org.apache.lucene.analysis.commongrams

## Class CommonGramsQueryFilter

- java.lang.Object
- - org.apache.lucene.util.AttributeSource
  - - org.apache.lucene.analysis.TokenStream
    - - org.apache.lucene.analysis.TokenFilter
      - - org.apache.lucene.analysis.commongrams.CommonGramsQueryFilter

All Implemented Interfaces:
  Closeable, AutoCloseable

    public final class CommonGramsQueryFilter
    extends TokenFilter

Wrap a CommonGramsFilter optimizing phrase queries by only returning single words when they are not a member of a bigram. Example:

- query input to CommonGramsFilter: "the rain in spain falls mainly"
- output of CommomGramsFilter/input to CommonGramsQueryFilter: |"the, "the-rain"|"rain" "rain-in"|"in, "in-spain"|"spain"|"falls"|"mainly"
- output of CommonGramsQueryFilter:"the-rain", "rain-in" ,"in-spain", "falls", "mainly"

### Nested Class Summary

### Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource

`AttributeSource.State`

### Field Summary

### Fields inherited from class org.apache.lucene.analysis.TokenFilter

`input`

### Fields inherited from class org.apache.lucene.analysis.TokenStream

`DEFAULT_TOKEN_ATTRIBUTE_FACTORY`

### Constructor Summary

Constructors
Constructor and Description
`CommonGramsQueryFilter(CommonGramsFilter input)` Constructs a new CommonGramsQueryFilter based on the provided CommomGramsFilter

### Method Summary

All Methods Instance Methods Concrete Methods
`boolean` `incrementToken()` Output bigrams whenever possible to optimize queries.
`boolean` `isGramType()` Convenience method to check if the current type is a gram type
`void` `reset()`

### Methods inherited from class org.apache.lucene.analysis.TokenFilter

`close, end`

### Methods inherited from class org.apache.lucene.util.AttributeSource

`addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString`

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

`clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

### Constructor Detail

#### CommonGramsQueryFilter

    public CommonGramsQueryFilter(CommonGramsFilter input)

Constructs a new CommonGramsQueryFilter based on the provided CommomGramsFilter

Parameters:
  `input` - CommonGramsFilter the QueryFilter will use

### Method Detail

#### reset

    public void reset()
               throws IOException

Overrides:
  `reset` in class `TokenFilter`
Throws:
  `IOException`

#### incrementToken

    public boolean incrementToken()
                           throws IOException

Output bigrams whenever possible to optimize queries. Only output unigrams when they are not a member of a bigram. Example:

- input: "the rain in spain falls mainly"
- output:"the-rain", "rain-in" ,"in-spain", "falls", "mainly"

Specified by:
  `incrementToken` in class `TokenStream`
Throws:
  `IOException`

#### isGramType

    public boolean isGramType()

Convenience method to check if the current type is a gram type

Returns:
  `true` if the current type is a gram type, `false` otherwise