Package org.apache.lucene.analysis.ngram

# Class EdgeNGramTokenizer

java.lang.Object
org.apache.lucene.util.AttributeSource
org.apache.lucene.analysis.TokenStream
org.apache.lucene.analysis.Tokenizer
org.apache.lucene.analysis.ngram.NGramTokenizer
org.apache.lucene.analysis.ngram.EdgeNGramTokenizer

All Implemented Interfaces:
  `Closeable`, `AutoCloseable`

public class EdgeNGramTokenizer extends NGramTokenizer
Tokenizes the input from an edge into n-grams of given size(s).

This `Tokenizer` create n-grams from the beginning edge of a input token.

As of Lucene 4.4, this class supports `pre-tokenization` and correctly handles supplementary characters.

## Nested Class Summary

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

`AttributeSource.State`

## Field Summary

Fields
Modifier and Type
Field
Description
`static final int`
`DEFAULT_MAX_GRAM_SIZE`
`static final int`
`DEFAULT_MIN_GRAM_SIZE`

### Fields inherited from class org.apache.lucene.analysis.ngram.NGramTokenizer

`DEFAULT_MAX_NGRAM_SIZE, DEFAULT_MIN_NGRAM_SIZE`

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

`input`

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

`DEFAULT_TOKEN_ATTRIBUTE_FACTORY`

## Constructor Summary

Constructors
Constructor
Description
`EdgeNGramTokenizer(int minGram, int maxGram)`
Creates EdgeNGramTokenizer that can generate n-grams in the sizes of the given range
`EdgeNGramTokenizer(AttributeFactory factory, int minGram, int maxGram)`
Creates EdgeNGramTokenizer that can generate n-grams in the sizes of the given range

## Method Summary

### Methods inherited from class org.apache.lucene.analysis.ngram.NGramTokenizer

`end, incrementToken, isTokenChar, reset`

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

`close, correctOffset, setReader, setReaderTestPoint`

### 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`

## Field Details

### DEFAULT_MAX_GRAM_SIZE

public static final int DEFAULT_MAX_GRAM_SIZE

See Also:
  - Constant Field Values

### DEFAULT_MIN_GRAM_SIZE

public static final int DEFAULT_MIN_GRAM_SIZE

See Also:
  - Constant Field Values

## Constructor Details

### EdgeNGramTokenizer

public EdgeNGramTokenizer(int minGram, int maxGram)
Creates EdgeNGramTokenizer that can generate n-grams in the sizes of the given range

Parameters:
  `minGram` - the smallest n-gram to generate
  `maxGram` - the largest n-gram to generate

### EdgeNGramTokenizer

public EdgeNGramTokenizer(AttributeFactory factory, int minGram, int maxGram)
Creates EdgeNGramTokenizer that can generate n-grams in the sizes of the given range

Parameters:
  `factory` - `AttributeFactory` to use
  `minGram` - the smallest n-gram to generate
  `maxGram` - the largest n-gram to generate