| /* |
| * 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.ko.dict; |
| |
| import java.io.IOException; |
| import org.apache.lucene.util.fst.FST; |
| import org.apache.lucene.util.fst.FST.Arc; |
| |
| /** Thin wrapper around an FST with root-arc caching for Hangul syllables (11,172 arcs). */ |
| public final class TokenInfoFST { |
| private final FST<Long> fst; |
| |
| private final int cacheCeiling; |
| private final FST.Arc<Long>[] rootCache; |
| |
| public final Long NO_OUTPUT; |
| |
| public TokenInfoFST(FST<Long> fst) throws IOException { |
| this.fst = fst; |
| this.cacheCeiling = 0xD7A3; |
| NO_OUTPUT = fst.outputs.getNoOutput(); |
| rootCache = cacheRootArcs(); |
| } |
| |
| @SuppressWarnings({"rawtypes", "unchecked"}) |
| private FST.Arc<Long>[] cacheRootArcs() throws IOException { |
| FST.Arc<Long>[] rootCache = new FST.Arc[1 + (cacheCeiling - 0xAC00)]; |
| FST.Arc<Long> firstArc = new FST.Arc<>(); |
| fst.getFirstArc(firstArc); |
| FST.Arc<Long> arc = new FST.Arc<>(); |
| final FST.BytesReader fstReader = fst.getBytesReader(); |
| // TODO: jump to AC00, readNextRealArc to ceiling? (just be careful we don't add bugs) |
| for (int i = 0; i < rootCache.length; i++) { |
| if (fst.findTargetArc(0xAC00 + i, firstArc, arc, fstReader) != null) { |
| rootCache[i] = new FST.Arc<Long>().copyFrom(arc); |
| } |
| } |
| return rootCache; |
| } |
| |
| public FST.Arc<Long> findTargetArc( |
| int ch, FST.Arc<Long> follow, FST.Arc<Long> arc, boolean useCache, FST.BytesReader fstReader) |
| throws IOException { |
| if (useCache && ch >= 0xAC00 && ch <= cacheCeiling) { |
| assert ch != FST.END_LABEL; |
| final Arc<Long> result = rootCache[ch - 0xAC00]; |
| if (result == null) { |
| return null; |
| } else { |
| arc.copyFrom(result); |
| return arc; |
| } |
| } else { |
| return fst.findTargetArc(ch, follow, arc, fstReader); |
| } |
| } |
| |
| public Arc<Long> getFirstArc(FST.Arc<Long> arc) { |
| return fst.getFirstArc(arc); |
| } |
| |
| public FST.BytesReader getBytesReader() { |
| return fst.getBytesReader(); |
| } |
| |
| /** @lucene.internal for testing only */ |
| FST<Long> getInternalFST() { |
| return fst; |
| } |
| } |