Package org.apache.lucene.analysis.charfilter

Class BaseCharFilter

java.lang.Object

java.io.Reader

org.apache.lucene.analysis.CharFilter

org.apache.lucene.analysis.charfilter.BaseCharFilter

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

Direct Known Subclasses:

CJKWidthCharFilter, HTMLStripCharFilter, MappingCharFilter, PatternReplaceCharFilter

public abstract class BaseCharFilter
extends CharFilter

Base utility class for implementing a CharFilter. You subclass this, and then record mappings by calling addOffCorrectMap(int, int), and then invoke the correct method to correct an offset.

Field Summary

Fields inherited from class org.apache.lucene.analysis.CharFilter

input

Fields inherited from class java.io.Reader

lock

Constructor Summary

Constructors

Constructor	Description
BaseCharFilter(Reader in)

Method Summary

Modifier and Type	Method	Description
protected void	addOffCorrectMap(int off, int cumulativeDiff)	Adds an offset correction mapping at the given output stream offset.
protected int	correct(int currentOff)	Retrieve the corrected offset.
protected int	getLastCumulativeDiff()

Methods inherited from class org.apache.lucene.analysis.CharFilter

close, correctOffset

Methods inherited from class java.io.Reader

mark, markSupported, nullReader, read, read, read, read, ready, reset, skip, transferTo

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BaseCharFilter

public BaseCharFilter(Reader in)

Method Detail

correct

protected int correct(int currentOff)

Retrieve the corrected offset.

Specified by:

correct in class CharFilter

getLastCumulativeDiff

protected int getLastCumulativeDiff()

addOffCorrectMap

protected void addOffCorrectMap(int off,
                                int cumulativeDiff)

Adds an offset correction mapping at the given output stream offset.

Assumption: the offset given with each successive call to this method will not be smaller than the offset given at the previous invocation.

Parameters:

off - The output stream offset at which to apply the correction

cumulativeDiff - The input offset is given by adding this to the output offset