/// <summary>
/// encodes an entry (bytes+(contexts)+(payload)+weight) to the provided writer
/// </summary>
protected internal virtual void Encode(OfflineSorter.ByteSequencesWriter writer, ByteArrayDataOutput output, sbyte[] buffer, BytesRef spare, BytesRef payload, HashSet <BytesRef> contexts, long weight)
{
int requiredLength = spare.Length + 8 + ((hasPayloads) ? 2 + payload.Length : 0);
if (hasContexts)
{
foreach (BytesRef ctx in contexts)
{
requiredLength += 2 + ctx.Length;
}
requiredLength += 2; // for length of contexts
}
if (requiredLength >= buffer.Length)
{
buffer = ArrayUtil.Grow(buffer, requiredLength);
}
output.Reset(buffer);
output.WriteBytes(spare.Bytes, spare.Offset, spare.Length);
if (hasContexts)
{
foreach (BytesRef ctx in contexts)
{
output.WriteBytes(ctx.Bytes, ctx.Offset, ctx.Length);
output.WriteShort((short)ctx.Length);
}
output.WriteShort((short)contexts.Count);
}
if (hasPayloads)
{
output.WriteBytes(payload.Bytes, payload.Offset, payload.Length);
output.WriteShort((short)payload.Length);
}
output.WriteLong(weight);
writer.Write(buffer, 0, output.Position);
}
public override void Build(IInputIterator iterator)
{
if (iterator.HasContexts)
{
throw new System.ArgumentException("this suggester doesn't support contexts");
}
string prefix = this.GetType().Name;
var directory = OfflineSorter.DefaultTempDir();
var tempInput = FileSupport.CreateTempFile(prefix, ".input", directory);
var tempSorted = FileSupport.CreateTempFile(prefix, ".sorted", directory);
hasPayloads = iterator.HasPayloads;
var writer = new OfflineSorter.ByteSequencesWriter(tempInput);
OfflineSorter.ByteSequencesReader reader = null;
var scratch = new BytesRef();
TokenStreamToAutomaton ts2a = TokenStreamToAutomaton;
bool success = false;
count = 0;
byte[] buffer = new byte[8];
try
{
var output = new ByteArrayDataOutput(buffer);
BytesRef surfaceForm;
while ((surfaceForm = iterator.Next()) != null)
{
ISet <IntsRef> paths = ToFiniteStrings(surfaceForm, ts2a);
maxAnalyzedPathsForOneInput = Math.Max(maxAnalyzedPathsForOneInput, paths.Count);
foreach (IntsRef path in paths)
{
Util.Fst.Util.ToBytesRef(path, scratch);
// length of the analyzed text (FST input)
if (scratch.Length > ushort.MaxValue - 2)
{
throw new System.ArgumentException("cannot handle analyzed forms > " + (ushort.MaxValue - 2) +
" in length (got " + scratch.Length + ")");
}
ushort analyzedLength = (ushort)scratch.Length;
// compute the required length:
// analyzed sequence + weight (4) + surface + analyzedLength (short)
int requiredLength = analyzedLength + 4 + surfaceForm.Length + 2;
BytesRef payload;
if (hasPayloads)
{
if (surfaceForm.Length > (ushort.MaxValue - 2))
{
throw new ArgumentException("cannot handle surface form > " + (ushort.MaxValue - 2) +
" in length (got " + surfaceForm.Length + ")");
}
payload = iterator.Payload;
// payload + surfaceLength (short)
requiredLength += payload.Length + 2;
}
else
{
payload = null;
}
buffer = ArrayUtil.Grow(buffer, requiredLength);
output.Reset(buffer);
output.WriteShort((short)analyzedLength);
output.WriteBytes(scratch.Bytes, scratch.Offset, scratch.Length);
output.WriteInt(EncodeWeight(iterator.Weight));
if (hasPayloads)
{
for (int i = 0; i < surfaceForm.Length; i++)
{
if (surfaceForm.Bytes[i] == PAYLOAD_SEP)
{
throw new ArgumentException(
"surface form cannot contain unit separator character U+001F; this character is reserved");
}
}
output.WriteShort((short)surfaceForm.Length);
output.WriteBytes(surfaceForm.Bytes, surfaceForm.Offset, surfaceForm.Length);
output.WriteBytes(payload.Bytes, payload.Offset, payload.Length);
}
else
{
output.WriteBytes(surfaceForm.Bytes, surfaceForm.Offset, surfaceForm.Length);
}
Debug.Assert(output.Position == requiredLength, output.Position + " vs " + requiredLength);
writer.Write(buffer, 0, output.Position);
}
count++;
}
writer.Dispose();
// Sort all input/output pairs (required by FST.Builder):
(new OfflineSorter(new AnalyzingComparator(hasPayloads))).Sort(tempInput, tempSorted);
// Free disk space:
tempInput.Delete();
reader = new OfflineSorter.ByteSequencesReader(tempSorted);
var outputs = new PairOutputs <long?, BytesRef>(PositiveIntOutputs.Singleton,
ByteSequenceOutputs.Singleton);
var builder = new Builder <PairOutputs <long?, BytesRef> .Pair>(FST.INPUT_TYPE.BYTE1, outputs);
// Build FST:
BytesRef previousAnalyzed = null;
BytesRef analyzed = new BytesRef();
BytesRef surface = new BytesRef();
IntsRef scratchInts = new IntsRef();
var input = new ByteArrayDataInput();
// Used to remove duplicate surface forms (but we
// still index the hightest-weight one). We clear
// this when we see a new analyzed form, so it cannot
// grow unbounded (at most 256 entries):
var seenSurfaceForms = new HashSet <BytesRef>();
var dedup = 0;
while (reader.Read(scratch))
{
input.Reset(scratch.Bytes, scratch.Offset, scratch.Length);
ushort analyzedLength = (ushort)input.ReadShort();
analyzed.Grow(analyzedLength + 2);
input.ReadBytes(analyzed.Bytes, 0, analyzedLength);
analyzed.Length = analyzedLength;
long cost = input.ReadInt();
surface.Bytes = scratch.Bytes;
if (hasPayloads)
{
surface.Length = (ushort)input.ReadShort();
surface.Offset = input.Position;
}
else
{
surface.Offset = input.Position;
surface.Length = scratch.Length - surface.Offset;
}
if (previousAnalyzed == null)
{
previousAnalyzed = new BytesRef();
previousAnalyzed.CopyBytes(analyzed);
seenSurfaceForms.Add(BytesRef.DeepCopyOf(surface));
}
else if (analyzed.Equals(previousAnalyzed))
{
dedup++;
if (dedup >= maxSurfaceFormsPerAnalyzedForm)
{
// More than maxSurfaceFormsPerAnalyzedForm
// dups: skip the rest:
continue;
}
if (seenSurfaceForms.Contains(surface))
{
continue;
}
seenSurfaceForms.Add(BytesRef.DeepCopyOf(surface));
}
else
{
dedup = 0;
previousAnalyzed.CopyBytes(analyzed);
seenSurfaceForms.Clear();
seenSurfaceForms.Add(BytesRef.DeepCopyOf(surface));
}
// TODO: I think we can avoid the extra 2 bytes when
// there is no dup (dedup==0), but we'd have to fix
// the exactFirst logic ... which would be sort of
// hairy because we'd need to special case the two
// (dup/not dup)...
// NOTE: must be byte 0 so we sort before whatever
// is next
analyzed.Bytes[analyzed.Offset + analyzed.Length] = 0;
analyzed.Bytes[analyzed.Offset + analyzed.Length + 1] = (byte)dedup;
analyzed.Length += 2;
Util.Fst.Util.ToIntsRef(analyzed, scratchInts);
//System.out.println("ADD: " + scratchInts + " -> " + cost + ": " + surface.utf8ToString());
if (!hasPayloads)
{
builder.Add(scratchInts, outputs.NewPair(cost, BytesRef.DeepCopyOf(surface)));
}
else
{
int payloadOffset = input.Position + surface.Length;
int payloadLength = scratch.Length - payloadOffset;
BytesRef br = new BytesRef(surface.Length + 1 + payloadLength);
Array.Copy(surface.Bytes, surface.Offset, br.Bytes, 0, surface.Length);
br.Bytes[surface.Length] = PAYLOAD_SEP;
Array.Copy(scratch.Bytes, payloadOffset, br.Bytes, surface.Length + 1, payloadLength);
br.Length = br.Bytes.Length;
builder.Add(scratchInts, outputs.NewPair(cost, br));
}
}
fst = builder.Finish();
//Util.dotToFile(fst, "/tmp/suggest.dot");
success = true;
}
finally
{
if (success)
{
IOUtils.Close(reader, writer);
}
else
{
IOUtils.CloseWhileHandlingException(reader, writer);
}
tempInput.Delete();
tempSorted.Delete();
}
}
/// <summary>
/// Parses a specific affix rule putting the result into the provided affix map
/// </summary>
/// <param name="affixes"> Map where the result of the parsing will be put </param>
/// <param name="header"> Header line of the affix rule </param>
/// <param name="reader"> BufferedReader to read the content of the rule from </param>
/// <param name="conditionPattern"> <seealso cref="String#format(String, Object...)"/> pattern to be used to generate the condition regex
/// pattern </param>
/// <param name="seenPatterns"> map from condition -> index of patterns, for deduplication. </param>
/// <exception cref="IOException"> Can be thrown while reading the rule </exception>
private void ParseAffix(SortedDictionary <string, IList <char?> > affixes, string header, TextReader reader, string conditionPattern, IDictionary <string, int?> seenPatterns, IDictionary <string, int?> seenStrips)
{
BytesRef scratch = new BytesRef();
StringBuilder sb = new StringBuilder();
string[] args = whitespacePattern.Split(header);
bool crossProduct = args[2].Equals("Y");
int numLines = int.Parse(args[3], CultureInfo.InvariantCulture);
affixData = ArrayUtil.Grow(affixData, (currentAffix << 3) + (numLines << 3));
ByteArrayDataOutput affixWriter = new ByteArrayDataOutput(affixData, currentAffix << 3, numLines << 3);
for (int i = 0; i < numLines; i++)
{
Debug.Assert(affixWriter.Position == currentAffix << 3);
string line = reader.ReadLine();
string[] ruleArgs = whitespacePattern.Split(line);
// from the manpage: PFX flag stripping prefix [condition [morphological_fields...]]
// condition is optional
if (ruleArgs.Length < 4)
{
throw new Exception("The affix file contains a rule with less than four elements: " + line /*, reader.LineNumber */);// LUCENENET TODO: LineNumberReader
}
char flag = flagParsingStrategy.ParseFlag(ruleArgs[1]);
string strip = ruleArgs[2].Equals("0") ? "" : ruleArgs[2];
string affixArg = ruleArgs[3];
char[] appendFlags = null;
int flagSep = affixArg.LastIndexOf('/');
if (flagSep != -1)
{
string flagPart = affixArg.Substring(flagSep + 1);
affixArg = affixArg.Substring(0, flagSep - 0);
if (aliasCount > 0)
{
flagPart = GetAliasValue(int.Parse(flagPart, CultureInfo.InvariantCulture));
}
appendFlags = flagParsingStrategy.ParseFlags(flagPart);
Array.Sort(appendFlags);
twoStageAffix = true;
}
// TODO: add test and fix zero-affix handling!
string condition = ruleArgs.Length > 4 ? ruleArgs[4] : ".";
// at least the gascon affix file has this issue
if (condition.StartsWith("[", StringComparison.Ordinal) && !condition.EndsWith("]", StringComparison.Ordinal))
{
condition = condition + "]";
}
// "dash hasn't got special meaning" (we must escape it)
if (condition.IndexOf('-') >= 0)
{
condition = condition.Replace("-", "\\-");
}
string regex;
if (".".Equals(condition))
{
regex = ".*"; // Zero condition is indicated by dot
}
else if (condition.Equals(strip))
{
regex = ".*"; // TODO: optimize this better:
// if we remove 'strip' from condition, we don't have to append 'strip' to check it...!
// but this is complicated...
}
else
{
regex = string.Format(CultureInfo.InvariantCulture, conditionPattern, condition);
}
// deduplicate patterns
int?patternIndex = seenPatterns.ContainsKey(regex) ? seenPatterns[regex] : null;
if (patternIndex == null)
{
patternIndex = patterns.Count;
if (patternIndex > short.MaxValue)
{
throw new System.NotSupportedException("Too many patterns, please report this to [email protected]");
}
seenPatterns[regex] = patternIndex;
CharacterRunAutomaton pattern = new CharacterRunAutomaton((new RegExp(regex, RegExp.NONE)).ToAutomaton());
patterns.Add(pattern);
}
int?stripOrd = seenStrips.ContainsKey(strip) ? seenStrips[strip] : null;
if (stripOrd == null)
{
stripOrd = seenStrips.Count;
seenStrips[strip] = stripOrd;
if (stripOrd > char.MaxValue)
{
throw new System.NotSupportedException("Too many unique strips, please report this to [email protected]");
}
}
if (appendFlags == null)
{
appendFlags = NOFLAGS;
}
EncodeFlags(scratch, appendFlags);
int appendFlagsOrd = flagLookup.Add(scratch);
if (appendFlagsOrd < 0)
{
// already exists in our hash
appendFlagsOrd = (-appendFlagsOrd) - 1;
}
else if (appendFlagsOrd > short.MaxValue)
{
// this limit is probably flexible, but its a good sanity check too
throw new System.NotSupportedException("Too many unique append flags, please report this to [email protected]");
}
affixWriter.WriteShort((short)flag);
affixWriter.WriteShort((short)stripOrd);
// encode crossProduct into patternIndex
int patternOrd = (int)patternIndex << 1 | (crossProduct ? 1 : 0);
affixWriter.WriteShort((short)patternOrd);
affixWriter.WriteShort((short)appendFlagsOrd);
if (needsInputCleaning)
{
string cleaned = CleanInput(affixArg, sb);
affixArg = cleaned.ToString();
}
IList <char?> list = affixes.ContainsKey(affixArg) ? affixes[affixArg] : null;
if (list == null)
{
list = new List <char?>();
affixes[affixArg] = list;
}
list.Add((char)currentAffix);
currentAffix++;
}
}