org.apache.lucene.codecs.uniformsplit.sharedterms

## Class STUniformSplitTermsWriter

- java.lang.Object
- - org.apache.lucene.codecs.FieldsConsumer
  - - org.apache.lucene.codecs.uniformsplit.UniformSplitTermsWriter
    - - org.apache.lucene.codecs.uniformsplit.sharedterms.STUniformSplitTermsWriter

- All Implemented Interfaces:
    Closeable, AutoCloseable

      public class STUniformSplitTermsWriter
      extends UniformSplitTermsWriter

  Extends `UniformSplitTermsWriter` by sharing all the fields terms in the same dictionary and by writing all the fields of a term in the same block line.

  The `block file` contains all the term blocks for all fields. Each block line, for a single term, may have multiple fields `TermState`. The block file also contains the fields metadata at the end of the file.

  The `dictionary file` contains a single trie (`FST` bytes) for all fields.

  This structure is adapted when there are lots of fields. In this case the shared-terms dictionary trie is much smaller.

  This `FieldsConsumer` requires a custom `merge(MergeState, NormsProducer)` method for efficiency. The regular merge would scan all the fields sequentially, which internally would scan the whole shared-terms dictionary as many times as there are fields. Whereas the custom merge directly scans the internal shared-terms dictionary of all segments to merge, thus scanning once whatever the number of fields is.

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

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and Description
    --- | ---
    `protected class` | `STUniformSplitTermsWriter.SegmentPostings`

  - ### Field Summary

    - ### Fields inherited from class org.apache.lucene.codecs.uniformsplit.UniformSplitTermsWriter

      `blockEncoder, blockOutput, DEFAULT_DELTA_NUM_LINES, DEFAULT_TARGET_NUM_BLOCK_LINES, deltaNumLines, dictionaryOutput, fieldInfos, MAX_NUM_BLOCK_LINES, maxDoc, postingsWriter, targetNumBlockLines`

  - ### Constructor Summary

    Constructors
    Modifier | Constructor and Description
    --- | ---
    `` | `STUniformSplitTermsWriter(PostingsWriterBase postingsWriter, SegmentWriteState state, BlockEncoder blockEncoder)`
    `` | `STUniformSplitTermsWriter(PostingsWriterBase postingsWriter, SegmentWriteState state, int targetNumBlockLines, int deltaNumLines, BlockEncoder blockEncoder)`
    `protected` | `STUniformSplitTermsWriter(PostingsWriterBase postingsWriter, SegmentWriteState state, int targetNumBlockLines, int deltaNumLines, BlockEncoder blockEncoder, String codecName, int versionCurrent, String termsBlocksExtension, String dictionaryExtension)`

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `merge(MergeState mergeState, NormsProducer normsProducer)`
    `void` | `write(Fields fields, NormsProducer normsProducer)`
    `protected void` | `writeDictionary(int fieldsNumber, IndexDictionary.Builder dictionaryBuilder)`

    - ### Methods inherited from class org.apache.lucene.codecs.uniformsplit.UniformSplitTermsWriter

      `close, validateSettings, writeDictionary, writeFieldsMetadata, writeFieldTerms, writePostingLine`

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

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

- - ### Constructor Detail

    - #### STUniformSplitTermsWriter

          public STUniformSplitTermsWriter(PostingsWriterBase postingsWriter,
                                           SegmentWriteState state,
                                           BlockEncoder blockEncoder)
                                    throws IOException

      Throws:
        `IOException`

    - #### STUniformSplitTermsWriter

          public STUniformSplitTermsWriter(PostingsWriterBase postingsWriter,
                                           SegmentWriteState state,
                                           int targetNumBlockLines,
                                           int deltaNumLines,
                                           BlockEncoder blockEncoder)
                                    throws IOException

      Throws:
        `IOException`

    - #### STUniformSplitTermsWriter

          protected STUniformSplitTermsWriter(PostingsWriterBase postingsWriter,
                                              SegmentWriteState state,
                                              int targetNumBlockLines,
                                              int deltaNumLines,
                                              BlockEncoder blockEncoder,
                                              String codecName,
                                              int versionCurrent,
                                              String termsBlocksExtension,
                                              String dictionaryExtension)
                                       throws IOException

      Throws:
        `IOException`

  - ### Method Detail

    - #### write

          public void write(Fields fields,
                            NormsProducer normsProducer)
                     throws IOException

      Overrides:
        `write` in class `UniformSplitTermsWriter`
      Throws:
        `IOException`

    - #### writeDictionary

          protected void writeDictionary(int fieldsNumber,
                                         IndexDictionary.Builder dictionaryBuilder)
                                  throws IOException

      Throws:
        `IOException`

    - #### merge

          public void merge(MergeState mergeState,
                            NormsProducer normsProducer)
                     throws IOException

      Overrides:
        `merge` in class `FieldsConsumer`
      Throws:
        `IOException`

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