NormsProducer

java.lang.Object
- org.apache.lucene.codecs.NormsProducer

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

Direct Known Subclasses:

Lucene70NormsProducer, Lucene80NormsProducer, Lucene90NormsProducer, SimpleTextNormsFormat.SimpleTextNormsProducer
```
public abstract class NormsProducer
extends java.lang.Object
implements java.io.Closeable
```
Abstract API that produces field normalization values

Constructor Summary

Constructors
Modifier Constructor Description

protected NormsProducer()
Sole constructor.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`abstract void`	`checkIntegrity()`	Checks consistency of this producer
`NormsProducer`	`getMergeInstance()`	Returns an instance optimized for merging.
`abstract NumericDocValues`	`getNorms(FieldInfo field)`	Returns `NumericDocValues` for this field.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.io.Closeable
close

- Constructor Detail
  - NormsProducer
```
protected NormsProducer()
```
    Sole constructor. (For invocation by subclass constructors, typically implicit.)
- Method Detail
  - getNorms
```
public abstract NumericDocValues getNorms(FieldInfo field)
                                   throws java.io.IOException
```
    Returns NumericDocValues for this field. The returned instance need not be thread-safe: it will only be used by a single thread. The behavior is undefined if the given field doesn't have norms enabled on its FieldInfo. The return value is never null.
    
    Throws:
    
    java.io.IOException
  - checkIntegrity
```
public abstract void checkIntegrity()
                             throws java.io.IOException
```
    Checks consistency of this producer
    Note that this may be costly in terms of I/O, e.g. may involve computing a checksum value against large data files.
    
    Throws:
    
    java.io.IOException
  - getMergeInstance
```
public NormsProducer getMergeInstance()
```
    Returns an instance optimized for merging. This instance may only be used from the thread that acquires it.
    The default implementation returns this