Package org.apache.lucene.codecs

# Class FieldsProducer

java.lang.Object
org.apache.lucene.index.Fields
org.apache.lucene.codecs.FieldsProducer

All Implemented Interfaces:
  `Closeable`, `AutoCloseable`, `Iterable<String>`

Direct Known Subclasses:
  `Lucene103BlockTreeTermsReader`

public abstract class FieldsProducer extends Fields implements Closeable
Abstract API that produces terms, doc, freq, prox, offset and payloads postings.

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

- ## Field Summary

  ### Fields inherited from class org.apache.lucene.index.Fields

  `EMPTY_ARRAY`

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `FieldsProducer()`
  Sole constructor.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `abstract void`
  `checkIntegrity()`
  Checks consistency of this reader.
  `abstract void`
  `close()`
  `FieldsProducer`
  `getMergeInstance()`
  Returns an instance optimized for merging.

  ### Methods inherited from class org.apache.lucene.index.Fields

  `iterator, size, terms`

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

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

  ### Methods inherited from interface java.lang.Iterable

  `forEach, spliterator`

- ## Constructor Details

  - ### FieldsProducer

    protected FieldsProducer()
    Sole constructor. (For invocation by subclass constructors, typically implicit.)

- ## Method Details

  - ### close

    public abstract void close() throws IOException
    Specified by:
      `close` in interface `AutoCloseable`
    Specified by:
      `close` in interface `Closeable`
    Throws:
      `IOException`

  - ### checkIntegrity

    public abstract void checkIntegrity() throws IOException
    Checks consistency of this reader.

    Note that this may be costly in terms of I/O, e.g. may involve computing a checksum value against large data files.

    Throws:
      `IOException`
    NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

  - ### getMergeInstance

    public FieldsProducer getMergeInstance()
    Returns an instance optimized for merging. This instance may only be consumed in the thread that called `getMergeInstance()`.

    The default implementation returns `this`