Lucene example source code file (RegexQuery.java)

This example Lucene source code file (RegexQuery.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

filteredtermenum, io, ioexception, multitermquery, override, override, regexcapabilities, regexcapabilities, regexquery, regexquery, regextermenum, string, stringbuilder, stringbuilder, term

The Lucene RegexQuery.java source code

package org.apache.lucene.search.regex;

/**
 * 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.search.MultiTermQuery;
import org.apache.lucene.search.FilteredTermEnum;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.util.ToStringUtils;

import java.io.IOException;

/** Implements the regular expression term search query.
 * The expressions supported depend on the regular expression implementation
 * used by way of the {@link RegexCapabilities} interface.
 *
 * @see RegexTermEnum
 */
public class RegexQuery extends MultiTermQuery implements RegexQueryCapable {
  private RegexCapabilities regexImpl = new JavaUtilRegexCapabilities();
  private Term term;

  /** Constructs a query for terms matching <code>term. */
  public RegexQuery(Term term) {
    this.term = term;
  }
  
  public Term getTerm() { return term; }

  /**
   * Defines which {@link RegexCapabilities} implementation is used by this instance.
   *
   * @param impl
   */
  public void setRegexImplementation(RegexCapabilities impl) {
    this.regexImpl = impl;
  }

  /**
   * @return The implementation used by this instance.
   */
  public RegexCapabilities getRegexImplementation() {
    return regexImpl;
  }

  @Override
  protected FilteredTermEnum getEnum(IndexReader reader) throws IOException {
    return new RegexTermEnum(reader, term, regexImpl);
  }

  @Override
  public String toString(String field) {
    StringBuilder buffer = new StringBuilder();
    if (!term.field().equals(field)) {
      buffer.append(term.field());
      buffer.append(":");
    }
    buffer.append(term.text());
    buffer.append(ToStringUtils.boost(getBoost()));
    return buffer.toString();
  }

  /* generated by IntelliJ IDEA */
  @Override
  public boolean equals(Object o) {
    if (this == o) return true;
    if (o == null || getClass() != o.getClass()) return false;
    if (!super.equals(o)) return false;

    final RegexQuery that = (RegexQuery) o;

    return regexImpl.equals(that.regexImpl);
  }

  /* generated by IntelliJ IDEA */
  @Override
  public int hashCode() {
    int result = super.hashCode();
    result = 29 * result + regexImpl.hashCode();
    return result;
  }
}