| using Lucene.Net.Diagnostics; |
| using Lucene.Net.Support; |
| using System; |
| using System.Runtime.CompilerServices; |
| |
| namespace Lucene.Net.Util.Packed |
| { |
| /* |
| * 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 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| using DataOutput = Lucene.Net.Store.DataOutput; |
| |
| public abstract class AbstractBlockPackedWriter // LUCENENET NOTE: made public rather than internal because has public subclasses |
| { |
| internal const int MIN_BLOCK_SIZE = 64; |
| internal const int MAX_BLOCK_SIZE = 1 << (30 - 3); |
| internal const int MIN_VALUE_EQUALS_0 = 1 << 0; |
| internal const int BPV_SHIFT = 1; |
| |
| [MethodImpl(MethodImplOptions.AggressiveInlining)] |
| internal static long ZigZagEncode(long n) |
| { |
| return (n >> 63) ^ (n << 1); |
| } |
| |
| // same as DataOutput.WriteVInt64 but accepts negative values |
| /// <summary> |
| /// NOTE: This was writeVLong() in Lucene. |
| /// </summary> |
| [MethodImpl(MethodImplOptions.AggressiveInlining)] |
| internal static void WriteVInt64(DataOutput @out, long i) |
| { |
| int k = 0; |
| while ((i & ~0x7FL) != 0L && k++ < 8) |
| { |
| @out.WriteByte((byte)((i & 0x7FL) | 0x80L)); |
| i = (long)((ulong)i >> 7); |
| } |
| @out.WriteByte((byte)i); |
| } |
| |
| protected DataOutput m_out; |
| protected readonly long[] m_values; |
| protected byte[] m_blocks; |
| protected int m_off; |
| protected long m_ord; |
| protected bool m_finished; |
| |
| /// <summary> |
| /// Sole constructor. </summary> |
| /// <param name="blockSize"> the number of values of a single block, must be a multiple of <c>64</c>. </param> |
| protected AbstractBlockPackedWriter(DataOutput @out, int blockSize) // LUCENENET specific - marked protected instead of public |
| { |
| PackedInt32s.CheckBlockSize(blockSize, MIN_BLOCK_SIZE, MAX_BLOCK_SIZE); |
| Reset(@out); |
| m_values = new long[blockSize]; |
| } |
| |
| /// <summary> |
| /// Reset this writer to wrap <paramref name="out"/>. The block size remains unchanged. </summary> |
| [MethodImpl(MethodImplOptions.AggressiveInlining)] |
| public virtual void Reset(DataOutput @out) |
| { |
| if (Debugging.AssertsEnabled) Debugging.Assert(@out != null); |
| this.m_out = @out; |
| m_off = 0; |
| m_ord = 0L; |
| m_finished = false; |
| } |
| |
| [MethodImpl(MethodImplOptions.AggressiveInlining)] |
| private void CheckNotFinished() |
| { |
| if (m_finished) |
| { |
| throw new InvalidOperationException("Already finished"); |
| } |
| } |
| |
| /// <summary> |
| /// Append a new long. </summary> |
| public virtual void Add(long l) |
| { |
| CheckNotFinished(); |
| if (m_off == m_values.Length) |
| { |
| Flush(); |
| } |
| m_values[m_off++] = l; |
| ++m_ord; |
| } |
| |
| // For testing only |
| internal virtual void AddBlockOfZeros() |
| { |
| CheckNotFinished(); |
| if (m_off != 0 && m_off != m_values.Length) |
| { |
| throw new InvalidOperationException("" + m_off); |
| } |
| if (m_off == m_values.Length) |
| { |
| Flush(); |
| } |
| Arrays.Fill(m_values, 0); |
| m_off = m_values.Length; |
| m_ord += m_values.Length; |
| } |
| |
| /// <summary> |
| /// Flush all buffered data to disk. This instance is not usable anymore |
| /// after this method has been called until <see cref="Reset(DataOutput)"/> has |
| /// been called. |
| /// </summary> |
| public virtual void Finish() |
| { |
| CheckNotFinished(); |
| if (m_off > 0) |
| { |
| Flush(); |
| } |
| m_finished = true; |
| } |
| |
| /// <summary> |
| /// Return the number of values which have been added. </summary> |
| public virtual long Ord => m_ord; |
| |
| [MethodImpl(MethodImplOptions.NoInlining)] |
| protected abstract void Flush(); |
| |
| protected void WriteValues(int bitsRequired) |
| { |
| PackedInt32s.IEncoder encoder = PackedInt32s.GetEncoder(PackedInt32s.Format.PACKED, PackedInt32s.VERSION_CURRENT, bitsRequired); |
| int iterations = m_values.Length / encoder.ByteValueCount; |
| int blockSize = encoder.ByteBlockCount * iterations; |
| if (m_blocks == null || m_blocks.Length < blockSize) |
| { |
| m_blocks = new byte[blockSize]; |
| } |
| if (m_off < m_values.Length) |
| { |
| Arrays.Fill(m_values, m_off, m_values.Length, 0L); |
| } |
| encoder.Encode(m_values, 0, m_blocks, 0, iterations); |
| int blockCount = (int)PackedInt32s.Format.PACKED.ByteCount(PackedInt32s.VERSION_CURRENT, m_off, bitsRequired); |
| m_out.WriteBytes(m_blocks, blockCount); |
| } |
| } |
| } |