package org.apache.lucene.search;
/**
* Copyright 2004 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 java.io.IOException;
/** An abstract base class for search implementations.
* Implements some common utility methods.
*/
public abstract class Searcher implements Searchable {
/** Returns the documents matching <code>query</code>. */
public final Hits search(Query query) throws IOException {
return search(query, (Filter)null);
}
/** Returns the documents matching <code>query</code> and
<code>filter</code>. */
public Hits search(Query query, Filter filter) throws IOException {
return new Hits(this, query, filter);
}
/** Returns documents matching <code>query</code> sorted by
* <code>sort</code>.
*/
public Hits search(Query query, Sort sort)
throws IOException {
return new Hits(this, query, null, sort);
}
/** Returns documents matching <code>query</code> and <code>filter</code>,
* sorted by <code>sort</code>.
*/
public Hits search(Query query, Filter filter, Sort sort)
throws IOException {
return new Hits(this, query, filter, sort);
}
/** Lower-level search API.
*
* <p>{@link HitCollector#collect(int,float)} is called for every non-zero
* scoring document.
*
* <p>Applications should only use this if they need <i>all</i> of the
* matching documents. The high-level search API ({@link
* Searcher#search(Query)}) is usually more efficient, as it skips
* non-high-scoring hits.
* <p>Note: The <code>score</code> passed to this method is a raw score.
* In other words, the score will not necessarily be a float whose value is
* between 0 and 1.
*/
public void search(Query query, HitCollector results)
throws IOException {
search(query, (Filter)null, results);
}
/** The Similarity implementation used by this searcher. */
private Similarity similarity = Similarity.getDefault();
/** Expert: Set the Similarity implementation used by this Searcher.
*
* @see Similarity#setDefault(Similarity)
*/
public void setSimilarity(Similarity similarity) {
this.similarity = similarity;
}
/** Expert: Return the Similarity implementation used by this Searcher.
*
* <p>This defaults to the current value of {@link Similarity#getDefault()}.
*/
public Similarity getSimilarity() {
return this.similarity;
}
}
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