com.browseengine.bobo.search.section.SectionSearchQueryPlan.java Source code

Introduction

Here is the source code for com.browseengine.bobo.search.section.SectionSearchQueryPlan.java

Source

/**
 * This software is licensed to you under the Apache License, Version 2.0 (the
 * "Apache License").
 *
 * LinkedIn's contributions are made under the Apache License. If you contribute
 * to the Software, the contributions will be deemed to have been made under the
 * Apache License, unless you expressly indicate otherwise. Please do not make any
 * contributions that would be inconsistent with the Apache License.
 *
 * You may obtain a copy of the Apache License at http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, this software
 * distributed under the Apache License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the Apache
 * License for the specific language governing permissions and limitations for the
 * software governed under the Apache License.
 *
 *  2012 LinkedIn Corp. All Rights Reserved.  
 */

package com.browseengine.bobo.search.section;

import java.io.IOException;

import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.util.PriorityQueue;

/**
 * This class represents a section search query plan
 *
 */
public abstract class SectionSearchQueryPlan {
    public static final int NO_MORE_POSITIONS = Integer.MAX_VALUE;
    public static final int NO_MORE_SECTIONS = Integer.MAX_VALUE;

    protected int _curDoc;
    protected int _curSec;

    /*
     * Priority queue of Nodes.
     */
    static public class NodeQueue extends PriorityQueue {
        public NodeQueue(int size) {
            initialize(size);
        }

        protected boolean lessThan(Object objA, Object objB) {
            SectionSearchQueryPlan nodeA = (SectionSearchQueryPlan) objA;
            SectionSearchQueryPlan nodeB = (SectionSearchQueryPlan) objB;
            if (nodeA._curDoc == nodeB._curDoc) {
                return (nodeA._curSec < nodeB._curSec);
            }
            return (nodeA._curDoc < nodeB._curDoc);
        }
    }

    public SectionSearchQueryPlan() {
        _curDoc = -1;
        _curSec = -1;
    }

    public int getDocId() {
        return _curDoc;
    }

    public int getSecId() {
        return _curSec;
    }

    public int fetch(int targetDoc) throws IOException {
        while (fetchDoc(targetDoc) < DocIdSetIterator.NO_MORE_DOCS) {
            if (fetchSec(0) < SectionSearchQueryPlan.NO_MORE_SECTIONS)
                return _curDoc;
        }
        return _curDoc;
    }

    abstract public int fetchDoc(int targetDoc) throws IOException;

    abstract public int fetchSec(int targetSec) throws IOException;

    protected int fetchPos() throws IOException {
        return NO_MORE_POSITIONS;
    }
}