FieldsProducer (Lucene 9.0.0 core API)

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

All Implemented Interfaces:

Closeable, AutoCloseable, Iterable<String>

Direct Known Subclasses:

Lucene90BlockTreeTermsReader
```
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

All Methods Instance Methods Abstract Methods Concrete Methods
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 Detail
  - FieldsProducer
```
protected FieldsProducer()
```
    Sole constructor. (For invocation by subclass constructors, typically implicit.)
- Method Detail
  - 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