org.apache.lucene.codecs.compressing

## Class CompressingTermVectorsFormat

- java.lang.Object
- - org.apache.lucene.codecs.TermVectorsFormat
  - - org.apache.lucene.codecs.compressing.CompressingTermVectorsFormat

Direct Known Subclasses:
  Lucene42TermVectorsFormat

    public class CompressingTermVectorsFormat
    extends TermVectorsFormat

A `TermVectorsFormat` that compresses chunks of documents together in order to improve the compression ratio.

WARNING: This API is experimental and might change in incompatible ways in the next release.

### Constructor Summary

Constructors
Constructor and Description
`CompressingTermVectorsFormat(String formatName, String segmentSuffix, CompressionMode compressionMode, int chunkSize)` Create a new `CompressingTermVectorsFormat`.

### Method Summary

Methods
`String` `toString()`
`TermVectorsReader` `vectorsReader(Directory directory, SegmentInfo segmentInfo, FieldInfos fieldInfos, IOContext context)` Returns a `TermVectorsReader` to read term vectors.
`TermVectorsWriter` `vectorsWriter(Directory directory, SegmentInfo segmentInfo, IOContext context)` Returns a `TermVectorsWriter` to write term vectors.

### Methods inherited from class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

### Constructor Detail

#### CompressingTermVectorsFormat

    public CompressingTermVectorsFormat(String formatName,
                                String segmentSuffix,
                                CompressionMode compressionMode,
                                int chunkSize)

Create a new `CompressingTermVectorsFormat`.

`formatName` is the name of the format. This name will be used in the file formats to perform `codec header checks`.

The `compressionMode` parameter allows you to choose between compression algorithms that have various compression and decompression speeds so that you can pick the one that best fits your indexing and searching throughput. You should never instantiate two `CompressingTermVectorsFormat`s that have the same name but different `CompressionMode`s.

`chunkSize` is the minimum byte size of a chunk of documents. Higher values of `chunkSize` should improve the compression ratio but will require more memory at indexing time and might make document loading a little slower (depending on the size of your OS cache compared to the size of your index).

Parameters:
  `formatName` - the name of the `StoredFieldsFormat`
  `segmentSuffix` - a suffix to append to files created by this format
  `compressionMode` - the `CompressionMode` to use
  `chunkSize` - the minimum number of bytes of a single chunk of stored documents
See Also:
  `CompressionMode`

### Method Detail

#### vectorsReader

    public final TermVectorsReader vectorsReader(Directory directory,
                                  SegmentInfo segmentInfo,
                                  FieldInfos fieldInfos,
                                  IOContext context)
                                          throws IOException

Description copied from class: `TermVectorsFormat`
Returns a `TermVectorsReader` to read term vectors.

Specified by:
  `vectorsReader` in class `TermVectorsFormat`
Throws:
  `IOException`

#### vectorsWriter

    public final TermVectorsWriter vectorsWriter(Directory directory,
                                  SegmentInfo segmentInfo,
                                  IOContext context)
                                          throws IOException

Description copied from class: `TermVectorsFormat`
Returns a `TermVectorsWriter` to write term vectors.

Specified by:
  `vectorsWriter` in class `TermVectorsFormat`
Throws:
  `IOException`

#### toString

    public String toString()

Overrides:
  `toString` in class `Object`