01 package gate.creole.annic.apache.lucene.analysis;
02
03 /**
04 * Copyright 2004 The Apache Software Foundation
05 *
06 * Licensed under the Apache License, Version 2.0 (the "License");
07 * you may not use this file except in compliance with the License.
08 * You may obtain a copy of the License at
09 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19 import java.io.IOException;
20
21 /** A TokenStream enumerates the sequence of tokens, either from
22 fields of a document or from query text.
23 <p>
24 This is an abstract class. Concrete subclasses are:
25 <ul>
26 <li>{@link Tokenizer}, a TokenStream
27 whose input is a Reader; and
28 <li>{@link TokenFilter}, a TokenStream
29 whose input is another TokenStream.
30 </ul>
31 */
32
33 public abstract class TokenStream {
34 /** Returns the next token in the stream, or null at EOS. */
35 public abstract Token next() throws IOException;
36
37 /** Releases resources associated with this stream. */
38 public void close() throws IOException {}
39 }
|