org.apache.lucene.search.suggest

## Class DocumentValueSourceDictionary

- java.lang.Object
- - org.apache.lucene.search.suggest.DocumentDictionary
  - - org.apache.lucene.search.suggest.DocumentValueSourceDictionary

- All Implemented Interfaces:
    Dictionary

      public class DocumentValueSourceDictionary
      extends DocumentDictionary

  Dictionary with terms and optionally payload and optionally contexts information taken from stored fields in a Lucene index. Similar to `DocumentDictionary`, except it obtains the weight of the terms in a document based on a `LongValuesSource`.

  NOTE:
  - The term field has to be stored; if it is missing, the document is skipped.
  - The payload and contexts field are optional and are not required to be stored.

  In practice the `LongValuesSource` will likely be obtained using the lucene expression module. The following example shows how to create a `LongValuesSource` from a simple addition of two fields: `Expression expression = JavascriptCompiler.compile("f1 + f2"); SimpleBindings bindings = new SimpleBindings(); bindings.add(new SortField("f1", SortField.Type.LONG)); bindings.add(new SortField("f2", SortField.Type.LONG)); LongValuesSource valueSource = expression.getDoubleValuesSource(bindings).toLongValuesSource();`

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class org.apache.lucene.search.suggest.DocumentDictionary

      `DocumentDictionary.DocumentInputIterator`

  - ### Field Summary

    - ### Fields inherited from class org.apache.lucene.search.suggest.DocumentDictionary

      `contextsField, payloadField, reader`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `DocumentValueSourceDictionary(IndexReader reader, String field, LongValuesSource weightsValueSource)` Creates a new dictionary with the contents of the fields named `field` for the terms and uses the `weightsValueSource` supplied to determine the score.
    `DocumentValueSourceDictionary(IndexReader reader, String field, LongValuesSource weightsValueSource, String payload)` Creates a new dictionary with the contents of the fields named `field` for the terms, `payloadField` for the corresponding payloads and uses the `weightsValueSource` supplied to determine the score.
    `DocumentValueSourceDictionary(IndexReader reader, String field, LongValuesSource weightsValueSource, String payload, String contexts)` Creates a new dictionary with the contents of the fields named `field` for the terms, `payload` for the corresponding payloads, `contexts` for the associated contexts and uses the `weightsValueSource` supplied to determine the score.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `InputIterator` | `getEntryIterator()` Returns an iterator over all the entries

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

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

- - ### Constructor Detail

    - #### DocumentValueSourceDictionary

          public DocumentValueSourceDictionary(IndexReader reader,
                                               String field,
                                               LongValuesSource weightsValueSource,
                                               String payload,
                                               String contexts)

      Creates a new dictionary with the contents of the fields named `field` for the terms, `payload` for the corresponding payloads, `contexts` for the associated contexts and uses the `weightsValueSource` supplied to determine the score.

    - #### DocumentValueSourceDictionary

          public DocumentValueSourceDictionary(IndexReader reader,
                                               String field,
                                               LongValuesSource weightsValueSource,
                                               String payload)

      Creates a new dictionary with the contents of the fields named `field` for the terms, `payloadField` for the corresponding payloads and uses the `weightsValueSource` supplied to determine the score.

    - #### DocumentValueSourceDictionary

          public DocumentValueSourceDictionary(IndexReader reader,
                                               String field,
                                               LongValuesSource weightsValueSource)

      Creates a new dictionary with the contents of the fields named `field` for the terms and uses the `weightsValueSource` supplied to determine the score.

  - ### Method Detail

    - #### getEntryIterator

          public InputIterator getEntryIterator()
                                         throws IOException

      Description copied from interface: `Dictionary`
      Returns an iterator over all the entries
      Specified by:
        `getEntryIterator` in interface `Dictionary`
      Overrides:
        `getEntryIterator` in class `DocumentDictionary`
      Returns:
        Iterator
      Throws:
        `IOException`

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