+++ /dev/null
-package org.apache.lucene.search.function;
-
-/**
- * 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 java.io.IOException;
-
-import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.search.FieldCache;
-
-/**
- * Expert: A base class for ValueSource implementations that retrieve values for
- * a single field from the {@link org.apache.lucene.search.FieldCache FieldCache}.
- * <p>
- * Fields used herein must be indexed (doesn't matter if these fields are stored or not).
- * <p>
- * It is assumed that each such indexed field is untokenized, or at least has a single token in a document.
- * For documents with multiple tokens of the same field, behavior is undefined (It is likely that current
- * code would use the value of one of these tokens, but this is not guaranteed).
- * <p>
- * Document with no tokens in this field are assigned the <code>Zero</code> value.
- *
- * @lucene.experimental
- *
- * <p><b>NOTE</b>: with the switch in 2.9 to segment-based
- * searching, if {@link #getValues} is invoked with a
- * composite (multi-segment) reader, this can easily cause
- * double RAM usage for the values in the FieldCache. It's
- * best to switch your application to pass only atomic
- * (single segment) readers to this API.</p>
- */
-public abstract class FieldCacheSource extends ValueSource {
- private String field;
-
- /**
- * Create a cached field source for the input field.
- */
- public FieldCacheSource(String field) {
- this.field=field;
- }
-
- /* (non-Javadoc) @see org.apache.lucene.search.function.ValueSource#getValues(org.apache.lucene.index.IndexReader) */
- @Override
- public final DocValues getValues(IndexReader reader) throws IOException {
- return getCachedFieldValues(FieldCache.DEFAULT, field, reader);
- }
-
- /* (non-Javadoc) @see org.apache.lucene.search.function.ValueSource#description() */
- @Override
- public String description() {
- return field;
- }
-
- /**
- * Return cached DocValues for input field and reader.
- * @param cache FieldCache so that values of a field are loaded once per reader (RAM allowing)
- * @param field Field for which values are required.
- * @see ValueSource
- */
- public abstract DocValues getCachedFieldValues(FieldCache cache, String field, IndexReader reader) throws IOException;
-
- /*(non-Javadoc) @see java.lang.Object#equals(java.lang.Object) */
- @Override
- public final boolean equals(Object o) {
- if (!(o instanceof FieldCacheSource)) {
- return false;
- }
- FieldCacheSource other = (FieldCacheSource) o;
- return
- this.field.equals(other.field) &&
- cachedFieldSourceEquals(other);
- }
-
- /*(non-Javadoc) @see java.lang.Object#hashCode() */
- @Override
- public final int hashCode() {
- return
- field.hashCode() +
- cachedFieldSourceHashCode();
- }
-
- /**
- * Check if equals to another {@link FieldCacheSource}, already knowing that cache and field are equal.
- * @see Object#equals(java.lang.Object)
- */
- public abstract boolean cachedFieldSourceEquals(FieldCacheSource other);
-
- /**
- * Return a hash code of a {@link FieldCacheSource}, without the hash-codes of the field
- * and the cache (those are taken care of elsewhere).
- * @see Object#hashCode()
- */
- public abstract int cachedFieldSourceHashCode();
-}
fnp / pylucene.git / blobdiff