Lucene example source code file (SpanNearPayloadCheckQuery.java)

This example Lucene source code file (SpanNearPayloadCheckQuery.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

acceptstatus, collection, collection, io, ioexception, object, override, override, spannearpayloadcheckquery, spannearpayloadcheckquery, spanpositioncheckquery, string, stringbuilder, stringbuilder, util

The Lucene SpanNearPayloadCheckQuery.java source code

package org.apache.lucene.search.spans;
/**
 * 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 org.apache.lucene.util.ToStringUtils;

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


/**
 * Only return those matches that have a specific payload at
 * the given position.
 * <p/>
 * 
 */
public class SpanNearPayloadCheckQuery extends SpanPositionCheckQuery {
  protected final Collection<byte[]> payloadToMatch;

  /**
   * @param match          The underlying {@link SpanQuery} to check
   * @param payloadToMatch The {@link java.util.Collection} of payloads to match
   */
  public SpanNearPayloadCheckQuery(SpanNearQuery match, Collection<byte[]> payloadToMatch) {
    super(match);
    this.payloadToMatch = payloadToMatch;
  }

  @Override
  protected AcceptStatus acceptPosition(Spans spans) throws IOException {
    boolean result = spans.isPayloadAvailable();
    if (result == true) {
      Collection<byte[]> candidate = spans.getPayload();
      if (candidate.size() == payloadToMatch.size()) {
        //TODO: check the byte arrays are the same
        //hmm, can't rely on order here
        int matches = 0;
        for (byte[] candBytes : candidate) {
          //Unfortunately, we can't rely on order, so we need to compare all
          for (byte[] payBytes : payloadToMatch) {
            if (Arrays.equals(candBytes, payBytes) == true) {
              matches++;
              break;
            }
          }
        }
        if (matches == payloadToMatch.size()){
          //we've verified all the bytes
          return AcceptStatus.YES;
        } else {
          return AcceptStatus.NO;
        }
      } else {
        return AcceptStatus.NO;
      }
    }
    return AcceptStatus.NO;
  }

  @Override
  public String toString(String field) {
    StringBuilder buffer = new StringBuilder();
    buffer.append("spanPayCheck(");
    buffer.append(match.toString(field));
    buffer.append(", payloadRef: ");
    for (byte[] bytes : payloadToMatch) {
      ToStringUtils.byteArray(buffer, bytes);
      buffer.append(';');
    }
    buffer.append(")");
    buffer.append(ToStringUtils.boost(getBoost()));
    return buffer.toString();
  }

  @Override
  public Object clone() {
    SpanNearPayloadCheckQuery result = new SpanNearPayloadCheckQuery((SpanNearQuery) match.clone(), payloadToMatch);
    result.setBoost(getBoost());
    return result;
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) return true;
    if (!(o instanceof SpanNearPayloadCheckQuery)) return false;

    SpanNearPayloadCheckQuery other = (SpanNearPayloadCheckQuery) o;
    return this.payloadToMatch.equals(other.payloadToMatch)
            && this.match.equals(other.match)
            && this.getBoost() == other.getBoost();
  }

  @Override
  public int hashCode() {
    int h = match.hashCode();
    h ^= (h << 8) | (h >>> 25);  // reversible
    //TODO: is this right?
    h ^= payloadToMatch.hashCode();
    h ^= Float.floatToRawIntBits(getBoost());
    return h;
  }
}