Lucene example source code file (TermSpans.java)

This example Lucene source code file (TermSpans.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lucene tags/keywords

collection, end, io, ioexception, ioexception, override, override, spans, start, string, term, term, termpositions, termpositions, termspans, util

The Lucene TermSpans.java source code

package org.apache.lucene.search.spans;
/**
 * Copyright 2005 The Apache Software Foundation
 *
 * Licensed 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 org.apache.lucene.index.Term;
import org.apache.lucene.index.TermPositions;

import java.io.IOException;
import java.util.Collections;
import java.util.Collection;

/**
 * Expert:
 * Public for extension only
 */
public class TermSpans extends Spans {
  protected TermPositions positions;
  protected Term term;
  protected int doc;
  protected int freq;
  protected int count;
  protected int position;


  public TermSpans(TermPositions positions, Term term) throws IOException {

    this.positions = positions;
    this.term = term;
    doc = -1;
  }

  @Override
  public boolean next() throws IOException {
    if (count == freq) {
      if (!positions.next()) {
        doc = Integer.MAX_VALUE;
        return false;
      }
      doc = positions.doc();
      freq = positions.freq();
      count = 0;
    }
    position = positions.nextPosition();
    count++;
    return true;
  }

  @Override
  public boolean skipTo(int target) throws IOException {
    if (!positions.skipTo(target)) {
      doc = Integer.MAX_VALUE;
      return false;
    }

    doc = positions.doc();
    freq = positions.freq();
    count = 0;

    position = positions.nextPosition();
    count++;

    return true;
  }

  @Override
  public int doc() {
    return doc;
  }

  @Override
  public int start() {
    return position;
  }

  @Override
  public int end() {
    return position + 1;
  }

  // TODO: Remove warning after API has been finalized
  @Override
  public Collection<byte[]> getPayload() throws IOException {
    byte [] bytes = new byte[positions.getPayloadLength()]; 
    bytes = positions.getPayload(bytes, 0);
    return Collections.singletonList(bytes);
  }

  // TODO: Remove warning after API has been finalized
  @Override
  public boolean isPayloadAvailable() {
    return positions.isPayloadAvailable();
  }

  @Override
  public String toString() {
    return "spans(" + term.toString() + ")@" +
            (doc == -1 ? "START" : (doc == Integer.MAX_VALUE) ? "END" : doc + "-" + position);
  }


  public TermPositions getPositions() {
    return positions;
  }
}