All Known Implementing Classes:

AssociationEnhancement
```
public interface CategoryEnhancement
```
This interface allows easy addition of enhanced category features. Usually, a CategoryEnhancement will correspond to a CategoryProperty.
A category enhancement can contribute to the index in two possible ways:
1. To each category with data relevant to the enhancement, add this data to the category's token payload, through getCategoryTokenBytes(CategoryAttribute). This data will be read during search using extractCategoryTokenData(byte[], int, int).
2. To each document which contains categories with data relevant to the enhancement, add a CategoryListTokenizer through getCategoryListTokenizer(TokenStream, EnhancementsIndexingParams, TaxonomyWriter) . The CategoryListTokenizer should add a single token which includes all the enhancement relevant data from the categories. The category list token's text is defined by getCategoryListTermText().
WARNING: This API is experimental and might change in incompatible ways in the next release.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`equals(Object o)`	Category enhancements must override `Object.equals(Object)`, as it is used in `EnhancementsPayloadIterator.getCategoryData(CategoryEnhancement)`.
`Object`	`extractCategoryTokenData(byte[] buffer, int offset, int length)`	Get the data of this enhancement from a category token payload.
`boolean`	`generatesCategoryList()`	Declarative method to indicate whether this enhancement generates separate category list.
`String`	`getCategoryListTermText()`	Returns the text of this enhancement's category list term.
`CategoryListTokenizer`	`getCategoryListTokenizer(org.apache.lucene.analysis.TokenStream tokenizer, EnhancementsIndexingParams indexingParams, TaxonomyWriter taxonomyWriter)`	Get the `CategoryListTokenizer` which generates the category list for this enhancement.
`byte[]`	`getCategoryTokenBytes(CategoryAttribute categoryAttribute)`	Get the bytes to be added to the category token payload for this enhancement.
`Class<? extends CategoryProperty>`	`getRetainableProperty()`	Get a `CategoryProperty` class to be retained when creating `CategoryParentsStream`.

- Method Detail
  - getCategoryTokenBytes
```
byte[] getCategoryTokenBytes(CategoryAttribute categoryAttribute)
```
    Get the bytes to be added to the category token payload for this enhancement.
    NOTE: The returned array is copied, it is recommended to allocate a new one each time.
    The bytes generated by this method are the input of extractCategoryTokenData(byte[], int, int).
    
    Parameters:
    
    categoryAttribute - The attribute of the category.
    
    Returns:
    
    The bytes to be added to the category token payload for this enhancement.
  - extractCategoryTokenData
```
Object extractCategoryTokenData(byte[] buffer,
                                int offset,
                                int length)
```
    Get the data of this enhancement from a category token payload.
    The input bytes for this method are generated in getCategoryTokenBytes(CategoryAttribute).
    
    Parameters:
    
    buffer - The payload buffer.
    
    offset - The offset of this enhancement's data in the buffer.
    
    length - The length of this enhancement's data (bytes).
    
    Returns:
    
    An Object containing the data.
  - generatesCategoryList
```
boolean generatesCategoryList()
```
    Declarative method to indicate whether this enhancement generates separate category list.
    
    Returns:
    
    true if generates category list, else false.
  - getCategoryListTermText
```
String getCategoryListTermText()
```
    Returns the text of this enhancement's category list term.
    
    Returns:
    
    The text of this enhancement's category list term.
  - getCategoryListTokenizer
```
CategoryListTokenizer getCategoryListTokenizer(org.apache.lucene.analysis.TokenStream tokenizer,
                                               EnhancementsIndexingParams indexingParams,
                                               TaxonomyWriter taxonomyWriter)
```
    Get the CategoryListTokenizer which generates the category list for this enhancement. If generatesCategoryList() returns false this method will not be called.
    
    Parameters:
    
    tokenizer - The input stream containing categories.
    
    indexingParams - The indexing params to use.
    
    taxonomyWriter - The taxonomy to add categories and get their ordinals.
    
    Returns:
    
    A CategoryListTokenizer generating the category list for this enhancement, with tokenizer as it's input.
  - getRetainableProperty
```
Class<? extends CategoryProperty> getRetainableProperty()
```
    Get a CategoryProperty class to be retained when creating CategoryParentsStream.
    
    Returns:
    
    the CategoryProperty class to be retained when creating CategoryParentsStream, or null if there is no such property.
  - equals
```
boolean equals(Object o)
```
    Category enhancements must override Object.equals(Object), as it is used in EnhancementsPayloadIterator.getCategoryData(CategoryEnhancement).
    
    Overrides:
    
    equals in class Object

Interface CategoryEnhancement

Method Summary

Method Detail

getCategoryTokenBytes

extractCategoryTokenData

generatesCategoryList

getCategoryListTermText

getCategoryListTokenizer

getRetainableProperty

equals