Package org.apache.lucene.analysis.ja

# Class JapaneseCompletionFilter

java.lang.Object
org.apache.lucene.util.AttributeSource
org.apache.lucene.analysis.TokenStream
org.apache.lucene.analysis.TokenFilter
org.apache.lucene.analysis.ja.JapaneseCompletionFilter

All Implemented Interfaces:
  `Closeable`, `AutoCloseable`, `Unwrappable<TokenStream>`

public final class JapaneseCompletionFilter extends TokenFilter
A `TokenFilter` that adds Japanese romanized tokens to the term attribute. Also, this keeps original tokens (surface forms). Main usage of this filter is Query Auto-Completion.

Supported romanization systems: (modified) Hepburn-shiki, Kunrei-shiki (Nihon-shiki) and Wāpuro shiki.

This does not strictly comply with the romanization systems listed above, but tries to cover possible keystroke supported by various Input Methods. e.g.: Circumflex / Macron representing Chōonpu (長音符) are not supported.

The romanization behaviour changes according to its `JapaneseCompletionFilter.Mode`. The default mode is `JapaneseCompletionFilter.Mode.INDEX`.

Note: This filter must be applied AFTER half-width and full-width normalization. Please ensure that a width normalizer such as `CJKWidthCharFilter` or `CJKWidthFilter` is included in your analysis chain. IF THE WIDTH NORMALIZATION IS NOT PERFORMED, THIS DOES NOT WORK AS EXPECTED. See also: `JapaneseCompletionAnalyzer`.

## Nested Class Summary

Nested Classes
Modifier and Type
Class
Description
`static enum`
`JapaneseCompletionFilter.Mode`
Completion mode

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

`AttributeSource.State`

## Field Summary

Fields
Modifier and Type
Field
Description
`static final JapaneseCompletionFilter.Mode`
`DEFAULT_MODE`

### 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
Description
`JapaneseCompletionFilter(TokenStream input)`
Creates a new `JapaneseCompletionFilter` with default configurations
`JapaneseCompletionFilter(TokenStream input, JapaneseCompletionFilter.Mode mode)`
Creates a new `JapaneseCompletionFilter`

## Method Summary

Modifier and Type
Method
Description
`boolean`
`incrementToken()`
`void`
`reset()`

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

`close, end, unwrap`

### 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_MODE

public static final JapaneseCompletionFilter.Mode DEFAULT_MODE

## Constructor Details

### JapaneseCompletionFilter

public JapaneseCompletionFilter(TokenStream input)
Creates a new `JapaneseCompletionFilter` with default configurations

### JapaneseCompletionFilter

public JapaneseCompletionFilter(TokenStream input, JapaneseCompletionFilter.Mode mode)
Creates a new `JapaneseCompletionFilter`

## Method Details

### reset

public void reset() throws IOException

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

### incrementToken

public boolean incrementToken() throws IOException

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