonotonicAppendingLongBuffer in Lucene. |
| <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.Util.Packed.MonotonicBlockPackedReader.html">MonotonicBlockPackedReader</a></h4> |
| <section><p>Provides random access to a stream written with |
| <a class="xref" href="Lucene.Net.Util.Packed.MonotonicBlockPackedWriter.html">MonotonicBlockPackedWriter</a>. |
| <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.Util.Packed.MonotonicBlockPackedWriter.html">MonotonicBlockPackedWriter</a></h4> |
| <section><p>A writer for large monotonically increasing sequences of positive <span class="xref">System.Int64</span>s. |
| <p> |
| The sequence is divided into fixed-size blocks and for each block, values |
| are modeled after a linear function f: x → A × x + B. The block |
| encodes deltas from the expected values computed from this function using as |
| few bits as possible. Each block has an overhead between 6 and 14 bytes. |
| <p> |
| Format: |
| <ul><li><BLock><sup>BlockCount</sup></li><li>BlockCount: ⌈ ValueCount / BlockSize ⌉</li><li>Block: <Header, (Ints)></li><li>Header: <B, A, BitsPerValue></li><li>B: the B from f: x → A × x + B using a |
| variable-length <span class="xref">System.Int64</span> (<a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteVInt64_System_Int64_">WriteVInt64(Int64)</a>)</li><li>A: the A from f: x → A × x + B encoded using |
| <span class="xref">J2N.BitConversion.SingleToInt32Bits(System.Single)</span> on |
| 4 bytes (<a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteVInt32_System_Int32_">WriteVInt32(Int32)</a>)</li><li>BitsPerValue: a variable-length <span class="xref">System.Int32</span> (<a class="xref" href="Lucene.Net.Store.DataOutput.html#Lucene_Net_Store_DataOutput_WriteVInt32_System_Int32_">WriteVInt32(Int32)</a>)</li><li>Ints: if BitsPerValue is <code>0</code>, then there is nothing to read and |
| all values perfectly match the result of the function. Otherwise, these |
| are the |
| <a href="https://developers.google.com/protocol-buffers/docs/encoding#types">zigzag-encoded</a> |
| packed (<a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.html">PackedInt32s</a>) deltas from the expected value (computed from |
| the function) using exaclty BitsPerValue bits per value</li></ul> |
| <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.Util.Packed.Packed64.html">Packed64</a></h4> |
| <section><p>Space optimized random access capable array of values with a fixed number of |
| bits/value. Values are packed contiguously. |
| <p> |
| The implementation strives to perform af fast as possible under the |
| constraint of contiguous bits, by avoiding expensive operations. This comes |
| at the cost of code clarity. |
| <p> |
| Technical details: this implementation is a refinement of a non-branching |
| version. The non-branching get and set methods meant that 2 or 4 atomics in |
| the underlying array were always accessed, even for the cases where only |
| 1 or 2 were needed. Even with caching, this had a detrimental effect on |
| performance. |
| Related to this issue, the old implementation used lookup tables for shifts |
| and masks, which also proved to be a bit slower than calculating the shifts |
| and masks on the fly. |
| See <a href="https://issues.apache.org/jira/browse/LUCENE-4062">https://issues.apache.org/jira/browse/LUCENE-4062</a> for details.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedDataInput.html">PackedDataInput</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.DataInput.html">DataInput</a> wrapper to read unaligned, variable-length packed |
| integers. This API is much slower than the <a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.html">PackedInt32s</a> fixed-length |
| API but can be convenient to save space. |
| <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.Util.Packed.PackedDataOutput.html">PackedDataOutput</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Store.DataOutput.html">DataOutput</a> wrapper to write unaligned, variable-length packed |
| integers. |
| <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.Util.Packed.PackedInt32s.html">PackedInt32s</a></h4> |
| <section><p>Simplistic compression for array of unsigned long values. |
| Each value is >= 0 and <= a specified maximum value. The |
| values are stored as packed ints, with each value |
| consuming a fixed number of bits. |
| <p> |
| NOTE: This was PackedInts in Lucene. |
| <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.Util.Packed.PackedInt32s.Format.html">PackedInt32s.Format</a></h4> |
| <section><p>A format to write packed <span class="xref">System.Int32</span>s. |
| <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.Util.Packed.PackedInt32s.FormatAndBits.html">PackedInt32s.FormatAndBits</a></h4> |
| <section><p>Simple class that holds a format and a number of bits per value.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.Header.html">PackedInt32s.Header</a></h4> |
| <section><p>Header identifying the structure of a packed integer array. </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.Mutable.html">PackedInt32s.Mutable</a></h4> |
| <section><p>A packed integer array that can be modified. |
| <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.Util.Packed.PackedInt32s.MutableImpl.html">PackedInt32s.MutableImpl</a></h4> |
| <section></section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.NullReader.html">PackedInt32s.NullReader</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.Reader.html">PackedInt32s.Reader</a> which has all its values equal to 0 (bitsPerValue = 0). </p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.Reader.html">PackedInt32s.Reader</a></h4> |
| <section><p>A read-only random access array of positive integers. |
| <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.Util.Packed.PackedInt32s.Writer.html">PackedInt32s.Writer</a></h4> |
| <section><p>A write-once Writer. |
| <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.Util.Packed.PagedGrowableWriter.html">PagedGrowableWriter</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Util.Packed.PagedGrowableWriter.html">PagedGrowableWriter</a>. This class slices data into fixed-size blocks |
| which have independent numbers of bits per value and grow on-demand. |
| <p> |
| You should use this class instead of the <a class="xref" href="Lucene.Net.Util.Packed.AbstractAppendingInt64Buffer.html">AbstractAppendingInt64Buffer</a> related ones only when |
| you need random write-access. Otherwise this class will likely be slower and |
| less memory-efficient. |
| <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.Util.Packed.PagedMutable.html">PagedMutable</a></h4> |
| <section><p>A <a class="xref" href="Lucene.Net.Util.Packed.PagedMutable.html">PagedMutable</a>. This class slices data into fixed-size blocks |
| which have the same number of bits per value. It can be a useful replacement |
| for <a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.Mutable.html">PackedInt32s.Mutable</a> to store more than 2B values. |
| <p> |
| <div class="lucene-block lucene-internal">This is a Lucene.NET INTERNAL API, use at your own risk</div></section> |
| <h3 id="interfaces">Interfaces |
| </h3> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.IDecoder.html">PackedInt32s.IDecoder</a></h4> |
| <section><p>A decoder for packed integers.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.IEncoder.html">PackedInt32s.IEncoder</a></h4> |
| <section><p>An encoder for packed integers.</p> |
| </section> |
| <h4><a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.IReaderIterator.html">PackedInt32s.IReaderIterator</a></h4> |
| <section><p>Run-once iterator interface, to decode previously saved <a class="xref" href="Lucene.Net.Util.Packed.PackedInt32s.html">PackedInt32s</a>.</p> |
| </section> |
| </article> |
| </div> |
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