com.google.gerrit.index.query.FieldBundle Maven / Gradle / Ivy
// Copyright (C) 2017 The Android Open Source Project
//
// 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.
package com.google.gerrit.index.query;
import static com.google.common.base.Preconditions.checkArgument;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableListMultimap;
import com.google.common.collect.Iterables;
import com.google.common.collect.ListMultimap;
import com.google.gerrit.index.IndexedField;
import com.google.gerrit.index.IndexedField.SearchSpec;
import com.google.gerrit.index.SchemaFieldDefs.SchemaField;
/** FieldBundle is an abstraction that allows retrieval of raw values from different sources. */
public class FieldBundle {
// Map String => List{Integer, Long, Timestamp, String, byte[]}
private ImmutableListMultimap fields;
/**
* Depending on the index implementation 1) either {@link IndexedField} are stored once and
* referenced by {@link com.google.gerrit.index.IndexedField.SearchSpec} on the queries, 2) or
* each {@link com.google.gerrit.index.IndexedField.SearchSpec} is stored individually.
*
* In case #1 {@link #storesIndexedFields} is set to {@code true} and the {@link #fields}
* contain a map from {@link IndexedField#name()} to a stored value.
*
*
In case #2 {@link #storesIndexedFields} is set to {@code false} and the {@link #fields}
* contain a map from {@link SearchSpec#name()} to a stored value.
*/
private final boolean storesIndexedFields;
public FieldBundle(ListMultimap fields, boolean storesIndexedFields) {
this.fields = ImmutableListMultimap.copyOf(fields);
this.storesIndexedFields = storesIndexedFields;
}
/**
* Get a field's value based on the field definition.
*
* @param schemaField the definition of the field of which the value should be retrieved. The
* field must be stored and contained in the result set as specified by {@link
* com.google.gerrit.index.QueryOptions}.
* @param Data type of the returned object based on the field definition
* @return Either a single element or an Iterable based on the field definition. An empty list is
* returned for repeated fields that are not contained in the result.
* @throws IllegalArgumentException if the requested field is not stored or not present. This
* check is only enforced on non-repeatable fields.
*/
@SuppressWarnings("unchecked")
public T getValue(SchemaField schemaField) {
checkArgument(schemaField.isStored(), "Field must be stored");
String storedFieldName =
storesIndexedFields && schemaField instanceof IndexedField.SearchSpec
? ((IndexedField.SearchSpec) schemaField).getField().name()
: schemaField.getName();
checkArgument(
fields.containsKey(storedFieldName) || schemaField.isRepeatable(),
"Field %s is not in result set %s",
storedFieldName,
fields.keySet());
ImmutableList