/**
* 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;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* A SinkTokenizer can be used to cache Tokens for use in an Analyzer
* <p/>
* WARNING: {@link TeeTokenFilter} and {@link SinkTokenizer} only work with the old TokenStream API.
* If you switch to the new API, you need to use {@link TeeSinkTokenFilter} instead, which offers
* the same functionality.
* @see TeeTokenFilter
* @deprecated Use {@link TeeSinkTokenFilter} instead
*
**/
public class SinkTokenizer extends Tokenizer {
protected List/*<Token>*/ lst = new ArrayList/*<Token>*/();
protected Iterator/*<Token>*/ iter;
public SinkTokenizer(List/*<Token>*/ input) {
this.lst = input;
if (this.lst == null) this.lst = new ArrayList/*<Token>*/();
}
public SinkTokenizer() {
this.lst = new ArrayList/*<Token>*/();
}
public SinkTokenizer(int initCap){
this.lst = new ArrayList/*<Token>*/(initCap);
}
/**
* Get the tokens in the internal List.
* <p/>
* WARNING: Adding tokens to this list requires the {@link #reset()} method to be called in order for them
* to be made available. Also, this Tokenizer does nothing to protect against {@link java.util.ConcurrentModificationException}s
* in the case of adds happening while {@link #next(org.apache.lucene.analysis.Token)} is being called.
* <p/>
* WARNING: Since this SinkTokenizer can be reset and the cached tokens made available again, do not modify them. Modify clones instead.
*
* @return A List of {@link org.apache.lucene.analysis.Token}s
*/
public List/*<Token>*/ getTokens() {
return lst;
}
/**
* Returns the next token out of the list of cached tokens
* @return The next {@link org.apache.lucene.analysis.Token} in the Sink.
* @throws IOException
*/
public Token next(final Token reusableToken) throws IOException {
assert reusableToken != null;
if (iter == null) iter = lst.iterator();
// Since this TokenStream can be reset we have to maintain the tokens as immutable
if (iter.hasNext()) {
Token nextToken = (Token) iter.next();
return (Token) nextToken.clone();
}
return null;
}
/**
* Override this method to cache only certain tokens, or new tokens based
* on the old tokens.
*
* @param t The {@link org.apache.lucene.analysis.Token} to add to the sink
*/
public void add(Token t) {
if (t == null) return;
lst.add((Token) t.clone());
}
public void close() throws IOException {
//nothing to close
input = null;
lst = null;
}
/**
* Reset the internal data structures to the start at the front of the list of tokens. Should be called
* if tokens were added to the list after an invocation of {@link #next(Token)}
* @throws IOException
*/
public void reset() throws IOException {
iter = lst.iterator();
}
}