/**
* 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.
*/
package org.apache.solr.search.function;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.*;
import org.apache.solr.search.function.DocValues;
import java.io.IOException;
import java.io.Serializable;
import java.util.IdentityHashMap;
import java.util.Map;
/**
* Instantiates {@link org.apache.solr.search.function.DocValues} for a particular reader.
* <br>
* Often used when creating a {@link FunctionQuery}.
*
* @version $Id: ValueSource.java 949467 2010-05-30 04:10:13Z hossman $
*/
public abstract class ValueSource implements Serializable {
@Deprecated
public DocValues getValues(IndexReader reader) throws IOException {
return getValues(null, reader);
}
/** Gets the values for this reader and the context that was previously
* passed to createWeight()
*/
public DocValues getValues(Map context, IndexReader reader) throws IOException {
return getValues(reader);
}
public abstract boolean equals(Object o);
public abstract int hashCode();
/** description of field, used in explain() */
public abstract String description();
public String toString() {
return description();
}
/** Implementations should propagate createWeight to sub-ValueSources which can optionally store
* weight info in the context. The context object will be passed to getValues()
* where this info can be retrieved. */
public void createWeight(Map context, Searcher searcher) throws IOException {
}
/** Returns a new non-threadsafe context map. */
public static Map newContext() {
return new IdentityHashMap();
}
}
class ValueSourceScorer extends Scorer {
protected IndexReader reader;
private int doc = -1;
protected final int maxDoc;
protected final DocValues values;
protected boolean checkDeletes;
protected ValueSourceScorer(IndexReader reader, DocValues values) {
super(null);
this.reader = reader;
this.maxDoc = reader.maxDoc();
this.values = values;
setCheckDeletes(true);
}
public IndexReader getReader() { return reader; }
public void setCheckDeletes(boolean checkDeletes) {
this.checkDeletes = checkDeletes && reader.hasDeletions();
}
public boolean matches(int doc) {
return (!checkDeletes || !reader.isDeleted(doc)) && matchesValue(doc);
}
public boolean matchesValue(int doc) {
return true;
}
@Override
public int docID() {
return doc;
}
@Override
public int nextDoc() throws IOException {
for(;;) {
doc++;
if (doc >= maxDoc) return doc=NO_MORE_DOCS;
if (matches(doc)) return doc;
}
}
@Override
public int advance(int target) throws IOException {
// also works fine when target==NO_MORE_DOCS
doc = target-1;
return nextDoc();
}
public int doc() {
return doc;
}
public boolean next() {
for(;;) {
doc++;
if (doc >= maxDoc) return false;
if (matches(doc)) return true;
}
}
public boolean skipTo(int target) {
doc = target-1;
return next();
}
public float score() throws IOException {
return values.floatVal(doc);
}
public Explanation explain(int doc) throws IOException {
return values.explain(doc);
}
}