Package org.apache.lucene.analysis.icu

# Class ICUTransformFilter

java.lang.Object
org.apache.lucene.util.AttributeSource
org.apache.lucene.analysis.TokenStream
org.apache.lucene.analysis.TokenFilter
org.apache.lucene.analysis.icu.ICUTransformFilter

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

public final class ICUTransformFilter extends TokenFilter
A `TokenFilter` that transforms text with ICU.

ICU provides text-transformation functionality via its Transliteration API. Although script conversion is its most common use, a Transliterator can actually perform a more general class of tasks. In fact, Transliterator defines a very general API which specifies only that a segment of the input text is replaced by new text. The particulars of this conversion are determined entirely by subclasses of Transliterator.

Some useful transformations for search are built-in:

- Conversion from Traditional to Simplified Chinese characters
- Conversion from Hiragana to Katakana
- Conversion from Fullwidth to Halfwidth forms.
- Script conversions, for example Serbian Cyrillic to Latin

Example usage:

> stream = new ICUTransformFilter(stream, Transliterator.getInstance("Traditional-Simplified"));

For more details, see the ICU User Guide.

## 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
Description
`ICUTransformFilter(TokenStream input, com.ibm.icu.text.Transliterator transform)`
Create a new ICUTransformFilter that transforms text on the given stream.

## Method Summary

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

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

`close, end, reset, 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`

## Constructor Details

### ICUTransformFilter

public ICUTransformFilter(TokenStream input, com.ibm.icu.text.Transliterator transform)
Create a new ICUTransformFilter that transforms text on the given stream.

Parameters:
  `input` - `TokenStream` to filter.
  `transform` - Transliterator to transform the text.

## Method Details

### incrementToken

public boolean incrementToken() throws IOException

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