## org.apache.lucene.codecs
Class NormsFormat

    java.lang.Object
      org.apache.lucene.codecs.NormsFormat

Direct Known Subclasses:
  Lucene40NormsFormat, Lucene42NormsFormat

    public abstract class NormsFormat

extends Object

Encodes/decodes per-document score normalization values.

Constructor Summary
`protected` `NormsFormat()` Sole constructor.

Method Summary
`abstract DocValuesConsumer` `normsConsumer(SegmentWriteState state)` Returns a `DocValuesConsumer` to write norms to the index.
`abstract DocValuesProducer` `normsProducer(SegmentReadState state)` Returns a `DocValuesProducer` to read norms from the index.

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

Constructor Detail

### NormsFormat

    protected NormsFormat()

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

Method Detail

### normsConsumer

    public abstract DocValuesConsumer normsConsumer(SegmentWriteState state)
                                             throws IOException

  Returns a `DocValuesConsumer` to write norms to the index.

  Throws:
    `IOException`

### normsProducer

    public abstract DocValuesProducer normsProducer(SegmentReadState state)
                                             throws IOException

  Returns a `DocValuesProducer` to read norms from the index.

  NOTE: by the time this call returns, it must hold open any files it will need to use; else, those files may be deleted. Additionally, required files may be deleted during the execution of this call before there is a chance to open them. Under these circumstances an IOException should be thrown by the implementation. IOExceptions are expected and will automatically cause a retry of the segment opening logic with the newly revised segments.

  Throws:
    `IOException`

Copyright © 2000-2013 Apache Software Foundation. All Rights Reserved.