| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.lucene.analysis.path; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.lucene.analysis.Tokenizer; |
| import org.apache.lucene.analysis.tokenattributes.CharTermAttribute; |
| import org.apache.lucene.analysis.tokenattributes.OffsetAttribute; |
| import org.apache.lucene.analysis.tokenattributes.PositionIncrementAttribute; |
| import org.apache.lucene.util.AttributeFactory; |
| |
| /** |
| * Tokenizer for domain-like hierarchies. |
| * <p> |
| * Take something like: |
| * |
| * <pre> |
| * www.site.co.uk |
| * </pre> |
| * |
| * and make: |
| * |
| * <pre> |
| * www.site.co.uk |
| * site.co.uk |
| * co.uk |
| * uk |
| * </pre> |
| * |
| */ |
| public class ReversePathHierarchyTokenizer extends Tokenizer { |
| |
| public ReversePathHierarchyTokenizer() { |
| this(DEFAULT_BUFFER_SIZE, DEFAULT_DELIMITER, DEFAULT_DELIMITER, DEFAULT_SKIP); |
| } |
| |
| public ReversePathHierarchyTokenizer(int skip) { |
| this(DEFAULT_BUFFER_SIZE, DEFAULT_DELIMITER, DEFAULT_DELIMITER, skip); |
| } |
| |
| public ReversePathHierarchyTokenizer(int bufferSize, char delimiter) { |
| this(bufferSize, delimiter, delimiter, DEFAULT_SKIP); |
| } |
| |
| public ReversePathHierarchyTokenizer(char delimiter, char replacement) { |
| this(DEFAULT_BUFFER_SIZE, delimiter, replacement, DEFAULT_SKIP); |
| } |
| |
| public ReversePathHierarchyTokenizer(int bufferSize, char delimiter, char replacement) { |
| this(bufferSize, delimiter, replacement, DEFAULT_SKIP); |
| } |
| |
| public ReversePathHierarchyTokenizer(char delimiter, int skip) { |
| this( DEFAULT_BUFFER_SIZE, delimiter, delimiter, skip); |
| } |
| |
| public ReversePathHierarchyTokenizer(char delimiter, char replacement, int skip) { |
| this(DEFAULT_BUFFER_SIZE, delimiter, replacement, skip); |
| } |
| |
| public ReversePathHierarchyTokenizer |
| (AttributeFactory factory, char delimiter, char replacement, int skip) { |
| this(factory, DEFAULT_BUFFER_SIZE, delimiter, replacement, skip); |
| } |
| |
| public ReversePathHierarchyTokenizer( int bufferSize, char delimiter, char replacement, int skip) { |
| this(DEFAULT_TOKEN_ATTRIBUTE_FACTORY, bufferSize, delimiter, replacement, skip); |
| } |
| public ReversePathHierarchyTokenizer |
| (AttributeFactory factory, int bufferSize, char delimiter, char replacement, int skip) { |
| super(factory); |
| if (bufferSize < 0) { |
| throw new IllegalArgumentException("bufferSize cannot be negative"); |
| } |
| if (skip < 0) { |
| throw new IllegalArgumentException("skip cannot be negative"); |
| } |
| termAtt.resizeBuffer(bufferSize); |
| this.delimiter = delimiter; |
| this.replacement = replacement; |
| this.skip = skip; |
| resultToken = new StringBuilder(bufferSize); |
| resultTokenBuffer = new char[bufferSize]; |
| delimiterPositions = new ArrayList<>(bufferSize/10); |
| } |
| |
| private static final int DEFAULT_BUFFER_SIZE = 1024; |
| public static final char DEFAULT_DELIMITER = '/'; |
| public static final int DEFAULT_SKIP = 0; |
| |
| private final char delimiter; |
| private final char replacement; |
| private final int skip; |
| |
| private final CharTermAttribute termAtt = addAttribute(CharTermAttribute.class); |
| private final OffsetAttribute offsetAtt = addAttribute(OffsetAttribute.class); |
| private final PositionIncrementAttribute posAtt = addAttribute(PositionIncrementAttribute.class); |
| |
| private int endPosition = 0; |
| private int finalOffset = 0; |
| private int skipped = 0; |
| private StringBuilder resultToken; |
| |
| private List<Integer> delimiterPositions; |
| private int delimitersCount = -1; |
| private char[] resultTokenBuffer; |
| |
| @Override |
| public final boolean incrementToken() throws IOException { |
| clearAttributes(); |
| if(delimitersCount == -1){ |
| int length = 0; |
| delimiterPositions.add(0); |
| while (true) { |
| int c = input.read(); |
| if( c < 0 ) { |
| break; |
| } |
| length++; |
| if( c == delimiter ) { |
| delimiterPositions.add(length); |
| resultToken.append(replacement); |
| } |
| else{ |
| resultToken.append((char)c); |
| } |
| } |
| delimitersCount = delimiterPositions.size(); |
| if( delimiterPositions.get(delimitersCount-1) < length ){ |
| delimiterPositions.add(length); |
| delimitersCount++; |
| } |
| if( resultTokenBuffer.length < resultToken.length() ){ |
| resultTokenBuffer = new char[resultToken.length()]; |
| } |
| resultToken.getChars(0, resultToken.length(), resultTokenBuffer, 0); |
| resultToken.setLength(0); |
| int idx = delimitersCount-1 - skip; |
| if (idx >= 0) { |
| // otherwise it's ok, because we will skip and return false |
| endPosition = delimiterPositions.get(idx); |
| } |
| finalOffset = correctOffset(length); |
| posAtt.setPositionIncrement(1); |
| } |
| else{ |
| posAtt.setPositionIncrement(0); |
| } |
| |
| while( skipped < delimitersCount-skip-1 ){ |
| int start = delimiterPositions.get(skipped); |
| termAtt.copyBuffer(resultTokenBuffer, start, endPosition - start); |
| offsetAtt.setOffset(correctOffset(start), correctOffset(endPosition)); |
| skipped++; |
| return true; |
| } |
| |
| return false; |
| } |
| |
| @Override |
| public final void end() throws IOException { |
| super.end(); |
| // set final offset |
| offsetAtt.setOffset(finalOffset, finalOffset); |
| } |
| |
| @Override |
| public void reset() throws IOException { |
| super.reset(); |
| resultToken.setLength(0); |
| finalOffset = 0; |
| endPosition = 0; |
| skipped = 0; |
| delimitersCount = -1; |
| delimiterPositions.clear(); |
| } |
| } |