/*
* 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.util;
import java.io.IOException;
/**
* A simple iterator interface for {@link BytesRef} iteration.
*/
public interface BytesRefIterator {
/**
* Increments the iteration to the next {@link BytesRef} in the iterator.
* Returns the resulting {@link BytesRef} or <code>null</code> if the end of
* the iterator is reached. The returned BytesRef may be re-used across calls
* to next. After this method returns null, do not call it again: the results
* are undefined.
*
* @return the next {@link BytesRef} in the iterator or <code>null</code> if
* the end of the iterator is reached.
* @throws IOException If there is a low-level I/O error.
*/
public BytesRef next() throws IOException;
/** Singleton BytesRefIterator that iterates over 0 BytesRefs. */
public static final BytesRefIterator EMPTY = new BytesRefIterator() {
@Override
public BytesRef next() {
return null;
}
};
}