package org.apache.lucene.index;
/*
* 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.
*/
import java.io.IOException;
import org.apache.lucene.util.Bits; // javadocs
import org.apache.lucene.util.BytesRef;
/** Also iterates through positions. */
public abstract class DocsAndPositionsEnum extends DocsEnum {
/** Flag to pass to {@link TermsEnum#docsAndPositions(Bits,DocsAndPositionsEnum,int)}
* if you require offsets in the returned enum. */
public static final int FLAG_OFFSETS = 0x1;
/** Flag to pass to {@link TermsEnum#docsAndPositions(Bits,DocsAndPositionsEnum,int)}
* if you require payloads in the returned enum. */
public static final int FLAG_PAYLOADS = 0x2;
/** Sole constructor. (For invocation by subclass
* constructors, typically implicit.) */
protected DocsAndPositionsEnum() {
}
/** Returns the next position. You should only call this
* up to {@link DocsEnum#freq()} times else
* the behavior is not defined. If positions were not
* indexed this will return -1; this only happens if
* offsets were indexed and you passed needsOffset=true
* when pulling the enum. */
public abstract int nextPosition() throws IOException;
/** Returns start offset for the current position, or -1
* if offsets were not indexed. */
public abstract int startOffset() throws IOException;
/** Returns end offset for the current position, or -1 if
* offsets were not indexed. */
public abstract int endOffset() throws IOException;
/** Returns the payload at this position, or null if no
* payload was indexed. You should not modify anything
* (neither members of the returned BytesRef nor bytes
* in the byte[]). */
public abstract BytesRef getPayload() throws IOException;
}