Exemplo n.º 1
0
        internal void  AddDocument(Document doc)
        {
            indexStream.WriteLong(fieldsStream.GetFilePointer());

            int storedCount = 0;

            foreach (Field field  in doc.Fields())
            {
                if (field.IsStored())
                {
                    storedCount++;
                }
            }
            fieldsStream.WriteVInt(storedCount);

            foreach (Field field in doc.Fields())
            {
                if (field.IsStored())
                {
                    fieldsStream.WriteVInt(fieldInfos.FieldNumber(field.Name()));

                    byte bits = 0;
                    if (field.IsTokenized())
                    {
                        bits |= 1;
                    }
                    fieldsStream.WriteByte(bits);

                    fieldsStream.WriteString(field.StringValue());
                }
            }
        }
        private TermInfo termInfo = new TermInfo(); // minimize consing

        /// <summary>Merge one term found in one or more segments. The array <code>smis</code>
        /// contains segments that are positioned at the same term. <code>N</code>
        /// is the number of cells in the array actually occupied.
        ///
        /// </summary>
        /// <param name="smis">array of segments
        /// </param>
        /// <param name="n">number of cells in the array actually occupied
        /// </param>
        private void  MergeTermInfo(SegmentMergeInfo[] smis, int n)
        {
            long freqPointer = freqOutput.GetFilePointer();
            long proxPointer = proxOutput.GetFilePointer();

            int df = AppendPostings(smis, n); // append posting data

            long skipPointer = WriteSkip();

            if (df > 0)
            {
                // add an entry to the dictionary with pointers to prox and freq files
                termInfo.Set(df, freqPointer, proxPointer, (int)(skipPointer - freqPointer));
                termInfosWriter.Add(smis[0].term, termInfo);
            }
        }
Exemplo n.º 3
0
        /// <summary>Copy the contents of the file with specified extension into the
        /// provided output stream. Use the provided buffer for moving data
        /// to reduce memory allocation.
        /// </summary>
        private void  CopyFile(FileEntry source, OutputStream os, byte[] buffer)
        {
            InputStream is_Renamed = null;

            try
            {
                long startPtr = os.GetFilePointer();

                is_Renamed = directory.OpenFile(source.file);
                long length    = is_Renamed.Length();
                long remainder = length;
                int  chunk     = buffer.Length;

                while (remainder > 0)
                {
                    int len = (int)System.Math.Min(chunk, remainder);
                    is_Renamed.ReadBytes(buffer, 0, len);
                    os.WriteBytes(buffer, len);
                    remainder -= len;
                }

                // Verify that remainder is 0
                if (remainder != 0)
                {
                    throw new System.IO.IOException("Non-zero remainder length after copying: " + remainder + " (id: " + source.file + ", length: " + length + ", buffer size: " + chunk + ")");
                }

                // Verify that the output length diff is equal to original file
                long endPtr = os.GetFilePointer();
                long diff   = endPtr - startPtr;
                if (diff != length)
                {
                    throw new System.IO.IOException("Difference in the output file offsets " + diff + " does not match the original file length " + length);
                }
            }
            finally
            {
                if (is_Renamed != null)
                {
                    is_Renamed.Close();
                }
            }
        }
Exemplo n.º 4
0
		/// <summary>Copy the contents of the file with specified extension into the
		/// provided output stream. Use the provided buffer for moving data
		/// to reduce memory allocation.
		/// </summary>
		private void  CopyFile(FileEntry source, OutputStream os, byte[] buffer)
		{
			InputStream is_Renamed = null;
			try
			{
				long startPtr = os.GetFilePointer();
				
				is_Renamed = directory.OpenFile(source.file);
				long length = is_Renamed.Length();
				long remainder = length;
				int chunk = buffer.Length;
				
				while (remainder > 0)
				{
					int len = (int) System.Math.Min(chunk, remainder);
					is_Renamed.ReadBytes(buffer, 0, len);
					os.WriteBytes(buffer, len);
					remainder -= len;
				}
				
				// Verify that remainder is 0
				if (remainder != 0)
					throw new System.IO.IOException("Non-zero remainder length after copying: " + remainder + " (id: " + source.file + ", length: " + length + ", buffer size: " + chunk + ")");
				
				// Verify that the output length diff is equal to original file
				long endPtr = os.GetFilePointer();
				long diff = endPtr - startPtr;
				if (diff != length)
					throw new System.IO.IOException("Difference in the output file offsets " + diff + " does not match the original file length " + length);
			}
			finally
			{
				if (is_Renamed != null)
					is_Renamed.Close();
			}
		}
Exemplo n.º 5
0
        /// <summary>Merge files with the extensions added up to now.
        /// All files with these extensions are combined sequentially into the
        /// compound stream. After successful merge, the source files
        /// are deleted.
        /// </summary>
        public void  Close()
        {
            if (merged)
            {
                throw new System.SystemException("Merge already performed");
            }

            if ((entries.Count == 0))
            {
                throw new System.SystemException("No entries to merge have been defined");
            }

            merged = true;

            // open the compound stream
            OutputStream os = null;

            try
            {
                os = directory.CreateFile(fileName);

                // Write the number of entries
                os.WriteVInt(entries.Count);

                // Write the directory with all offsets at 0.
                // Remember the positions of directory entries so that we can
                // adjust the offsets later
                System.Collections.IEnumerator it = entries.GetEnumerator();
                while (it.MoveNext())
                {
                    FileEntry fe = (FileEntry)it.Current;
                    fe.directoryOffset = os.GetFilePointer();
                    os.WriteLong(0);                     // for now
                    os.WriteString(fe.file);
                }

                // Open the files and copy their data into the stream.
                // Remeber the locations of each file's data section.
                byte[] buffer = new byte[1024];
                it = entries.GetEnumerator();
                while (it.MoveNext())
                {
                    FileEntry fe = (FileEntry)it.Current;
                    fe.dataOffset = os.GetFilePointer();
                    CopyFile(fe, os, buffer);
                }

                // Write the data offsets into the directory of the compound stream
                it = entries.GetEnumerator();
                while (it.MoveNext())
                {
                    FileEntry fe = (FileEntry)it.Current;
                    os.Seek(fe.directoryOffset);
                    os.WriteLong(fe.dataOffset);
                }

                // Close the output stream. Set the os to null before trying to
                // close so that if an exception occurs during the close, the
                // finally clause below will not attempt to close the stream
                // the second time.
                OutputStream tmp = os;
                os = null;
                tmp.Close();
            }
            finally
            {
                if (os != null)
                {
                    try
                    {
                        os.Close();
                    }
                    catch (System.IO.IOException)
                    {
                    }
                }
            }
        }
Exemplo n.º 6
0
        private void  WritePostings(Posting[] postings, System.String segment)
        {
            OutputStream      freq = null, prox = null;
            TermInfosWriter   tis              = null;
            TermVectorsWriter termVectorWriter = null;

            try
            {
                //open files for inverse index storage
                freq = directory.CreateFile(segment + ".frq");
                prox = directory.CreateFile(segment + ".prx");
                tis  = new TermInfosWriter(directory, segment, fieldInfos);
                TermInfo      ti           = new TermInfo();
                System.String currentField = null;

                for (int i = 0; i < postings.Length; i++)
                {
                    Posting posting = postings[i];

                    // add an entry to the dictionary with pointers to prox and freq files
                    ti.Set(1, freq.GetFilePointer(), prox.GetFilePointer(), -1);
                    tis.Add(posting.term, ti);

                    // add an entry to the freq file
                    int postingFreq = posting.freq;
                    if (postingFreq == 1)
                    {
                        // optimize freq=1
                        freq.WriteVInt(1);
                    }
                    // set low bit of doc num.
                    else
                    {
                        freq.WriteVInt(0);           // the document number
                        freq.WriteVInt(postingFreq); // frequency in doc
                    }

                    int   lastPosition = 0; // write positions
                    int[] positions    = posting.positions;
                    for (int j = 0; j < postingFreq; j++)
                    {
                        // use delta-encoding
                        int position = positions[j];
                        prox.WriteVInt(position - lastPosition);
                        lastPosition = position;
                    }
                    // check to see if we switched to a new Field
                    System.String termField = posting.term.Field();
                    if ((System.Object)currentField != (System.Object)termField)
                    {
                        // changing Field - see if there is something to save
                        currentField = termField;
                        FieldInfo fi = fieldInfos.FieldInfo(currentField);
                        if (fi.storeTermVector)
                        {
                            if (termVectorWriter == null)
                            {
                                termVectorWriter = new TermVectorsWriter(directory, segment, fieldInfos);
                                termVectorWriter.OpenDocument();
                            }
                            termVectorWriter.OpenField(currentField);
                        }
                        else if (termVectorWriter != null)
                        {
                            termVectorWriter.CloseField();
                        }
                    }
                    if (termVectorWriter != null && termVectorWriter.IsFieldOpen())
                    {
                        termVectorWriter.AddTerm(posting.term.Text(), postingFreq);
                    }
                }
                if (termVectorWriter != null)
                {
                    termVectorWriter.CloseDocument();
                }
            }
            finally
            {
                // make an effort to close all streams we can but remember and re-throw
                // the first exception encountered in this process
                System.IO.IOException keep = null;
                if (freq != null)
                {
                    try
                    {
                        freq.Close();
                    }
                    catch (System.IO.IOException e)
                    {
                        if (keep == null)
                        {
                            keep = e;
                        }
                    }
                }
                if (prox != null)
                {
                    try
                    {
                        prox.Close();
                    }
                    catch (System.IO.IOException e)
                    {
                        if (keep == null)
                        {
                            keep = e;
                        }
                    }
                }
                if (tis != null)
                {
                    try
                    {
                        tis.Close();
                    }
                    catch (System.IO.IOException e)
                    {
                        if (keep == null)
                        {
                            keep = e;
                        }
                    }
                }
                if (termVectorWriter != null)
                {
                    try
                    {
                        termVectorWriter.Close();
                    }
                    catch (System.IO.IOException e)
                    {
                        if (keep == null)
                        {
                            keep = e;
                        }
                    }
                }
                if (keep != null)
                {
                    throw new System.IO.IOException(keep.StackTrace);
                }
            }
        }